Blanket insulation in basement
Mizoman
| Posted in General Questions on
The builder installed a roll batt blanket insulation in an unfinished basement covering poured in place concrete walls. I am curious on opinion as to whether leave it and frame in front of it or remove it and frame off wall and insulate with closed cell spray foam.
Can the blanket insulation be left?
Thanks,
Tim
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Replies
Tim,
If your climate is dry and relatively warm, and if your basement walls are waterproofed and dry, the type of insulation you describe can work. If your climate is cold, and the basement is damp or the weather is humid, the insulation is risky.
If it were my house, I'd get rid of the insulation and start from scratch. But if that approach seems wasteful to you, pull up some of the insulation to investigate. Look for signs of condensation or mold, and investigate whether anything smells bad.
Thanks for the quick response. I am in the Midwest so we have great temperature swings. The corners on the basement on the bottom of the insulation seem damp but there is no signs of water infiltration anywhere. I am concerned it is picking up moisture from the slab.
Sounds like removing it might be the best solution.
The midwest is a big place, spanning US climate zones 2-7. Could you be a bit more specific, so that the recommendations can be climate-specific?
Closed cell foam may or may not be the best or the most cost effective solution.
Omaha, Nebraska