Re: Venting & Drying Brick Veneer Wall

[Guest guest]

No direct experience in this exact situation but consider

1. IR Gun to check temp/conductivity differences as a surrogate to how well the

wall is doing from in to out.

2. I have actually used thermocouples and RH/T meters inside walls to see how

they react. Another opportunity.

3. Model it with WUFI

a) as you suggest to try it using the city data nearest you

and with a bake out in that room

I would also model the current with and without scenarios to see what the

differences really are.

4. It appears that you need a temperature difference (dT) to drive the drying

process to the outside since you'll have a vapor barrier that is equivalent to a

boundary condition of no dVP. And I think you're right - slow.

My thoughts.

Tony

...........................................................................

" Tony " Havics, CHMM, CIH, PE

pH2, LLC

PO Box 34140

Indianapolis, IN 46234

cell

90% of Risk Management is knowing where to place the decimal point...any

consultant can give you the other 10%â„ 

This message is from pH2. This message and any attachments may contain legally

privileged or confidential information, and are intended only for the individual

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not be copied or distributed without this statement.

Venting & Drying Brick Veneer Wall

We operate an environmental, health & safety company in a textbook Mixed-Humid

region. We often get involved with local builders and IAQ issues. I recently

started an interesting project that I'm sure falls within some of you guys'

expertise. I think this situation provides an opportunity to add to the body of

knowledge, at least anecdotally.

We have client (an established homebuilder) who built a ~6000 sqft residence 18

months ago, putting unfaced insulation & plastic in the walls with the expected

consequences in this mixed-humid climate. For some reason prior to occupancy,

he removed a 6 foot linear section of plastic from a second floor bedroom wall

(west-facing gable end of the 2-story home) and replaced the drywall & unfaced

insulation without the plastic vapor barrier. The drywall in this section shows

marginally damp, which I believe is partially due to this section being the sole

water vapor inlet along this wall. I was able to show him the effects of

plastic in the wall by opening a 2X3 ft section in this non-plastic portion and

by also opening another 2X3 ft section approximately 10 feet away along the same

wall in the same room. Opening the plastic-treated walls shows wet studs about

1/4 inch deep, but little or no visible mold, yet. (By the way, the trigger for

our involvement was to investigate the " problem " in the non-plastic portion of

wall which caused mold growth on a large picture hanging on this portion. This

was due no doubt to the wall being able to dry to the inside at this one section

of wall. I had some convincing to do to show that the plastic-treated wall

sections were the real problem.)

Now the interesting part…The homeowner is willing to allow us to monitor the

residence over the next year for mold growth as we attempt to dry the walls.

Both inspection openings are located behind large furniture so the sections do

not have to be permanently repaired in between inspections. The plastic-treated

wall section was resealed with aluminum duct tape to restore non-permeable

conditions to that section and to allow future monitoring. The builder wants to

avoid removing the brick for obvious reasons. I have confirmed an approximate

3/4 inch space between the drain plane and the brick veneer. We have access to

the top of the brick veneer to vent the top. There is room to allow a powered

ventilation approach along the top, if warranted or feasible.

The builder will open as many weep holes as required along the bottom of the

brick veneer. The builder also understands the need for a tight air barrier

(SCS, at this point) treatment at the inside walls.

Question. Is there any study to show an existing brick wall being successfully

dried by a retrofitted venting solution? There are a lot of homes in this

situation here and an alternate to removing brick is obviously attractive, IF it

works AND IF the IAQ is monitored for mold growth following the principle of Do

No Harm. To short-circuit some thought, I am familiar with the Straube &

Burnett text, the Lstiburek, et. al. work, Canadian research on rain screens &

brick veneer, etc.

What do you think, folks? Any research or experience with keeping the plastic

in place and successfully drying? Documented work seems to show the importance

of strong flow behind the brick, with an unvented wall showing problems,

regardless of vapor barrier situation, but...<grin>

FAIR USE NOTICE:

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specifically authorized by the copyright owner. We are making such material

available in our efforts to advance understanding of environmental, political,

human rights, economic, democracy, scientific, and social justice issues, etc.

We believe this constitutes a 'fair use' of any such copyrighted material as

provided for in section 107 of the US Copyright Law. In accordance with Title 17

U.S.C. Section 107, the material on this site is distributed without profit to

those who have expressed a prior interest in receiving the included information

for research and educational purposes. For more information go to:

http://www.law.cornell.edu/uscode/17/107.shtml. If you wish to use copyrighted

material from this site for purposes of your own that go beyond 'fair use', you

must obtain permission from the copyright owner.

[Guest guest]

Bruce, temporally drying brick and the airspace behind it is generally

for naught if it is left to later ventilate with summer air with

dew-points of 70 degrees on a sunlit wall that absorbs moisture. Are you

retrofitting and leaving the drying in place?

A couple of questions for you:

What is the substrate on the exterior of the stud wall and how is it

sealed? Can you get a good look at the integrity of it through the Hole

cut in the drywall?

What type of air barrier and damp proofing were incorporated into the

exterior wall behind the brick?

What summer time temperatures and relative humidities are being held in

the home?

I ask about the temperature because generally to get the problem behind

the picture you need to have a picture flat against the wall with no

ventilation air gap at the top between the wall and the picture frame or

there is a room temperature approaching the summer time dew-point. We

see mold occur behind pictures in South Florida when homes are held

below 73 degrees and the picture has marginal air gap behind it.

Also, I ask about the temperature also because it is not unusual for us

to get a half dozen calls a year to large homes held at or below 70

degrees with obvious consequences to anything that acts as a vapor

barrier. If that's the case, you really have a (IMHO) Challenge before

you.

Ron

Venting & Drying Brick Veneer Wall

We operate an environmental, health & safety company in a textbook

Mixed-Humid region. We often get involved with local builders and IAQ

issues. I recently started an interesting project that I'm sure falls

within some of you guys' expertise. I think this situation provides an

opportunity to add to the body of knowledge, at least anecdotally.

We have client (an established homebuilder) who built a ~6000 sqft

residence 18 months ago, putting unfaced insulation & plastic in the

walls with the expected consequences in this mixed-humid climate. For

some reason prior to occupancy, he removed a 6 foot linear section of

plastic from a second floor bedroom wall (west-facing gable end of the

2-story home) and replaced the drywall & unfaced insulation without the

plastic vapor barrier. The drywall in this section shows marginally

damp, which I believe is partially due to this section being the sole

water vapor inlet along this wall. I was able to show him the effects

of plastic in the wall by opening a 2X3 ft section in this non-plastic

portion and by also opening another 2X3 ft section approximately 10 feet

away along the same wall in the same room. Opening the plastic-treated

walls shows wet studs about 1/4 inch deep, but little or no visible

mold, yet. (By the way, the trigger for our involvement was to

investigate the " problem " in the non-plastic portion of wall which

caused mold growth on a large picture hanging on this portion. This was

due no doubt to the wall being able to dry to the inside at this one

section of wall. I had some convincing to do to show that the

plastic-treated wall sections were the real problem.)

Now the interesting part...The homeowner is willing to allow us to

monitor the residence over the next year for mold growth as we attempt

to dry the walls. Both inspection openings are located behind large

furniture so the sections do not have to be permanently repaired in

between inspections. The plastic-treated wall section was resealed with

aluminum duct tape to restore non-permeable conditions to that section

and to allow future monitoring. The builder wants to avoid removing the

brick for obvious reasons. I have confirmed an approximate 3/4 inch

space between the drain plane and the brick veneer. We have access to

the top of the brick veneer to vent the top. There is room to allow a

powered ventilation approach along the top, if warranted or feasible.

The builder will open as many weep holes as required along the bottom of

the brick veneer. The builder also understands the need for a tight air

barrier (SCS, at this point) treatment at the inside walls.

Question. Is there any study to show an existing brick wall being

successfully dried by a retrofitted venting solution? There are a lot of

homes in this situation here and an alternate to removing brick is

obviously attractive, IF it works AND IF the IAQ is monitored for mold

growth following the principle of Do No Harm. To short-circuit some

thought, I am familiar with the Straube & Burnett text, the Lstiburek,

et. al. work, Canadian research on rain screens & brick veneer, etc.

What do you think, folks? Any research or experience with keeping the

plastic in place and successfully drying? Documented work seems to show

the importance of strong flow behind the brick, with an unvented wall

showing problems, regardless of vapor barrier situation, but...<grin>

FAIR USE NOTICE:

This site contains copyrighted material the use of which has not always

been specifically authorized by the copyright owner. We are making such

material available in our efforts to advance understanding of

environmental, political, human rights, economic, democracy, scientific,

and social justice issues, etc. We believe this constitutes a 'fair use'

of any such copyrighted material as provided for in section 107 of the

US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the

material on this site is distributed without profit to those who have

expressed a prior interest in receiving the included information for

research and educational purposes. For more information go to:

http://www.law.cornell.edu/uscode/17/107.shtml. If you wish to use

copyrighted material from this site for purposes of your own that go

beyond 'fair use', you must obtain permission from the copyright owner.

[Guest guest]

Tony,

My company just completed a brick drying project (3 to 4 layers of red clay brick and

mortar) that took the greater part of 2 months to complete. We used Aqua-Dry

system and tremendous amounts of pressure differentials along with core

drilling to complete the project of a 100-year-old commercial brick building that

was converted into million dollar condominiums that are

close to the ocean.

From:

iequality [mailto:iequality ] On Behalf Of Tony Havics

Sent: Wednesday, September 06,

2006 1:10 PM

To: iequality

Subject: RE: Venting

& Drying Brick Veneer Wall

No direct experience in this exact situation but consider

1. IR Gun to check temp/conductivity differences as a surrogate to how well the

wall is doing from in to out.

2. I have actually used thermocouples and RH/T meters inside walls to see how

they react. Another opportunity.

3. Model it with WUFI

a) as you suggest to try it using the city data nearest you

and with a bake out in that room

I would also model the current with and without scenarios to see what the

differences really are.

4. It appears that you need a temperature difference (dT) to drive the drying

process to the outside since you'll have a vapor barrier that is equivalent to

a boundary condition of no dVP. And I think you're right - slow.

My thoughts.

Tony

...........................................................................

" Tony " Havics, CHMM, CIH, PE

pH2, LLC

PO Box 34140

Indianapolis, IN 46234

cell

90% of Risk Management is knowing where to place the decimal point...any consultant

can give you the other 10%â„ 

This message is from pH2. This message and any attachments may contain legally

privileged or confidential information, and are intended only for the

individual or entity identified above as the addressee. If you are not the

addressee, or if this message has been addressed to you in error, you are not

authorized to read, copy, or distribute this message and any attachments, and

we ask that you please delete this message and attachments (including all

copies) and notify the sender by return e-mail or by phone at .

Delivery of this message and any attachments to any person other than the

intended recipient(s) is not intended in any way to waive confidentiality or a

privilege. All personal messages express views only of the sender, which are

not to be attributed to pH2 and may not be copied or distributed without this

statement.

Venting & Drying Brick Veneer Wall

We operate an environmental, health & safety company in a textbook

Mixed-Humid region. We often get involved with local builders and IAQ issues. I

recently started an interesting project that I'm sure falls within some of you

guys' expertise. I think this situation provides an opportunity to add to the

body of knowledge, at least anecdotally.

We have client (an established homebuilder) who built a ~6000 sqft residence 18

months ago, putting unfaced insulation & plastic in the walls with the

expected consequences in this mixed-humid climate. For some reason prior to

occupancy, he removed a 6 foot linear section of plastic from a second floor

bedroom wall (west-facing gable end of the 2-story home) and replaced the drywall

& unfaced insulation without the plastic vapor barrier. The drywall in this

section shows marginally damp, which I believe is partially due to this section

being the sole water vapor inlet along this wall. I was able to show him the

effects of plastic in the wall by opening a 2X3 ft section in this non-plastic

portion and by also opening another 2X3 ft section approximately 10 feet away

along the same wall in the same room. Opening the plastic-treated walls shows

wet studs about 1/4 inch deep, but little or no visible mold, yet. (By the way,

the trigger for our involvement was to investigate the " problem " in

the non-plastic portion of wall which caused mold growth on a large picture

hanging on this portion. This was due no doubt to the wall being able to dry to

the inside at this one section of wall. I had some convincing to do to show

that the plastic-treated wall sections were the real problem.)

Now the interesting part…The homeowner is willing to allow us to monitor the

residence over the next year for mold growth as we attempt to dry the walls.

Both inspection openings are located behind large furniture so the sections do

not have to be permanently repaired in between inspections. The plastic-treated

wall section was resealed with aluminum duct tape to restore non-permeable

conditions to that section and to allow future monitoring. The builder wants to

avoid removing the brick for obvious reasons. I have confirmed an approximate

3/4 inch space between the drain plane and the brick veneer. We have access to

the top of the brick veneer to vent the top. There is room to allow a powered

ventilation approach along the top, if warranted or feasible.

The builder will open as many weep holes as required along the bottom of the

brick veneer. The builder also understands the need for a tight air barrier

(SCS, at this point) treatment at the inside walls.

Question. Is there any study to show an existing brick wall being successfully

dried by a retrofitted venting solution? There are a lot of homes in this

situation here and an alternate to removing brick is obviously attractive, IF

it works AND IF the IAQ is monitored for mold growth following the principle of

Do No Harm. To short-circuit some thought, I am familiar with the Straube &

Burnett text, the Lstiburek, et. al. work, Canadian research on rain screens

& brick veneer, etc.

What do you think, folks? Any research or experience with keeping the plastic

in place and successfully drying? Documented work seems to show the importance

of strong flow behind the brick, with an unvented wall showing problems,

regardless of vapor barrier situation, but...<grin>

FAIR USE NOTICE:

This site contains copyrighted material the use of which has not always been

specifically authorized by the copyright owner. We are making such material

available in our efforts to advance understanding of environmental, political,

human rights, economic, democracy, scientific, and social justice issues, etc.

We believe this constitutes a 'fair use' of any such copyrighted material as

provided for in section 107 of the US Copyright Law. In accordance with Title

17 U.S.C. Section 107, the material on this site is distributed without profit

to those who have expressed a prior interest in receiving the included

information for research and educational purposes. For more information go to: http://www.law.cornell.edu/uscode/17/107.shtml.

If you wish to use copyrighted material from this site for purposes of your own

that go beyond 'fair use', you must obtain permission from the copyright owner.

[Guest guest]

HI folks,

Interesting case.  I have some thoughts:

·

What’s

the sheathing made of?

·

How big

is the air gap?

·

I like

Tony’s idea of placing some data loggers inside both sections.

·

Dataloggers located in lower brick

vents and top brick vents would allow calculating mass of moisture removed per

lb of air; you might be able to estimate flow rate of air behind wall using hot

wire, doing a fan pressurization test on brick cavity and monitoring delta P; assuming

flow coefficient and calculating flow from area of openings; using tracer gas

(maybe inject in openings and measure at outlets and integrate concentration

over time or at least simple tracer decay)

·

WUFI

doesn’t model vapor transport by air flow, if venting isn’t drying it might

model it pretty well.

·

Was the

picture making an accidental vapor barrier in the wrong spot?  Did it have a glass cover?  I’ve had cases like that where the wall has

no vapor barrier but there mold on the pictures beneath glass, on the gypsum behind

the pictures, mirrors, chalkboards, but the rest of the wall is fine.

·

As things

are actually wet we are talking about evaporation from a

porous wooden studs, so heating the interior gyp would help a lot but is

probably a hard sell.

Terry Brennan

From: iequality [mailto:iequality ] On Behalf Of Tony Havics

Sent: Wednesday, September 06,

2006 4:10 PM

To: iequality

Subject: RE: Venting

& Drying Brick Veneer Wall

No direct experience in this exact situation but consider

1. IR Gun to check temp/conductivity differences as a surrogate to how well the

wall is doing from in to out.

2. I have actually used thermocouples and RH/T meters inside walls to see how

they react. Another opportunity.

3. Model it with WUFI

a) as you suggest to try it using the city data nearest you

and with a bake out in that room

I would also model the current with and without scenarios to see what the

differences really are.

4. It appears that you need a temperature difference (dT) to drive the drying

process to the outside since you'll have a vapor barrier that is equivalent to

a boundary condition of no dVP. And I think you're right - slow.

My thoughts.

Tony

...........................................................................

" Tony " Havics, CHMM, CIH, PE

pH2, LLC

PO Box 34140

Indianapolis, IN 46234

cell

90% of Risk Management is knowing where to place the decimal point...any

consultant can give you the other 10%â„ 

This message is from pH2. This message and any attachments may contain legally

privileged or confidential information, and are intended only for the

individual or entity identified above as the addressee. If you are not the

addressee, or if this message has been addressed to you in error, you are not

authorized to read, copy, or distribute this message and any attachments, and

we ask that you please delete this message and attachments (including all

copies) and notify the sender by return e-mail or by phone at .

Delivery of this message and any attachments to any person other than the

intended recipient(s) is not intended in any way to waive confidentiality or a

privilege. All personal messages express views only of the sender, which are

not to be attributed to pH2 and may not be copied or distributed without this

statement.

Venting & Drying Brick Veneer Wall

We operate an environmental, health & safety company in a textbook

Mixed-Humid region. We often get involved with local builders and IAQ issues. I

recently started an interesting project that I'm sure falls within some of you

guys' expertise. I think this situation provides an opportunity to add to the

body of knowledge, at least anecdotally.

We have client (an established homebuilder) who built a ~6000 sqft residence 18

months ago, putting unfaced insulation & plastic in the walls with the

expected consequences in this mixed-humid climate. For some reason prior to

occupancy, he removed a 6 foot linear section of plastic from a second floor

bedroom wall (west-facing gable end of the 2-story home) and replaced the

drywall & unfaced insulation without the plastic vapor barrier. The drywall

in this section shows marginally damp, which I believe is partially due to this

section being the sole water vapor inlet along this wall. I was able to show

him the effects of plastic in the wall by opening a 2X3 ft section in this

non-plastic portion and by also opening another 2X3 ft section approximately 10

feet away along the same wall in the same room. Opening the plastic-treated

walls shows wet studs about 1/4 inch deep, but little or no visible mold, yet.

(By the way, the trigger for our involvement was to investigate the

" problem " in the non-plastic portion of wall which caused mold growth

on a large picture hanging on this portion. This was due no doubt to the wall

being able to dry to the inside at this one section of wall. I had some

convincing to do to show that the plastic-treated wall sections were the real

problem.)

Now the interesting part…The homeowner is willing to allow us to monitor the

residence over the next year for mold growth as we attempt to dry the walls.

Both inspection openings are located behind large furniture so the sections do

not have to be permanently repaired in between inspections. The plastic-treated

wall section was resealed with aluminum duct tape to restore non-permeable

conditions to that section and to allow future monitoring. The builder wants to

avoid removing the brick for obvious reasons. I have confirmed an approximate

3/4 inch space between the drain plane and the brick veneer. We have access to

the top of the brick veneer to vent the top. There is room to allow a powered

ventilation approach along the top, if warranted or feasible.

The builder will open as many weep holes as required along the bottom of the

brick veneer. The builder also understands the need for a tight air barrier

(SCS, at this point) treatment at the inside walls.

Question. Is there any study to show an existing brick wall being successfully

dried by a retrofitted venting solution? There are a lot of homes in this

situation here and an alternate to removing brick is obviously attractive, IF

it works AND IF the IAQ is monitored for mold growth following the principle of

Do No Harm. To short-circuit some thought, I am familiar with the Straube &

Burnett text, the Lstiburek, et. al. work, Canadian research on rain screens

& brick veneer, etc.

What do you think, folks? Any research or experience with keeping the plastic

in place and successfully drying? Documented work seems to show the importance

of strong flow behind the brick, with an unvented wall showing problems,

regardless of vapor barrier situation, but...<grin>

FAIR USE NOTICE:

This site contains copyrighted material the use of which has not always been

specifically authorized by the copyright owner. We are making such material

available in our efforts to advance understanding of environmental, political,

human rights, economic, democracy, scientific, and social justice issues, etc.

We believe this constitutes a 'fair use' of any such copyrighted material as

provided for in section 107 of the US Copyright Law. In accordance with Title

17 U.S.C. Section 107, the material on this site is distributed without profit

to those who have expressed a prior interest in receiving the included

information for research and educational purposes. For more information go to: http://www.law.cornell.edu/uscode/17/107.shtml.

If you wish to use copyrighted material from this site for purposes of your own

that go beyond 'fair use', you must obtain permission from the copyright owner.

[Guest guest]

For some reason prior to occupancy, he removed a 6 foot linear section of

plastic from a second floor bedroom wall (west-facing gable end of the

2-story home) and replaced the drywall & unfaced insulation without the

plastic vapor barrier. The drywall in this section shows marginally

damp, which I believe is partially due to this section being the sole

water vapor inlet along this wall.

It may be the pathway by which vapor is drawn in from the wall cavity as you suspect, but I would want to know the reason the sheetrock and insulation were removed in the first place. If there was prior water damage in this area, the cause may be something more direct and local (i.e., water entering at the roof rake).

I would also try to assess the common problem of capillary bridging caused by mortar falling into the air space and contacting both the facade and the air barrier, which can wick moisture into the sheathing. Tyvek is porous and felt tar paper will eventually become microbially digested if constantly wet. IR thermography might be the best tool to find the wet spots -- especially after a good rain when the heat is on to intensify evaporative cooling.

Power venting of a wall system does not seem cost-justifiable or feasible over the life of a building. Maybe just adding more weep holes will improve passive/convective ventilation. Applying and maintaining a silicone treatment to the exterior might also be a somewhat effective band-aid.

Just some thoughts. I'm involved in a couple of situations involving brick exteriors now.

Steve Temes

[Guest guest]

,

I am involved in a 100-year-old brick wall residential rehab now.

I'm curious to know about finished wall construction details in the brick building you dried. Were wall framing members fastened to the exterior brick or was an air space left? The developers altered the architect's original plans and left two inches behind all the exterior finished walls on my recommendation two years ago when I inspected the buildings in the post-interior demolition phase and saw the potential for a big problem.

I am concerned about how they installed the windows in the holes in the brick walls. There is 2x6 pressure-treated lumber on the inside edge of the brick opening that the vinyl and metal windows fasten to. The window trim is entirely reliant on caulk to keep water out (no flashing/drainage plane). The brick will soak in water and wet the pressure-treated wood even if the caulking is well maintained.

Comments from anyone?

Steve Temes

My company just completed a brick drying project (3 to 4 layers of red clay brick and mortar) that took the greater part of 2 months to complete. We used Aqua-Dry system and tremendous amounts of pressure differentials along with core drilling to complete the project of a 100-year-old commercial brick building that was converted into million dollar condominiums that are close to the ocean.

[Guest guest]

Hi Bruce

Allow me to suggest a site that offers builders' guides for mixed climates. Few builders understand permeable vapor retarders or simply put "vapor migration" and the consequences of a vapor barrier placed in a structure.

www.eeba.org http://www.eeba.org/bookstore/book.asp?BookID=1

Valin

[Guest guest]

You might try (model first) Seal Krete on the exterior brick. It can repel via surface tension the water droplets and has a perm rating ca. 5 [Yes the manufacturer actually has perm data but I don't have the file handy] which also a reasonable amount of vapor through.

Seal Krete® (mod permability)

(Seal-Krete, , www.seal-krete.com)

But I think I would like to add some flashing. I might also look at the base and a place skrete layer below the brick to minimize capillary action from the bottom.

Also, I know of a couple contractors that have used:

Dry-Lock® Masonry Waterproofer

(United Gilsonite Laboratories, , www.ugl.com)

............................................................................ "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of AirwaysEnv@...Sent: Thursday, September 07, 2006 12:43 PMTo: iequality Subject: Re: Venting & Drying Brick Veneer Wall,I am involved in a 100-year-old brick wall residential rehab now.I'm curious to know about finished wall construction details in the brick building you dried. Were wall framing members fastened to the exterior brick or was an air space left? The developers altered the architect's original plans and left two inches behind all the exterior finished walls on my recommendation two years ago when I inspected the buildings in the post-interior demolition phase and saw the potential for a big problem.I am concerned about how they installed the windows in the holes in the brick walls. There is 2x6 pressure-treated lumber on the inside edge of the brick opening that the vinyl and metal windows fasten to. The window trim is entirely reliant on caulk to keep water out (no flashing/drainage plane). The brick will soak in water and wet the pressure-treated wood even if the caulking is well maintained.Comments from anyone?Steve Temes

My company just completed a brick drying project (3 to 4 layers of red clay brick and mortar) that took the greater part of 2 months to complete. We used Aqua-Dry system and tremendous amounts of pressure differentials along with core drilling to complete the project of a 100-year-old commercial brick building that was converted into million dollar condominiums that are close to the ocean.

[Guest guest]

My experience with brick is that the expansion and contraction of the brick yearly would be such that any sealer unless it has any bridging and tear resistance will need yearly application and maintenance. Additionally the mortar is sacrificial, so that over time the mortar will erode away and the brick requires retuck pointing. My brother-in-law (and yes I have some in-law stories) sealed his brick and retucked the first few rows from grade with high strength grout on his 70 year old home. After the face started shearing off the brick he called to ask if I knew why! Well one of two things happened, one the brick got moist and the cold weather caused the water retained at the face of the block to freeze breaking it off or the brick couldn't expand against the high strength grout and the face sheared. Our guess since it was the layers that were retucked and the lower layers at grade were affected was that it had to do with the expansion, so he chipped out the grout and went back with standard mortar. Our other guess was that the lower brick was wicking water from the ground and the sealer allowed moisture buildup to cause the shearing problem when it froze, so we had him steel wool the face of the brick up to about 3 feet, he hasn't had any reoccurrences. Regardless check local practice on sealers before using them if there is a chance of freeze conditions and moisture retention in the brick, as I recall this project is in a mixed climate if it is far enough south freezing may not be an issue. BTW my brother-in-law is available for repointing brick, he's quite good at it now! Ron From: iequality [mailto:iequality ] On Behalf Of Tony HavicsSent: Thursday, September 07, 2006 6:05 PMTo: iequality Subject: RE: Venting & Drying Brick Veneer WallYou might try (model first) Seal Krete on the exterior brick. It can repel via surface tension the water droplets and has a perm rating ca. 5 [Yes the manufacturer actually has perm data but I don't have the file handy] which also a reasonable amount of vapor through. Seal Krete® (mod permability)(Seal-Krete, , www.seal-krete.com) But I think I would like to add some flashing. I might also look at the base and a place skrete layer below the brick to minimize capillary action from the bottom. Also, I know of a couple contractors that have used: Dry-Lock® Masonry Waterproofer(United Gilsonite Laboratories, , www.ugl.com) ........................................................................... "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%℠This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of AirwaysEnv@...Sent: Thursday, September 07, 2006 12:43 PMTo: iequality Subject: Re: Venting & Drying Brick Veneer Wall,I am involved in a 100-year-old brick wall residential rehab now.I'm curious to know about finished wall construction details in the brick building you dried. Were wall framing members fastened to the exterior brick or was an air space left? The developers altered the architect's original plans and left two inches behind all the exterior finished walls on my recommendation two years ago when I inspected the buildings in the post-interior demolition phase and saw the potential for a big problem.I am concerned about how they installed the windows in the holes in the brick walls. There is 2x6 pressure-treated lumber on the inside edge of the brick opening that the vinyl and metal windows fasten to. The window trim is entirely reliant on caulk to keep water out (no flashing/drainage plane). The brick will soak in water and wet the pressure-treated wood even if the caulking is well maintained.Comments from anyone?Steve Temes My company just completed a brick drying project (3 to 4 layers of red clay brick and mortar) that took the greater part of 2 months to complete. We used Aqua-Dry system and tremendous amounts of pressure differentials along with core drilling to complete the project of a 100-year-old commercial brick building that was converted into million dollar condominiums that are close to the ocean.

[Guest guest]

Steve,

To set the Stage:

1. The building was a two-story warehouse that has

since been converted into million dollar two story with loft condo’s

about 4 blocks from the ocean.

2. The remodeling contractor applied plaster and paint to the interior

walls of clay brick, only to find out that several months later blistering and

cracking occurred in the interior finishes.

3. Further examination reported the brick is porous from outside as

well as roof related problems.

4. The contractor fixed the roof and placed an elastomeric coating over

the outside stucco, thinking this would take care of the problem. Then, he

installed Sears’s quality dehumidifiers indoors, hoping they will capture

the remainder of excess moisture.

5. The blistering continued including signs of interior plaster

efflorescence.

6. A water damage restoration contractor was then

hired to dry the interior. They used a combination of refrigerant and desiccant

dehumidifiers over a period of weeks. The results of moisture content change in

plaster, brick and mortar did not provide a dramatic change on values.

7. My company installed dataloggers outside and inside the building and

we cored in the walls to install other dataloggers. The results of the

preliminary moisture test data reported trapped moisture in walls that became

worse during evening fog, high humidity and rainy days.

8. The result of meetings with engineers confirmed, the building had

major water intrusion sources and the plaster finish and paint problem was not

going away. The intention was to remove the quarter inch up to half inch thick plaster to allow the brick to breathe from

inside the building, since the outside can no longer breathe because of the

elastomeric coating on stucco.

Our Goal:

1.

First, to recognize our liability and exposure to a potential

future lawsuit: In an attempt to limit that exposure, we wrote a “structural

drying scope of work” that we would follow what we believed was

reasonable based on best known information, and the recommendations of their

engineer and at some point in time was to determine when the building brick and

mortar was dry to a moisture point they were satisfied with our work. In this case, we separated our self from being the independent

environmental and drying specialist, since we were now actively involved with

the drying phase.

2.

We set

up a test area that could be secured. We modeled the

drying process with 2,000 cfm of heated air pressure from outdoors. We

determined the best indoor heat and temperature at the red clay brick surfaces was

130F (+/- 10F). The test area surface was close to immediate drying, but the

core (2-layers of red clay brick deep) did not change over a 24-36 hours. (The age

of the mortar like the brick is 100 years old, and the mortar and pointing in

some areas was disintegrating back to sand. A closer examination by removing 8 foot long x 5 foot high first and second layers of loose

brick showed major repair of the structure is required.) We found that core

drilling and pressurizing the interior core worked best. In our case we had to drive the moisture out through massive cross-air

ventilation, since we could not just pressurize the walls since they had an

elastomeric coating on them.

3.

Success where

their engineer determined dryness for each condo took two-three weeks each.

From: iequality [mailto:iequality ] On Behalf Of AirwaysEnv@...

Sent: Thursday, September 07, 2006

10:43 AM

To: iequality

Subject: Re: Venting

& Drying Brick Veneer Wall

,

I am involved in a 100-year-old brick wall residential rehab now.

I'm curious to know about finished wall construction details in the brick

building you dried. Were wall framing members fastened to the exterior

brick or was an air space left? The developers altered the architect's

original plans and left two inches behind all the exterior finished walls on my

recommendation two years ago when I inspected the buildings in the

post-interior demolition phase and saw the potential for a big problem.

I am concerned about how they installed the windows in the holes in the brick

walls. There is 2x6 pressure-treated lumber on the inside edge of the

brick opening that the vinyl and metal windows fasten to. The window trim

is entirely reliant on caulk to keep water out (no flashing/drainage

plane). The brick will soak in water and wet the pressure-treated wood

even if the caulking is well maintained.

Comments from anyone?

Steve Temes

In a message dated 9/7/2006 11:15:37 AM Eastern Standard Time, pmoffettemeiaq

writes:

My company just completed

a brick drying project (3 to 4 layers of red clay brick and mortar) that took

the greater part of 2 months to complete. We used Aqua-Dry system and

tremendous amounts of pressure differentials along with core drilling to

complete the project of a 100-year-old commercial brick building that was

converted into million dollar condominiums that are close to the ocean.

[Guest guest]

One other thought, did you check the home to assure negative pressure

doesn't develop with the doors of different areas closed?

Terry, remember that residence in Hallandale, Florida you and I were on,

where the picture was stuck to the wall? There was so much mold behind

it, it was holding it to the wall.

It was the model for the full employment act for consultants, no air

space between the wall and the picture, Glass front, negative pressure

and 68 degrees indoors in the middle of summer.

[Guest guest]

Steve:

You ask a mighty good question, and are very astute. Yes, on many masonry buildings, standard practice was/is to let-in a PT 2x4 or 2x6, from which the window frame could be attached. Then, the entire assembly would be sealed to the masonry units, at the edges, with caulking. This was standard practice in the 70s, 80, and early 90s when I was more involved with construction, and I believe it continues to this day.

You describe a condition in a wall assembly that I feel represents a weak link in some locations, i.e., the wood let-in in a masonry wall assembly. This said, because the masonry wall assembly is a massive wall system and the mass, in theory, will attenuate the migration of water that could/would affect the sealer and/or the wood member (which expands when moist) let-in in a masonry wall assembly (which does not expand when moist), the rate of moisture migration and its effects are ASSUMED to be negligible. Moreover, masonry wall assemblies do well when there are extended periods of drying (or drying potential) between periods of moisture. This said, if this wall/window assembly was in the Pacific Northwest where there is very little drying potential, I foresee a really big problem, when in 5 to 10 years the windows start falling out. I believe that untreated masonry wall systems just don’t do well in areas with continuous moisture. On the other hand, masonry wall systems with the wood let-in and are located in drier climates, seem to do very well with this type of window attachment. On some demolitions projects I have been at, with 40-yr old buildings, and with this type of window attachment/assembly, they showed no signs of rot and few signs of leakage – attesting to their performance.

Yes....There are other methods of attachment that do not use wood let-ins, and do not over-rely on sealants. But these come with a substantially higher unit cost. Given a big building with a lot of windows, the wood let-in represents a significant cost savings.....in the construction!

For what it is worth....

--

Geyer, PE, CIH, CSP

President

KERNTEC Industries, Inc.

Bakersfield, California

www.kerntecindustries.com

,

I am involved in a 100-year-old brick wall residential rehab now.

I'm curious to know about finished wall construction details in the brick building you dried. Were wall framing members fastened to the exterior brick or was an air space left? The developers altered the architect's original plans and left two inches behind all the exterior finished walls on my recommendation two years ago when I inspected the buildings in the post-interior demolition phase and saw the potential for a big problem.

I am concerned about how they installed the windows in the holes in the brick walls. There is 2x6 pressure-treated lumber on the inside edge of the brick opening that the vinyl and metal windows fasten to. The window trim is entirely reliant on caulk to keep water out (no flashing/drainage plane). The brick will soak in water and wet the pressure-treated wood even if the caulking is well maintained.

Comments from anyone?

Steve Temes

My company just completed a brick drying project (3 to 4 layers of red clay brick and mortar) that took the greater part of 2 months to complete. We used Aqua-Dry system and tremendous amounts of pressure differentials along with core drilling to complete the project of a 100-year-old commercial brick building that was converted into million dollar condominiums that are close to the ocean.

[Guest guest]

sealed his brick and retucked the first few rows from grade with high strength grout on his 70 year old home. After the face started shearing off the brick he called to ask if I knew why! Well one of two things happened, one the brick got moist and the cold weather caused the water retained at the face of the block to freeze breaking it off or the brick couldn't expand against the high strength grout and the face sheared.

Thanks for that story, Ron. Good stuff. I knew the below had to do with water, but I didn't attribute the phenomenon to the strength of the mortar......

Steve Temes

[Guest guest]

You describe a condition in a wall assembly that I feel represents a weak link in some locations, i.e., the wood let-in in a masonry wall assembly. This said, because the masonry wall assembly is a massive wall system and the mass, in theory, will attenuate the migration of water that could/would affect the sealer and/or the wood member (which expands when moist) let-in in a masonry wall assembly (which does not expand when moist), the rate of moisture migration and its effects are ASSUMED to be negligible.

A little bit of sill gasket might go a long way here. It's too late for the windows in my project, though. Unfortunately, reviewing architectrual drawings and overseeing construction was way outside of my scope of work. Heck, recommending that they don't nail wood wall framing to the inside of the brick was technically outside of my scope. The architect realized I was right and changed the floor plans to leave the 2" air space behind the walls as the model was being built. Regular inspection is what I have to recommend now.

Steve Temes

[Guest guest]

We could overlay pictures except my cleaver

brother-in law used a clear sealer of some type, but that is exactly what

started happening, he noticed his in the early spring, after a very cold winter.

They live in upstate New York

near the Canadian US border.

Ron

From: iequality [mailto:iequality ] On Behalf Of AirwaysEnv@...

Sent: Friday, September 08, 2006

11:57 PM

To: iequality

Subject: Re: Venting

& Drying Brick Veneer Wall

In a message dated

9/8/2006 10:52:11 AM Eastern Standard Time, ron@... writes:

sealed his brick and

retucked the first few rows from grade with high strength grout on his 70 year

old home. After the face started shearing off the brick he called to ask if I

knew why! Well one of two things happened, one the brick got moist and the cold

weather caused the water retained at the face of the block to freeze breaking

it off or the brick couldn't expand against the high strength grout and the

face sheared.

Thanks for that story, Ron. Good stuff. I knew

the below had to do with water, but I didn't attribute the phenomenon to the

strength of the mortar......

Steve Temes

[Guest guest]

We have lots of problems with brick and

concrete spalling in the UK which is often caused by

the adsorption of salt from de-icing procedures following snow or ice. The salt

water splashed up the wall where it evaporates and leaves the salt to

re-crystallize. Pressures up to a couple of tons per square inch are said to

result although I have no data. One point regarding re pointing, different

types, (styles)

of pointing are used, but the most important factor especially

with old masonry is the use of “Hydraulic Lime putty or mortar. This is

weaker than Portland cement and allows movement etc.

Where salt or corrosion is a problem,

(re-bars) (brick ties) (spalling) I apply a breathable impregnation

“Siloxane” as a moisture barrier, usually invisible it allows the

substrate to breathe through vapor pressure but prevents adsorption. Never

apply a moisture barrier paint etc above the damp course.

Regards

Jeff Charlton

London

[Guest guest]

I am going to refer to the comment that included pictures of

spalling brick. I just completed an inspection on a brick building

that was over 100 years old. This building had a pattern of spalled

brick from the roof down the side, obviously where water had been running

down the side of the building for some reason. The picture is shown

below. Notice that not all of the brick popped. I am not sure

why; but apparently it has to do with the various brick

characteristics.

This problem is due to water being absorbed by the brick, freezing and

then popping the surface material off. The thing is the problem

occurred only in areas where the brick really absorbed a lot of

water--not brick exposed to normal rains and humidity conditions.

Maybe something else is at play here.

I noted Ron's story about his brother-in-law using grout for

mortar. You have to be really cautious about older buildings that

use " soft brick " and lime mortar. The soft brick is

pretty common in the older buildings around here. It is brick that

is not fired at higher temperatures like current brick. The mortar

is also different than current mortars. Any kind of work on this

type of mortar and brick has to be done with caution because the brick

and mortar can be easily damaged. For example, a power-washing

using pressures that are normal for current brick will cut soft brick and

lime mortar like a knife. For sure, the soft brick cannot be

replaced with current brick and current mortars cannot be used with soft

brick. Whenever I encounter these kinds of problems, I refer

clients to experts who work with old buildings because they need

TLC.

[Guest guest]

This problem is due to water being absorbed by the brick, freezing and then popping the surface material off. The thing is the problem occurred only in areas where the brick really absorbed a lot of water--not brick exposed to normal rains and humidity conditions. Maybe something else is at play here.

Looks like either a problem with the rain gutter or the chimney, which did not appear to have a cap.

Steve Temes

[Guest guest]

I see a stack at the top - was there a continuous fireplace flue up the middle portion of the building where the brick spalling is located? If so, see my last note on my fireplace and brick spalling.

I should say there are differences in bricks and batches. The old refereces I have on brick making and the materials info (going back to about the 1910s) suggest there were a lot of batch differences.

As for lime mortar - see:

Sickles-Taves, B. and Sheehan: Specifying Historic Materials: The Use of Lime. in in ASTM: STP 1432, Masonry, Opportunities for the 21st Century. D. Throop and RE Klinger, Eds. ASTM, Philadelphia, PA. 2002. pp. 3-22.

Also see attached pic on mortar joint style and long term collection of water (does not include styles: vee, flush, extruded, and beaded).

Tony

........................................................................... "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of Matt KleinSent: Monday, September 11, 2006 9:01 AMTo: iequality Subject: Re: Venting & Drying Brick Veneer WallI am going to refer to the comment that included pictures of spalling brick. I just completed an inspection on a brick building that was over 100 years old. This building had a pattern of spalled brick from the roof down the side, obviously where water had been running down the side of the building for some reason. The picture is shown below. Notice that not all of the brick popped. I am not sure why; but apparently it has to do with the various brick characteristics. This problem is due to water being absorbed by the brick, freezing and then popping the surface material off. The thing is the problem occurred only in areas where the brick really absorbed a lot of water--not brick exposed to normal rains and humidity conditions. Maybe something else is at play here.I noted Ron's story about his brother-in-law using grout for mortar. You have to be really cautious about older buildings that use "soft brick" and lime mortar. The soft brick is pretty common in the older buildings around here. It is brick that is not fired at higher temperatures like current brick. The mortar is also different than current mortars. Any kind of work on this type of mortar and brick has to be done with caution because the brick and mortar can be easily damaged. For example, a power-washing using pressures that are normal for current brick will cut soft brick and lime mortar like a knife. For sure, the soft brick cannot be replaced with current brick and current mortars cannot be used with soft brick. Whenever I encounter these kinds of problems, I refer clients to experts who work with old buildings because they need TLC.

[Guest guest]

I see a stack at the top - was there a

continuous fireplace flue up the middle portion of the building where the

brick spalling is located? If so, see my last note on my fireplace

and brick spalling.

The picture may not show it very well; but there is a chimney very near

the outside wall where the spalling occurred. What appears to have

happened is that a former roof channel water over the edge of the

building and down the wall, rather than channeling it back onto the roof

so that it could flow to a gutter at the end of the roof. You can

still see some of the damage the water did to the trim board under the

roof edge. This building had nearly a flat roof that slanted

slightly downward from left to right in the photo. Some of the

water coming down the roof could go over the edge of the roof if a baffle

or other device did not channel it back onto the roof. A few years ago,

the metal or roll roofing that used to be the roofing was replaced with a

membrane roof. That appears to have stopped the rain water from

flowing over the side of the roof. I hope that clarifies a couple

of things.

************************************************************

K. Klein, PE ME, MBA

Indoor Air Quality Solutions, Inc.

2523 SR 133

Bethel, OH 45106-0007

VOICE:

FAX: (with notice)

E-mail: mkklein68@...

************************************************************

Wouldn't it be nice if common sense were really common?

[Guest guest]

Jeff:

Your use of a siloxane-based sealer is a great method, and it is one of the best methods to reduce water absorptivity while not substantially changing porosity of the clay body. However, from an IAQ perspective, I am finding a lot of siloxanes in indoor air samples. Something that was not present 15-years ago. Still unsure what it all means.

For what it is worth....

--

Geyer, PE, CIH, CSP

President

KERNTEC Industries, Inc.

Bakersfield, California

www.kerntecindustries.com

We have lots of problems with brick and concrete spalling in the UK which is often caused by the adsorption of salt from de-icing procedures following snow or ice. The salt water splashed up the wall where it evaporates and leaves the salt to re-crystallize. Pressures up to a couple of tons per square inch are said to result although I have no data. One point regarding re pointing, different types, (styles) of pointing are used, but the most important factor especially with old masonry is the use of “Hydraulic Lime putty or mortar. This is weaker than Portland cement and allows movement etc.

Where salt or corrosion is a problem, (re-bars) (brick ties) (spalling) I apply a breathable impregnation “Siloxane” as a moisture barrier, usually invisible it allows the substrate to breathe through vapor pressure but prevents adsorption. Never apply a moisture barrier paint etc above the damp course.

Regards

Jeff Charlton

London

[Guest guest]

Thanks

,

Yes

all applications should be outside but the main problem from spalling is |I

have found to be is frost damage and | doubt if some of the areas discussed

have much of that! Indoors I would utilise hydrolysed lithium quartz, suspect

that it may too have problems but it may be a trade off between mould or chemical

hazards,

Regards

Jeff Charlton

London

-----Original

Message-----

From: iequality

[mailto:iequality ] On Behalf

Of Geyer

Sent: 12 September 2006 00:48

To: iequality

Subject: Re: Venting

& Drying Brick Veneer Wall

Jeff:

Your use of a siloxane-based sealer is a great method, and it is one of the

best methods to reduce water absorptivity while not substantially changing

porosity of the clay body. However, from an IAQ perspective, I am finding

a lot of siloxanes in indoor air samples. Something that was not present

15-years ago. Still unsure what it all means.

For what it is worth....

--

Geyer, PE, CIH, CSP

President

KERNTEC Industries, Inc.

Bakersfield, California

www.kerntecindustries.com

On 9/10/06 1:38 AM, " J Charlton " <j-charltonbtclick>

wrote:

We have lots of problems

with brick and concrete spalling in the UK which is often caused by the

adsorption of salt from de-icing procedures following snow or ice. The salt

water splashed up the wall where it evaporates and leaves the salt to

re-crystallize. Pressures up to a couple of tons per square inch are said to

result although I have no data. One point regarding re pointing, different

types, (styles) of pointing are used, but the most important factor especially

with old masonry is the use of “Hydraulic Lime putty or mortar. This is

weaker than Portland cement and allows movement etc.

Where salt or corrosion is a problem, (re-bars) (brick ties) (spalling) I

apply a breathable impregnation “Siloxane” as a moisture barrier,

usually invisible it allows the substrate to breathe through vapor pressure but

prevents adsorption. Never apply a moisture barrier paint etc above the damp

course.

Regards

Jeff Charlton

London

[Guest guest]

(Apologies for thoise that don't like attachments)

Interesting on the siloxane. What did you use for the method and what levels are you finding?

- see attached head pressure test (standpipe held on with plumber's putty) on a siloxane based coating on a commecial brick building. Note that both tests are on the mortar which is the weakest point. Manufacturer warranties the coating for 15 years. I did the capital equivalent calcs for 21 years based on re-coating and tuckpointing every 7 years (don't trust the manufacturer's data). It was better to coat than replace. We figured with minor cracks and the like that 7 years for the brickwork as well.

Tony

........................................................................... "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of GeyerSent: Monday, September 11, 2006 6:48 PMTo: iequality Subject: Re: Venting & Drying Brick Veneer WallJeff:Your use of a siloxane-based sealer is a great method, and it is one of the best methods to reduce water absorptivity while not substantially changing porosity of the clay body. However, from an IAQ perspective, I am finding a lot of siloxanes in indoor air samples. Something that was not present 15-years ago. Still unsure what it all means.For what it is worth....-- Geyer, PE, CIH, CSPPresidentKERNTEC Industries, Inc.Bakersfield, Californiawww.kerntecindustries.com

We have lots of problems with brick and concrete spalling in the UK which is often caused by the adsorption of salt from de-icing procedures following snow or ice. The salt water splashed up the wall where it evaporates and leaves the salt to re-crystallize. Pressures up to a couple of tons per square inch are said to result although I have no data. One point regarding re pointing, different types, (styles) of pointing are used, but the most important factor especially with old masonry is the use of “Hydraulic Lime putty or mortar. This is weaker than Portland cement and allows movement etc.Where salt or corrosion is a problem, (re-bars) (brick ties) (spalling) I apply a breathable impregnation “Siloxane†as a moisture barrier, usually invisible it allows the substrate to breathe through vapor pressure but prevents adsorption. Never apply a moisture barrier paint etc above the damp course.RegardsJeff CharltonLondon

[Guest guest]

Tony:

I am duly impressed. And to think you are putting water pressure right on the mortar joint, which I always consider a pathway. Wow! The siloxane coating appears to be working remarkable well from your photos. Thanks for sharing the photo.

Regarding siloxanes in the air....We (my chemist buddy, who is a real gem) found siloxanes when conducting several IAQ investigations that were complaint driven. Like many IAQ investigations, the client says “Find something!” And when I have a client that says that AND wants to part with some cash, I say “Sure.” We (my buddy and I) were trying to find the source of some odors, and looking for the odd stuff. In doing several carbon scans (e.g., GC/PID-FID, GC/PID-ECD) and comparing them to other tests (EPA TO-14/15) and tests for total non-methane organic compounds (NMOC), the mass balance was never working out. With some sleuthing, my buddy finds the siloxanes, and there are several of them, and in some cases a significant mass. My buddy starts checking other indoor air samples, and he finds more siloxanes. My samples did not exceed 34-ppbv in total, with three siloxanes. My buddy has found them as high as 61-ppbv, and as many as 6 in one air sample. What it means is that siloxanes are being used A LOT in manufactured construction materials and consumer goods; principally finished goods - not raw materials. Their use is huge and climbing, millions of pounds per year, and there is little to no toxological data on them when in combination with other NMOCs. By themselves, in isolation, they seem to be of low toxicity. But who really knows.........

Regards,

--

Geyer, PE, CIH, CSP

President

KERNTEC Industries, Inc.

Bakersfield, California

www.kerntecindustries.com

(Apologies for thoise that don't like attachments)

Interesting on the siloxane. What did you use for the method and what levels are you finding?

- see attached head pressure test (standpipe held on with plumber's putty) on a siloxane based coating on a commecial brick building. Note that both tests are on the mortar which is the weakest point. Manufacturer warranties the coating for 15 years. I did the capital equivalent calcs for 21 years based on re-coating and tuckpointing every 7 years (don't trust the manufacturer's data). It was better to coat than replace. We figured with minor cracks and the like that 7 years for the brickwork as well.

Tony

...........................................................................

" Tony " Havics, CHMM, CIH, PE

pH2, LLC

PO Box 34140

Indianapolis, IN 46234

cell

90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ 

This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

Re: Venting & Drying Brick Veneer Wall

Jeff:

Your use of a siloxane-based sealer is a great method, and it is one of the best methods to reduce water absorptivity while not substantially changing porosity of the clay body. However, from an IAQ perspective, I am finding a lot of siloxanes in indoor air samples. Something that was not present 15-years ago. Still unsure what it all means.

For what it is worth....

[Guest guest]

This is in the range I've seen - thought you talking order of mgnitude gigher.

As for Toxicology. Yes, the totality is weak but try:

18. National Toxicology Program. The Immunotoxicity of Polydimethylsiloxane (CAS No. 9016-00-6 or 63394-02-5) Contact Hypersensitivity Studies in Female B6C3F1 Mice. NTP Report Number: IMM90006 (1990).

26. Cutler, MG, Collings, AJ, Kiss, IS and Sharratt, M. A lifespan study of a polydimethylsiloxane in the mouse. Food and Cosmetic Toxicology 12:443-450, (1974).

27. Kawabe, M, Ichihara, T, Sano, M, Hagiwara, A, Tamano, S, Ogawa, K, and Shirai, T. Lack of carcinogenicity of silicone resin (KS66) in F344 rats. Food and Chemical Toxicology 43: 1065-1071 (2005).

28. Kennedy GL, Keplinger ML, Calandra JC and Hobbs EJ. Reproductive, teratologic and mutagenic studies with some polydimethylsiloxanes. Journal of Toxicology and Environmental Helath 1: 909-920 (1976).

NOAELs from 200-5,800 mg/kg.

Can you tell I've been looking at this stuff?

This is only the polymethylsiloxanes - can't find anything on others.

Tony

........................................................................... "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of GeyerSent: Wednesday, September 13, 2006 1:18 AMTo: iequality Subject: Re: Venting & Drying Brick Veneer WallTony:I am duly impressed. And to think you are putting water pressure right on the mortar joint, which I always consider a pathway. Wow! The siloxane coating appears to be working remarkable well from your photos. Thanks for sharing the photo.Regarding siloxanes in the air....We (my chemist buddy, who is a real gem) found siloxanes when conducting several IAQ investigations that were complaint driven. Like many IAQ investigations, the client says “Find something!†And when I have a client that says that AND wants to part with some cash, I say “Sure.†We (my buddy and I) were trying to find the source of some odors, and looking for the odd stuff. In doing several carbon scans (e.g., GC/PID-FID, GC/PID-ECD) and comparing them to other tests (EPA TO-14/15) and tests for total non-methane organic compounds (NMOC), the mass balance was never working out. With some sleuthing, my buddy finds the siloxanes, and there are several of them, and in some cases a significant mass. My buddy starts checking other indoor air samples, and he finds more siloxanes. My samples did not exceed 34-ppbv in total, with three siloxanes. My buddy has found them as high as 61-ppbv, and as many as 6 in one air sample. What it means is that siloxanes are being used A LOT in manufactured construction materials and consumer goods; principally finished goods - not raw materials. Their use is huge and climbing, millions of pounds per year, and there is little to no toxological data on them when in combination with other NMOCs. By themselves, in isolation, they seem to be of low toxicity. But who really knows.........Regards,-- Geyer, PE, CIH, CSPPresidentKERNTEC Industries, Inc.Bakersfield, Californiawww.kerntecindustries.com

(Apologies for thoise that don't like attachments)Interesting on the siloxane. What did you use for the method and what levels are you finding? - see attached head pressure test (standpipe held on with plumber's putty) on a siloxane based coating on a commecial brick building. Note that both tests are on the mortar which is the weakest point. Manufacturer warranties the coating for 15 years. I did the capital equivalent calcs for 21 years based on re-coating and tuckpointing every 7 years (don't trust the manufacturer's data). It was better to coat than replace. We figured with minor cracks and the like that 7 years for the brickwork as well. Tony.......................................................................... "Tony" Havics, CHMM, CIH, PEpH2, LLCPO Box 34140Indianapolis, IN 46234 cell90% of Risk Management is knowing where to place the decimal point...any consultant can give you the other 10%â„ This message is from pH2. This message and any attachments may contain legally privileged or confidential information, and are intended only for the individual or entity identified above as the addressee. If you are not the addressee, or if this message has been addressed to you in error, you are not authorized to read, copy, or distribute this message and any attachments, and we ask that you please delete this message and attachments (including all copies) and notify the sender by return e-mail or by phone at . Delivery of this message and any attachments to any person other than the intended recipient(s) is not intended in any way to waive confidentiality or a privilege. All personal messages express views only of the sender, which are not to be attributed to pH2 and may not be copied or distributed without this statement.

-----Original Message-----From: iequality [mailto:iequality ] On Behalf Of GeyerSent: Monday, September 11, 2006 6:48 PMTo: iequality Subject: Re: Venting & Drying Brick Veneer WallJeff:Your use of a siloxane-based sealer is a great method, and it is one of the best methods to reduce water absorptivity while not substantially changing porosity of the clay body. However, from an IAQ perspective, I am finding a lot of siloxanes in indoor air samples. Something that was not present 15-years ago. Still unsure what it all means.For what it is worth....