Question

What is the least toxic subflooring or vapor barrier to keep roofing fumes out of the house?

Asked by Dee Larosh
Overland Park, KS

I am environmentally ill now for 24 years. We are trying to get a new roof put on without causing me trouble. They still use the pressboard as subflooring, and that will give me problems. Can you recommend anything we can use to put under subflooring to keep roofing fumes from traveling down into the home but not cause any moisture buildup to occur? I have heard of sharkskin but do not know what it is as of yet.

Answer

Martin Grohman

Answered by Martin Grohman

Biddeford, ME

GAF Materials Corp

February 10, 2011

I am not sure of a product that would go under roof decking, but it's worth noting that formulations of OSB and other wood panel products used for roof decking have dramatically reduced emissions or offgassing in recent generations.

  • For your project, you may wish to ask for a brand that has especially good performance in this area.
  • Also, your attic is the one place in the home that you actually want to be drafty, so that moisture and stale air can escape.

When you're having your roof replaced, that's the time to get a high performance ridge vent installed, and be sure ventilation is adequate (and matched) at both the ridge and under the eaves, and that the vents at the eaves are not blocked by insulation.

GAF has a line of Cobra ridge vents that offer very high air flow, as well as a breathable roofing underlayment called Deck Armor.

Also, if your home has a hip roof or other design with a limited ridge line, you can add solar powered attic vents.

 

For more information:

Read "I'm concerned about toxic offgassing from OSB subflooring and roofing. Are safer products available?", a Q&A answered by Ian MacLeod.

Read "How effective are the different attic ventilation methods? I read mixed reviews, and many have a commercial bias.", a Q&A answered by Danny Kelly. 

Tagged In: vapor barrier

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