Best materials and application to cover sprayed urethane insulation for fire protection
GBA Editor
| Posted in Energy Efficiency and Durability on
For a small to medium sized steel building already coated with urethane and also for the inside of above ground foundations not yet coated.
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I would check with your state fire marshal to see what is approved and required. I understand this varies by state.
My interpretation of the requirements, which our inspectors are agreeing with here in NC, is that there needs to be a layer of drywall between the foam and any accessible storage space mostly to prevent air from getting to the foam to support combustion. So we have been framing and sheet-rocking storage rooms in the attics where they are accessible by pull down staircase or access door. In a large attic this might be a 12' x 8' area, just enough for Christmas decorations and old suitcases. Beyond that the rest of the attic is just sealed off by that storage area from air and any access panel for service is screwed in place with Philips head screws rather than accessed by a hinged door. A similar approach could be done in a crawl.
My sense is that the "ignition barrier paints" are mostly snake oil.