Is pour foam a practical solution for this issue?
There is a niche above my covered entry way. I guess you could think of it as a small flat roof or a cold floor (with drywall on the conditioned slide and sheathing on the exterior) . Because of a miscommunication, the insulation contractor did not foam this area while treating other areas of the house.
My energy rater suggests drilling a series of 2 inch holes in the drywall and using a kit to spray foam the entry way from above. I am fine with this idea but am wondering if pourable foam would do a better job of filling the void. (Someone on GBA asks a similar question but received no comments.) Online sources offer a variety of open and close cell formulations. I image you have to be careful about mixing the two parts correctly and completing your pour before the reaction gets too far along.
Is this a bad idea? Should I stick a more traditional solutions such as a Touch and Seal kit?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Foam pours are a bit risky- once installed can't be changed or fixed without major demolition. (It glues everything together.) You have a little bit more control if using a spray kit, but that's a bit hard to get right without pulling down the gypsum.
I don't have a clear mental picture of the assembly that is being insulated.
Hi Dana,
After more reading, I was having the same concerns about trying to manage a pour so there were no void or blowouts. Here is a photo that might help you visualize the entry way.
So it's fully conditioned space on the top side of the assembly, and an outdoor ceiling on the bottom side.
There's no risk to just pumping it full of blown cellulose or fiberglass in your climate. It's essentially the same as insulating a floor over a pier foundation or crawlspace. IRC code min would be R19 in zone 3A, but it's fine to go higher. DIY cellulose with a rental blower would be pretty easy and effective. Even if you can't quite get to 3lbs density it's still very air-retardent. Hopefully the light fixture is gasketed air tight and rated for insulation contact?
Thanks, Dana.
That would be simpler. I will check out the fixture to see if it can handle the insulation.
If the fixture needs to be replaced, a surface mount LED downlight in a standard electrical box would allow for thicker insulation and would be easy to air-seal.