Chemical sensitivity and low-slope roofing
I am severely chemically sensitive and need a low slope, hip roof redone. Current roof is tar paper and tar and outgassed nicely. It is completely intact, no leaks. The removal of a Yankee gutter will probably damage it so the contractor feels re-roofing will be needed.
I had a very bad reaction to asphalt shingles applied to an overhang (after 2 years we had to remove them) so I am concerned about using of any asphalt/tar paper/tar products
The contractor likes EDPM so I tried that, it was awful.
TPO seems the next possible choice. Mechanically adhered seems promising but I am having a hard time getting samples from manufacturers.
I’ve read they are all different and some have EDPM incorporated. Anyone know of a TPO brand that is low or zero voc and has no EDPM ? What other “products” are associated with it? Seam cleaners (like edpm?) “insullation”?
Are there any suggestions on other options? I know metal is a possibility but getting an installer for that is tricky in my neck of the woods.
Any help appreciated
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Replies
It’s odd that you’d notice any kind of roofing material from the inside of the home. Most of the time when someone is chemically sensitive, it’s things INSIDE the structure that bother them. Your case is the first I’ve heard of someone having an issue with an EXTERIOR product. That makes me think you might want to consider improving the air sealing of your roof/ceiling so that you’ll be better protected from whatever you end up using on the roof.
You might want try something unconventional like putting a layer of metalized polyethylene sheet in the roof stackup on the interior side. The purpose of that metalized poly would be to provide a barrier to any solvents that may be offgassed from whatever roof material you end up using. Since those membrane roof products are all vapor barriers already, you won’t have any issues with drying by adding the poly that you wouldn’t have had anyone due to the roof material itself.
Bill
Thanks Bill
This is a 100 yr old house with old storm windows and sash windows,
and I am very allergic so even tiny amounts give me severe symptoms (it's not the same exactly but think of the kids who can have severe reactions to peanut butter because a tiny trace of the oil was on something they handled)
The idea of "metalized polyethelene" sounds interesting. Is the "roof stack" the hatch in the roof? we also have a chimney for our gas boiler.
How would that be placed?
Thanks
The best suggestion I could think of is EPDM, with low a low VOC glue, or depending on the specific roof design, edge terminated could work. I cannot imagine EPDM itself would have any chemical issues.
I think I would leave the house during install, and for a short time after. Perhaps rinsing the roof off, as the EPDM might have some kind of release powder on it.
Mostly any issues with EPDM would be from the chemicals used during install. They are going to be gone very quickly
Thanks I tried samples of EPDM and had significant reactions to it
I did get a sample of TPO from "Better Materials" online.
I understand that every company makes the TPO somewhat differently, some even add EDPM which would not work for me, but I am finding it near impossible to get samples from Firestome and GAF etc
That is all I've got at the moment.
I am not trying to minimize your concerns, but it seems really, really unlikely that you are reacting to the EPDM. The solvents, or the dust[maybe talc?] seem more likely, and that can be worked around.
TPO has similar types of chemical ingredients, but maybe the lower levels of solvents would work better for you
Thanks Keith
I do understand how this all may seem improbable.
Before it happened to me I would have had the same questions.
I was hoping to find a TPO free of EDPM - I understand they are all made of different chemicals. I can tolerate some chemicals for example some forms of polypropylene plastic are fine. I just have to search for something I am not getting sick with.
Someone with a similar condition used TPO but she couldn't recall the manufacturer. I am finding it really difficult to get samples so was hoping to narrow my search
Ordinary Chemicals are poisons in my system, particularly petroleum based materials, but even the turpines in pine 2x4s are unbearable. I have severe respiratory reactions - similar to asthma - as well as other physical symptoms that are disabling.
Something attached to the house is not only expensive but the reality that it cannot be removed quickly increases my need to be careful.
Hi ChemicalFam.
I agree with Bill on the air sealing work. I imagine your ceiling must be quite leaky for you to notice the off gassing of the roofing membrane inside.
Also, have you consulted with an HVAC expert to make sure that you have adequate ventilation? You should probably have a balanced system. Adequate makeup air for any exhaust fans may also prevent bath fans, range hood, etc. from pulling in air from random gaps in the envelope. An expert may also be able to help you tune your ventilation to slightly pressurize your home so no unwanted pollutants are being pulled in.
By the way, what is the actual roof pitch?
Thanks Brian
This is a 100 yr old Victorian with no HVAC. Just a hatch and a chimney on the roof.
I am on the second floor and the opening to the attic t is right on my landing. It's an old ladder and it doesn't really seal the attic opening.
I have not put anything on the roof yet, but a reaction to new asphalt shingles on a fake mansard outside my windows made me aware that anything ON the house could make me ill. (we had to remove them after 2 years, in the summer sun, with a southern exposure, the fumes were pretty horrible)
The pitch is 1:12
so options are limited
To add to what Brian said, check that any makeup air intakes aren’t right next to something that bothers you, like a plastic thing or part of the roof that heats up and smells when the sun is on it.
Bill
Thanks Bill
no HVAC
Just a boiler
How did this turn out? Did you eventually find a low VOC roofing alternative?
Hi ChemicalFam, I am was grateful to learn how much care you have for your families health. I am similarly always looking for ways to alleviate ways to build and make a healthier home for my family which are chemically sensitive to many things used in building a home. Could i reach out to share information that i find about home building, and also ask you a home building materials question! Thanks.
Hi chemicalFam, I imagine you have come up with great ideas since this question you posted here in ( In 2020). For any future reference i have some possibilities for you below. My family is also physically unable to live in a home with tar asphalt shingles, and we are educating ourselves the best we can now, with re-roofing and trying to select a material .
Primer: Liquid primer recommended for substrate by manufacturer of sheet
waterproofing material, GCPAT Perm-A-Barrier WB Primer - PERM-A-BARRIER® WB Primer is a water-based primer which imparts an aggressive, high tack finish on the treated substrate. VOC compliant—water-based, contains no hazardous or flammable solvents; Low odor.
AFM Safecoat Dynoseal - a low-odor, all-weather, waterproof, vapor-proof coating and sealer. Highly flame-resistant and temperature stable.
Safecoat Roof Guard - A water-based, low-odor roof coating for primed roofs. It is mildew and water-resistant. Used to patch, seal, or bridge hairline cracks. Serves as a good waterproofing coat.
EcoStar Aqua Guard is a waterproof underlayment. Made of polyethylene/polypropylene.
Eric