Guest guest Posted November 11, 2011 Report Share Posted November 11, 2011 Don, Are you sure that the attic exhaust fan is causing attic air containing formaldehyde (etc.) to enter the living area, or is it creating negative pressure in the living area that is pulling formaldehyde-contaminated air in from wall cavities or elsewhere? If so, provide a path of least resistance to the outdoors. That is, make sure the make-up air for the air being pulled into the attic from the living space is of good quality. You may have more attic exhaust than you need. Especially in the heating season, you only need to make sure the house isn't negative relative to the attic. You don't need to move large volumes of air. Assuming you aren't exhausting air deliberately from the living space or from underneath it (basement or crawl), additional sources of negative pressure in the house would be from the return ductwork in a forced air system, or the venturi effect from cross-ventilation with windows open. Sealing of all ceiling plane communication between the attic and living space can be difficult. You can use inexpensive smoke testing (Wizard Stick from www.zerotoys.com) to figure out some of the air leakage and air current pathways. You need to ventilate the house, meaning indoor/outdoor air exchange in the living areas. Keep windows open or consider retrofitting a whole-house ventilation (ERV) system. I will assume that when you refer to the mold under the sink being problematic, that you are reacting to low levels of MVOCs. Sorry, I don't know anyone I can recommend in your area who specializes in working with people with chemical sensitivities, but you can search the IAQA website (www.iaqa.org) for local consultants and interview them. They shouldn't need to test if you can tell them where the problem areas are. Consider that this is your first heating season in the house. Formaldehyde or other chemical offgassing may be occurring at a higher rate due to the heating system being in operation which warms building materials as well as the air. Thanks for your post. Many of my clients have similar chemical hypersensitivity issues (often to MVOCs at very low concentrations), however there are a lot of professionals in the IAQ and medical fields who don't have any appreciation for the types of health effects you describe. Steve Temes AirWays Environmental Svcs. Red Bank, NJ In a message dated 11/10/2011 8:48:19 PM Eastern Standard Time, no_reply writes: I just recently purchased (in August) a home in Mount Vernon WA. I have chemical intolerances. I believed the only issues I would have to remedy were the mold from leak under the kitchen sink and the new carpet. I have Reactive Airway Disorder and certain chemicals trigger bronchitis and other inflammatory reactions. I was surprised when the removal of the carpet did not end the bronchitis. It was when I went into the attic I realized that I was reacting to the formaldehyde in the OSB in the sub roof. A contractor friend recommended putting a gable fan to remove gases. The gable fan seemed to create a pressure that made the gases enter the interior even more strongly. I hired different handy men to seal the exposed OSB (between the wood lathes to which the original cedar shakes had been nailed. There is a gap between the lumber lathes). I had two coats of AFM Safe Seal and a coat of a no VOC primer applied. The formaldehyde continues to be a problem. It is now cold here and the fan only comes on when it is about 60 degrees. I am not sure how to remedy this issue now. I need to find someone in my area who can give a consultation. BTW, the house has no eve vents or roof vents. The venting is solely through the two gable vents. This is a Japanese-like style roof with too levels. The lower level has zero venting. So when the heat creates formaldehyde gas off there really is no place upward for the gas to go (since the roof itself acts as a vapor barrier). This is a great architecturally designed home. I believe when they put the new roof on (before resale), they did not want to harm the aesthetics of the roof design. I have been told that it is now code to have roof and eve vents. Does anyone active on this list live in northwest Washington State (Bellingham, Seattle, Mount Vernon)? I want to create a thoughtful remedy for this problem. I am looking for someone who may have IAQ expertise. I can find someone to do the work. BTW, the insulation in the attic is pathetic (some rock wool and two inch paper batted fiberglass) I need to do some research for tolerable insulation ( Mansville and Skytech have been recommended as options). Thanks for any information, leads, or help you may render. Don Paladin WSMCSN Owner Sunergos2001@... http://wsmcsn.s5.com p.s. I have been an inactive member of this list for years. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 12, 2011 Report Share Posted November 12, 2011 Don: OSB is advertised as having very low formaldehyde emissions. http://osbguide.tecotested.com/faq10 If you have formaldehyde emissions from your OSB, perhaps it was made in a non-standard manufacturing facility. As for the gable fan, does it exhaust gases from the attic or does it blow fresh air in? Your description implies that outside air is being blown in through one gable vent and exhausted through the other gable vent. It seems to me that it if both gable vents are the same size there should be insignificant positive pressure to cause polluted air to be blown through the ceiling into your living space. I don’t understand how a two-level roof with one attic could create a problem. Are the two attics unconnected to each other? Norm Gauss From: iequality [mailto:iequality ] On Behalf Of sunergos2001Sent: Thursday, November 10, 2011 4:52 PMTo: iequality Subject: Remedy attic air quality issues I just recently purchased (in August) a home in Mount Vernon WA. I have chemical intolerances. I believed the only issues I would have to remedy were the mold from leak under the kitchen sink and the new carpet. I have Reactive Airway Disorder and certain chemicals trigger bronchitis and other inflammatory reactions. I was surprised when the removal of the carpet did not end the bronchitis. It was when I went into the attic I realized that I was reacting to the formaldehyde in the OSB in the sub roof. A contractor friend recommended putting a gable fan to remove gases. The gable fan seemed to create a pressure that made the gases enter the interior even more strongly. I hired different handy men to seal the exposed OSB (between the wood lathes to which the original cedar shakes had been nailed. There is a gap between the lumber lathes). I had two coats of AFM Safe Seal and a coat of a no VOC primer applied. The formaldehyde continues to be a problem.It is now cold here and the fan only comes on when it is about 60 degrees. I am not sure how to remedy this issue now. I need to find someone in my area who can give a consultation. BTW, the house has no eve vents or roof vents. The venting is solely through the two gable vents. This is a Japanese-like style roof with too levels. The lower level has zero venting. So when the heat creates formaldehyde gas off there really is no place upward for the gas to go (since the roof itself acts as a vapor barrier). This is a great architecturally designed home. I believe when they put the new roof on (before resale), they did not want to harm the aesthetics of the roof design. I have been told that it is now code to have roof and eve vents. Does anyone active on this list live in northwest Washington State (Bellingham, Seattle, Mount Vernon)? I want to create a thoughtful remedy for this problem. I am looking for someone who may have IAQ expertise. I can find someone to do the work. BTW, the insulation in the attic is pathetic (some rock wool and two inch paper batted fiberglass) I need to do some research for tolerable insulation ( Mansville and Skytech have been recommended as options). Thanks for any information, leads, or help you may render.Don Paladin WSMCSN OwnerSunergos2001@...http://wsmcsn.s5.comp.s. I have been an inactive member of this list for years. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 13, 2011 Report Share Posted November 13, 2011 Hi Norm, Thank you for your reply. First, I do not know where the roofing contractor obtained the osb sheeting for this roof. Please understand that I am " hypersensitive " to formaldehyde. I am in the ONE PERCENT (not the billionaire one percent) that is hypersensitive to formaldehyde. This was a result of buying a mobile home in 1976 laden with the stuff. From that long term exposure I developed Reactive Airway Disorder (bronchial and mucus lining inflammation). Those standards you linked to do not say there is zero formaldehyde in the OSB. (Please note Monsanto says that Roundup is non-toxic and not harmful ... but it is very toxic for me). My pathways for detoxifying biocides (borates, pesticides, formaldehydes, etc.) have been severely damaged. The house is a custom built and architecturally designed home built in 1960. I know the source of the environmental trigger is in the attic because my level of reaction went up very high the two or three times I have tried to enter it. There has been no new insulation added since 1960 (walls or attic). There has been no painting done recently (within at least a year). I had the new carpet removed from the slab floor. The slab is well drained with gutter being drained to the storm sewer. The only mold I detect is from a leak under the sink in the kitchen.The leak has been repaired. I will need to seal the cabinet that emits mold odor. Through deductive reasoning, that left the source being the OSB. Please understand that my tolerance level of formaldehyde is pretty near zero. The roof is like a Japanese style roof. There is a higher (like a pop up in the center) roof with a higher pitch. The lower level roof has a lower pitch. The only venting is being done in the the higher pitched roof. There are NO eves or roof vents. There is only ONE attic connected with this bi-level roof. When the lower roof has gases, there really is not easy venting access except through air circulation through central pop-up roof where the vents are. It may be hard to visualize because this is a custom designed roof. I had an electrician put a gable fan on the east facing gable (the highest point in the pop-up roof). The west gable vent remains open to air flow. I am assuming he attached the fan so that it would blow air out of the attic. This would cause it to suck air from the other vent and cracks in the house. My goal was to create a pressure so that air flow would be able to access gases in the lower roof. The design of the roof may not have been amendable to such a plan. If you think of the lower pitched roof as being an envelop open to the larger roof, that might help explain the air flow problem. There are ZERO vents in the lower roof pitch. The house is not a square box. The bedroom is like a rectangle attached to a larger rectangle. Maybe this is only confusing. As you can see, it is not an easy venting issue. My brother in law who was a contractor (now retired) recommended putting in roof vents in the lower roof. The only issue I have with that is that will the roof vents change the IAQ so that ALL attic air is being vented upward and outward. That is why the question about IAQ and the attic. I want to be prudent in resolving this issue. Again, thank you for your response. Don Paladin WSMCSN http://wsmcsn.s5.com > > Don: > > > > OSB is advertised as having very low formaldehyde emissions. > > > > http://osbguide.tecotested.com/faq10 > > > > If you have formaldehyde emissions from your OSB, perhaps it was made in a > non-standard manufacturing facility. > > > > As for the gable fan, does it exhaust gases from the attic or does it blow > fresh air in? Your description implies that outside air is being blown in > through one gable vent and exhausted through the other gable vent. It seems > to me that it if both gable vents are the same size there should be > insignificant positive pressure to cause polluted air to be blown through > the ceiling into your living space. > > > > I don't understand how a two-level roof with one attic could create a > problem. Are the two attics unconnected to each other? > > > > Norm Gauss > > > > > > From: iequality [mailto:iequality ] On Behalf > Of sunergos2001 > Sent: Thursday, November 10, 2011 4:52 PM > To: iequality > Subject: Remedy attic air quality issues > > > > > > I just recently purchased (in August) a home in Mount Vernon WA. I have > chemical intolerances. I believed the only issues I would have to remedy > were the mold from leak under the kitchen sink and the new carpet. I have > Reactive Airway Disorder and certain chemicals trigger bronchitis and other > inflammatory reactions. I was surprised when the removal of the carpet did > not end the bronchitis. It was when I went into the attic I realized that I > was reacting to the formaldehyde in the OSB in the sub roof. A contractor > friend recommended putting a gable fan to remove gases. The gable fan seemed > to create a pressure that made the gases enter the interior even more > strongly. I hired different handy men to seal the exposed OSB (between the > wood lathes to which the original cedar shakes had been nailed. There is a > gap between the lumber lathes). I had two coats of AFM Safe Seal and a coat > of a no VOC primer applied. The formaldehyde continues to be a problem. > > It is now cold here and the fan only comes on when it is about 60 degrees. I > am not sure how to remedy this issue now. I need to find someone in my area > who can give a consultation. BTW, the house has no eve vents or roof vents. > The venting is solely through the two gable vents. This is a Japanese-like > style roof with too levels. The lower level has zero venting. So when the > heat creates formaldehyde gas off there really is no place upward for the > gas to go (since the roof itself acts as a vapor barrier). This is a great > architecturally designed home. I believe when they put the new roof on > (before resale), they did not want to harm the aesthetics of the roof > design. I have been told that it is now code to have roof and eve vents. > > Does anyone active on this list live in northwest Washington State > (Bellingham, Seattle, Mount Vernon)? I want to create a thoughtful remedy > for this problem. I am looking for someone who may have IAQ expertise. I can > find someone to do the work. BTW, the insulation in the attic is pathetic > (some rock wool and two inch paper batted fiberglass) I need to do some > research for tolerable insulation ( Mansville and Skytech have been > recommended as options). > > Thanks for any information, leads, or help you may render. > Don Paladin WSMCSN Owner > Sunergos2001@... <mailto:Sunergos2001%40yahoo.com> > http://wsmcsn.s5.com > > p.s. I have been an inactive member of this list for years. > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 19, 2011 Report Share Posted November 19, 2011 Steve, Wouldn't you always be creating a negative pressure effect in a house by opening windows? > > > You may have more attic exhaust than you need. Especially in the heating > season, you only need to make sure the house isn't negative relative to the > attic. You don't need to move large volumes of air. Assuming you aren't > exhausting air deliberately from the living space or from underneath it > (basement or crawl), additional sources of negative pressure in the house would be > from the return ductwork in a forced air system, or the venturi effect from > cross-ventilation with windows open. > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 19, 2011 Report Share Posted November 19, 2011 I'm not an indoor air quality professional but had an air leaky attic. It's possible if there is a lot of air leakage between house and attic that fan is creating a lot of air movement in house, perhaps sucking it out of attic but perhaps make up air is coming from down in house. In order for that air to leave house out attic, it needs makeup air which it could be pulling down from attic also or from some other unclean area of house, wall cavities, etc. I had a lot of air leakage betw attic and house that caused problems with too much air movement betw unclean areas, basement, attic and interior walls. Fan may have just increased the movement of gasses all through house. > > I just recently purchased (in August) a home in Mount Vernon WA. I have chemical intolerances. I believed the only issues I would have to remedy were the mold from leak under the kitchen sink and the new carpet. I have Reactive Airway Disorder and certain chemicals trigger bronchitis and other inflammatory reactions. I was surprised when the removal of the carpet did not end the bronchitis. It was when I went into the attic I realized that I was reacting to the formaldehyde in the OSB in the sub roof. A contractor friend recommended putting a gable fan to remove gases. The gable fan seemed to create a pressure that made the gases enter t Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 19, 2011 Report Share Posted November 19, 2011 P.S. to my post. I notice you say fan put in highest part of roof. Research says that formaldehyde is heavier than air so settles to low areas so perhaps if fan is in highest are, it is not venting out the formaldehyde. I had professional air sealing done in my attic to solve air leakage problems betw attic and house. http://epa.gov/Region7/education_resources/teachers/ehsstudyehs10.htm http://epa.gov/Region7/education_resources/teachers/ehsstudy/ehs10.htm >> > Hi Norm, > Thank you for your reply. F Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 21, 2011 Report Share Posted November 21, 2011 Jim, I was suggesting a possibility that I hoped professionals here would comment on. I know I'm not an expert but as far as references go, this is from the epa saying formaldehyde would seek low places. This may be over time and in still air as you suggest but it wasn't from a poor reference. > > Barb > Gases tend to mix quite well in large spaces and it is very unlikely that the formaldehyde 'settles' because it is heavier than air (even if it was from the underside of the sloped roof). Removing air from the attic removes formaldehyde that is mixed in with the air. For seconds to minutes after a gas is locally introduced it will not be in equilibrium, but after hours the mixing is usually very good indeed. A little science can mislead badly. Check the background of your sources carefully. > > Jim H. White SSC > > Re: Remedy attic air quality issues > > I notice you say fan put in highest part of roof. Research says that formaldehyde is heavier than air so settles to low areas so perhaps if fan is in highest are, it is not venting out the formaldehyde. I had professional air sealing done in my attic to solve air leakage problems betw attic and house. > > > http://epa.gov/Region7/education_resources/teachers/ehsstudy/ehs10.htm Quote Link to comment Share on other sites More sharing options...
Guest guest Posted November 21, 2011 Report Share Posted November 21, 2011 Yes, I can see a tremendous number of variables. Complicated. > > Barb > As Steve says there are several ways that air is sucked out by open windows, depending on their orientation to the wind. If wind comes directly at a wall, that wall and the openings in it will be pressurized compared to the average outside pressure (except near the corners). All of the other surfaces will be depressurized; the most Quote Link to comment Share on other sites More sharing options...
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