Interior basement wall insulation – options after framing has started
BryanA99
| Posted in Green Building Techniques on
So, we decided late in the building process to finish some of the basement. I forgot to specify that rigid foam be applied to the interior basement wall, and the interior framing has already been done. I’m still kicking myself for the oversight. I’m sure the builder is planning to go with ‘code’ and put in fiberglass insulation in between the studs against the concrete wall.
So…what options do I have at this point to minimize future moisture problems. I can specify paperless drywall. Might be able to get rigid foam cut and applied between the studs.
Thanks in advance for your suggestions!
– Bryan
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Replies
Bryan,
You have two choices: closed-cell spray polyurethane foam, or else remove the stud walls and start from scratch (so that a continuous layer of rigid foam can be attached to the wall).
The spray foam option will work much better if none of the studs are touching the concrete. If your builder installed your studs tight to the concrete, I would certainly remove the studs and start over.
Thank you Martin. I guess I knew what the reply would be but needed to hear it! I'm going to talk to the builder right away. I do believe the studs are against the concrete and just found out that they zipped in the electrical as well. So removing studs is sounding expensive.
In this case, would a flash of spray foam to seal the concrete and cover the studs against the wall be a less than optimal, but acceptable option? We have under slab and slab edge foam and exterior sprayed waterproofing. Thanks!
Bryan- sprayed closed cell would still be better at this point than fiberglass, which in my opinion would be useless and not provide much, if any, value. In addition, the expense of removing the stud wall and electrical and then rebuilding would probably negate any savings. I would spray 2-3"...no real need to fill the cavity 100%.
Good luck..
The walls could be moved in minutes. Only PT wood contacting cement. Drop the walls and add foam sheet if that's what you want. If not the wrong way has been done many times with and without future problems. A dry cellar has few problems. A wet cellar is nothing but problems.
Thanks to Bruce, AJ and Martin. I'll explore options with the builder. Maybe moving the walls even with trade work already in won't be a biggie. Otherwise, I'll look into spray foam. Still kicking myself...but what's done is done and will either be undone, or we'll work around it. Just hoping to increase the odds of long term dry basement. Thanks again!
Hello,
Which option did you go with in completing the basement? Did you remove the frame or use the spray foam? Has it held up?