Replies

1. GBA Editor
   Martin Holladay | Jan 09, 2012 05:55am | #1

   Scott,
   1. Whether or not you need a vapor retarder on the interior of your open-cell roof foam depends on your climate. In climate zone 5 (and anywhere colder), spraying vapor-retarder paint on cured open-cell foam is recommended. This measure is not necessary for walls.

   2. Cured spray foam should be protected by a thermal barrier for fire safety. Check with your local building inspector to find out what is expected in your area. While some jurisdictions allow the use of intumescent paint as a thermal barrier, others do not. (The testing used to show the effectiveness of intumescent paints is controversial.)

   Covering cured foam with gypsum drywall is best, since all jurisdictions accept gypsum drywall as a thermal barrier.

2. 
   p8RNGbzdxv | Jan 09, 2012 06:23am | #2

   Thank you, Can I spray this paint and do you have any recomendations for product? Last, seems as though I have some "smell" associated witht he foam. Any idea on how long it takes to go. I am in the Adirondacks so I have kept the windows closed, but could open up to vent for a day or so if needed?

3. GBA Editor
   Martin Holladay | Jan 09, 2012 07:47am | #3

   Scott,
   Good luck on the smell. You should contact your spray foam installation contractor right away and let the contractor know about the smell. It might be worth documenting that fact with a dated letter to your contractor.

   Here is more information on odor problems: Spray Foam Jobs With Lingering Odor Problems.

   Yes, you can paint the foam yourself if you want (once the odor problem is resolved -- not before). Here is one brand of vapor-retarder paint: Benjamin Moore Moorcraft SuperSpec Latex Vapor Barrier Primer.

4. 
   Foamer | Jan 09, 2012 06:17pm | #4

   Scott,

   If you are covering the foam with drywall, you don't need to apply the vapor retarding paint. The painted drywall will provide enough of a barrier. It will also be sufficient as a fire barrier. Putting a radiant barrier between the foam and the drywall will be a complete waste.

5. GBA Editor
   Martin Holladay | Jan 09, 2012 07:38pm | #5

   Scott,
   If you decide to follow Torsten's advice, don't forget to paint the drywall. (Gypsum drywall is vapor-permeable.)

6. 
   p8RNGbzdxv | Jan 10, 2012 08:40am | #6

   Thank you for everyones input. The smell seems to be going away already, so I am not too concerned at this time. I will have it sheet rocked and vapor retardant paint put on. Thanks again.

7. 
   wjrobinson | Jan 10, 2012 09:14am | #7

   Scott, what company sprayed what foam? Just curious as I too live in the Adirondacks. Ajbuilderny at gmail dot com.