Re: Mold on cinder block walls

[Guest guest]

,

I would not equate applying a sealant to a wet cinder block foundation wall with "painting over or covering up mold growth". I probably would have advised a homeowner who called me in to look at growth on a foundation wall to correct roof and site drainage deficiencies and apply an appropriate sealant to the foundation block. It is not applied for the purpose of covering up mold growth. It is applied to substantially reduce the amount of water evaporating from the surface of the wall into the basement or crawl space. Mold does not grow on cinder block. It grows on the organic dust or biofilm or paint on the cinder block.

What is the purpose of testing the growth? What are you going to do with the results when you get them from the lab?

My advice to you, if you are qualified, is to offer the service of helping the homeowner deal with the underlying cause(s) of the wet foundation wall and related indoor moisture and never mind about what kind of mold is underneath the newly applied damp-proof foundation coating.

Steve Temes

Dear Group,

I have been asked by a client to test for mold on a cinder block wall

that was recently painted. My client suspects the previous owner of

the house painted over or covered up mold growth on the wall. Does

anybody know of a way to collect a sample for mold on a freshly

painted wall? I am not sure if scraping off the paint would work very

well because it is relatively new and is well adhered to the wall.

Has anybody experienced this type of project in the past or have any

suggestions?

Thanks,

Gerike

www.esginfo.com

[Guest guest]

I've had luck with swab sampling and tape lift sampling. But the more important question is whether or not the moisture levels are conducive to mold growth. Is there any evidence of efflorescence? Have you taken any concrete moisture tests? What are the ambient conditions of the room? If moisture is penetrating the walls, or if RIH is very high or the room is not sufficiently heated and dew point conditions are occurring mold will eventually colonize paint. Determining if there is a moisture problem will be should be the first step. AKS

Mold on cinder block walls

Dear Group,I have been asked by a client to test for mold on a cinder block wall that was recently painted. My client suspects the previous owner of the house painted over or covered up mold growth on the wall. Does anybody know of a way to collect a sample for mold on a freshly painted wall? I am not sure if scraping off the paint would work very well because it is relatively new and is well adhered to the wall. Has anybody experienced this type of project in the past or have any suggestions?Thanks, Gerikewww.esginfo.com

[Guest guest]

Amy & Steve,

The moisture issues are being addressed and I agree with your

statements. My client believes the previous owner new there was

mold growth on the walls and did not disclose it on the disclosure

form when the house was sold. I know it would be hard to prove that

the previous owner new there was mold growth there prior to sealing

the walls. My client wanted to know if there was a way to sample

and try to determine if there was mold on the wall before it was

sealed. But I am not sure of a way to do that.

Thanks for the feedback.

>

> ,

>

> I would not equate applying a sealant to a wet cinder block

foundation wall

> with " painting over or covering up mold growth " . I probably would

have advised

> a homeowner who called me in to look at growth on a foundation

wall to

> correct roof and site drainage deficiencies and apply an

appropriate sealant to the

> foundation block. It is not applied for the purpose of covering

up mold

> growth. It is applied to substantially reduce the amount of water

evaporating from

> the surface of the wall into the basement or crawl space. Mold

does not grow

> on cinder block. It grows on the organic dust or biofilm or paint

on the

> cinder block.

>

> What is the purpose of testing the growth? What are you going to

do with the

> results when you get them from the lab?

>

> My advice to you, if you are qualified, is to offer the service of

helping

> the homeowner deal with the underlying cause(s) of the wet

foundation wall and

> related indoor moisture and never mind about what kind of mold is

underneath

> the newly applied damp-proof foundation coating.

>

> Steve Temes

>

> In a message dated 10/27/2008 2:10:31 PM Eastern Daylight Time,

> bg@... writes:

> > Dear Group,

> > I have been asked by a client to test for mold on a cinder block

wall

> > that was recently painted. My client suspects the previous owner

of

> > the house painted over or covered up mold growth on the wall.

Does

> > anybody know of a way to collect a sample for mold on a freshly

> > painted wall? I am not sure if scraping off the paint would work

very

> > well because it is relatively new and is well adhered to the

wall.

> > Has anybody experienced this type of project in the past or have

any

> > suggestions?

> > Thanks,

> > Gerike

> >

> > www.esginfo.com

> >

> >

> >

>

[Guest guest]

It may be that you are asking the wrong questions here; getting useful answers is highly unlikely when you ask the wrong questions.

When there is a mold problem with concrete or cinder block walls, you must first ensure that there is a virtually-fault-free seal at the top of the wall. The connected hollow core gaps in block walls are often the location where dust and moisture combine to grow mold, bacteria, etc., and generously give the by-products back to the householder.

Have you checked the seal at the top of the wall?

Jim H. White

System Science Consulting

Mold on cinder block walls

Dear Group,I have been asked by a client to test for mold on a cinder block wall that was recently painted. My client suspects the previous owner of the house painted over or covered up mold growth on the wall. Does anybody know of a way to collect a sample for mold on a freshly painted wall? I am not sure if scraping off the paint would work very well because it is relatively new and is well adhered to the wall. Has anybody experienced this type of project in the past or have any suggestions?Thanks, Gerikewww.esginfo.com

[Guest guest]

,

How then do you transfer the spores from gauze to slides, aso using alcohol?

I've also heard that 91% rubbing alcohol can be used to make spores

collected on tape lifts easier to visualize. At least that is what I remember

(it was a fairly long time ago)

I should have asked more about the specifics.

Do people typically use stains when they are examining spores or bulk samples?

> :

>

> I can see by the posts that no one is directly answering your question. Bad

> Group!

>

> Since most paint films now being sold to the general public are latex and

> water-based, I have had some good success sampling with cotton gauze soaked

> in isopropal alcohol as a solvent – the stronger the IPA the better. If

> sufficient elbow-grease is applied with the gauze and solvent, the paint

> film will dissolve and the paint film and underlying spores, if present,

> will be captured on the gauze.

[Guest guest]

,

Thanks for answering my question, you hit the nail on the head. I

will take into account your suggestions.

Thanks again,

-- In iequality , Geyer wrote:

>

> :

>

> I can see by the posts that no one is directly answering your

question. Bad

> Group!

>

> Since most paint films now being sold to the general public are

latex and

> water-based, I have had some good success sampling with cotton

gauze soaked

> in isopropal alcohol as a solvent ­ the stronger the IPA the

better. If

> sufficient elbow-grease is applied with the gauze and solvent, the

paint

> film will dissolve and the paint film and underlying spores, if

present,

> will be captured on the gauze. Hexane, as a solvent, also works;

but Hexane

> is harder to acquire. Please note, this will leave bald spots

(i.e.,

> Holidays).

>

> Now for the $64 question.......If you find spores, what does that

mean? Was

> it pre-existing ­ because the original surface was definitely not

sterile!

> Just what concentration (threshold) of spores on the gauze will

you consider

> to be elevated, versus normal, versus?????? Answer this question

BEFORE

> sampling!

>

> And just where on this block wall do you suppose to collect the

> sample?......One every 10-sq.ft.? One every 100? One every

1,000? The

> more the better at finding what you are looking for.

>

> Mover, paint films stick to surfaces that are clean, dry, and

sound. If, in

> fact, the surface of the block wall was not clean (it was covered

with mold

> products) and it was not dry (moisture was contained therein that

supported

> the mold growth), then I believe that the paint film would not be

well

> adhered to the surface. Thus, I would try scraping before I would

use the

> solvent sampling method. If I was to easily scrape-off some of

the paint

> film, then I would tend to concluded that the surface warranted

> prep.....because it might not be clean, dry, and sound. Then,

maybe,

> proceed to step no. 2 ­ sampling.

>

> For what it is worth.....

>

>

>

>

>

>

> >

> >

> >

> > Dear Group,

> > I have been asked by a client to test for mold on a cinder block

wall

> > that was recently painted. My client suspects the previous

owner of

> > the house painted over or covered up mold growth on the wall.

Does

> > anybody know of a way to collect a sample for mold on a freshly

> > painted wall? I am not sure if scraping off the paint would

work very

> > well because it is relatively new and is well adhered to the

wall.

> > Has anybody experienced this type of project in the past or have

any

> > suggestions?

> > Thanks,

> > Gerike

> >

> > www.esginfo.com

> >

> >

> >

>

[Guest guest]

and ,

I agree with you all on the question/purpose of testing ? , and I am

also of the opinion that a dry, painted, compact wall made of

inorganic materials with a well adhered paint do not constitute a

serious mold problem as long as there is no mold growing on the

visible surfaces.

Remember that sampling is nothing but a tool to help you answer a

question (or test your hypthesis)

If you assume that a simple sampling will answer all questions like:

Is this normal ?

Can it spread out into the air ?

Can it make me sick ?

Is it covering all of the wall ?

Have it been there more than 2 years ?

Etc, etc, etc

..... then you are excpecting way to much....

But if the question asked is simply:

Have mold been GROWING on the wall BEFORE it was painted ?

Then you should take a material sample from the wall. (maybe two or

three, (top, middle, bottom ?)

Be sure to get some of the paint and the material attached to it.

Use a knife or scalpel. Put it in a paper bag and send it to a

laboratory with a good microscopist/microscope and ask them to look

for HYPHA in/inside the paint and /or in the material beneath.

If the laboratory find hypha only on the " backside " of the paint

(maybe even hypha penetrating the pores of the material beneath the

paint) you can conclude that there has been mold growing on the

surface before it was painted.

Of course if they do not find any hypha, you can only conclude that

in these 3 places of the wall there was no growth, and that this is a

good indication that such growth has not occured in the past.

The spores are not relevant to answer the question asked in this

context. And it is not relevant that the environment is not " sterile "

I guess a laboratory would charge you a bit more than $64.... but it

should not be that expencive to do. Here in Norway it would cost you

about $500 for three samples including the report :-)

Ole

>

> >

> >

> >

> > Dear Group,

> > I have been asked by a client to test for mold on a cinder block

wall

> > that was recently painted. My client suspects the previous owner

of

> > the house painted over or covered up mold growth on the wall.

Does

> > anybody know of a way to collect a sample for mold on a freshly

> > painted wall? I am not sure if scraping off the paint would work

very

> > well because it is relatively new and is well adhered to the wall.

> > Has anybody experienced this type of project in the past or have

any

> > suggestions?

> > Thanks,

> > Gerike

> >

> > www.esginfo.com

> >

> >

> >

>

[Guest guest]

,

If people are experiencing health issues from mold in a home with a

painted block foundation, it is not very likely that the source of the

mold is the foundation since the mold is " encapsulated. " (You should

also make sure that the cavities at the top of the foundation are

sealed as these can be the source of spores.)

If the basement is damp or there has been relative humidity over

75-80% for extended periods and there is fiberglass ceiling

insulation, it is likley that the insulation is quite contaminated

with mold growth and mold eating mites.

I noticed on your web site (www.esginfo.com) that you advertise

Humidex. In most climates in this country, exhaust only ventilation is

NOT a solution to basement humidity control. Dehumidification where

needed in basements can ONLY be accomplished through cooling air.

May

May Indoor Air Investigations LLC

Tyngsborough, MA

www.mayindoorair.com

www.myhouseiskillingme.com

> 2a. Re: Mold on cinder block walls

> Posted by: " LiveSimply " quackadillian@...

> Date: Wed Oct 29, 2008 5:00 pm ((PDT))

>

>>> > Dear Group,

>> > I have been asked by a client to test for mold on a cinder block

> wall

>> > that was recently painted. My client suspects the previous

> owner of

>> > the house painted over or covered up mold growth on the wall.

> Does

>> > anybody know of a way to collect a sample for mold on a freshly

>> > painted wall? I am not sure if scraping off the paint would

> work very

>> > well because it is relatively new and is well adhered to the

> wall.

>> > Has anybody experienced this type of project in the past or have

> any

>> > suggestions?

>> > Thanks,

>> > Gerike

>> >

>> > www.esginfo.com

[Guest guest]

That's what I was asking-

I could call the person who told me that alcohol is sometimes used, if

nobody finds out..

She is a mycologist and has extensive experience doing mold

identification. But I don't want to bother her if the answer is easily

findable on the web.

Also, when people do fungal microscopy, do they use stains, (besides

KOH) and which stains are used when..

If nobody is willing to share their techniques, is there a handy

reference anywhere?

> Quack:

>

> How then do you transfer the spores from gauze to slides?.....

>

> The same way they transfer from swabs......but I will let the lab folks

> explain this so I do not butcher the explaination and get it wrong.

> Wei??????

>

>

>

>

>

>

>

>

>

> ,

>

> How then do you transfer the spores from gauze to slides, aso using alcohol?

>

> I've also heard that 91% rubbing alcohol can be used to make spores

> collected on tape lifts easier to visualize. At least that is what I

> remember

> (it was a fairly long time ago)

>

> I should have asked more about the specifics.

>

> Do people typically use stains when they are examining spores or bulk

> samples?

>

> On Tue, Oct 28, 2008 at 11:50 PM, Geyer <megeyer@...

> <mailto:megeyer%40atg1.com> > wrote:

>> :

>>

>> I can see by the posts that no one is directly answering your question.

>> Bad

>> Group!

>>

>> Since most paint films now being sold to the general public are latex and

>> water-based, I have had some good success sampling with cotton gauze

>> soaked

>> in isopropal alcohol as a solvent – the stronger the IPA the better. If

>> sufficient elbow-grease is applied with the gauze and solvent, the paint

>> film will dissolve and the paint film and underlying spores, if present,

>> will be captured on the gauze.

>

>

>