My walls are cold and have inadaquate insulation. Spray foam options?
I’m looking to make my house more comfortable and I’m not quite ready for new siding yet. My current siding is old and will need replaced in the next 5 years or so but I want to wait and do the windows at the same time. I will have foamboard insulation put up under the new siding. In the meantime, my walls are cold and drafty despite my house being air-sealed and the attic insulated really well (Iowa, R-60). Would open cell spray foam be a good option? I have an old house but I have drywall so I presume there’s a vapor barrier in the wall (I don’t know that for certain however). Would open cell slow rise foam injected in the walls cause difficulty for the walls to dry if moisture gets inside? Would it be better to just have cellulose or fiberglass insulation blown in? There’s already some insulation in there because there are plugs in the siding. I just believe it’s inadequate.
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Replies
Plugs in the siding likely mean you already have blown-in cellulose insulation in the walls. Get a plastic crochet hook and do some exploring around an electrical box... take off the trim plate and enlarge the gap next to the box just enough to stick the hook in and drag out some of whatever's in there. If there's any sort of fiber or shredded material then you already have insulation, and if so, I would definitely rule out injected or poured foam.
I would get an energy auditor with a blower door and a thermal imager over there to figure out what's going on. You might have air leakage that can be improved. Based on your description it seems likely to me that you should wait until you do the exterior renovation to try to change the insulation picture.
Jason,
I agree 100% with David's advice. The time to improve the insulation levels of your walls is when you install new siding. In the meantime, it's worth hiring a contractor with a blower door to help you find your air leaks.