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Walls have no insulation!

I have been blessed with a recent remodel before moving in to a house. This blessing has turned in to project after project because shortcuts(no code violations to speak of). The house is one of that added rooms as needed and has various construction styles in use. During the remodel in areas where block was the outside wall surface a separate 2x4 wall was built in front of the block (about a 2x4 width away from it). When they put up the wallboard they didn't insulate behind it. Now that Summer has hit full tilt here I need advice. I know these walls need insulation(infrared thermometer indicates that the wall surface is only about 10 to 20 % less than the outdoor temp) but what is going to be the least intrusive mode of installation(trying to avoid tearing out walls and redoing).

Re: Walls have no insulation!

None really that I can think of. If you do blown in the insulation will touch the block wall which is not good.

You could add a surface layer of insulation board, then another layer of drywall, but then you might have issues with electrical outlets, door and window frames.

Re: Walls have no insulation!

Given that you are located in Arizona I'm guessing there isn't too much concern of exterior moisture penetrating the masonary block -- which would be a candiate for dense pack blown in cellulose into the wall cavities.
This would be the leat intrusive and cost effective bang for your buck.

Small holes ( no larger than 2 inch diameter ) would need to be patched.

Re: Walls have no insulation!


What if this wall has blockings?

Re: Walls have no insulation!

Two set of holes -- below and above the blocking --- are used.
However, the op stated there was a considerable gap between the exterior bock wall and the framed wall -- unless that blocking was deeper than the 2X4 it wouldn't be an issue anyway.

Re: Walls have no insulation!

Is the exterior of this wall the other side of the block? If so, would you consider covering that?

Concrete block has a lot of thermal mass, some anyway. This can be an advantage to you if it is on the inside of the insulated envelop. You could fur the outside, insulate with rigid foam and cover with your choice of siding.

The heat that gets through the outside insulation will warm up the block during the day, but not as much as it is being heated now. Then when the temperature drops at night, the heat will be released to the inside of the house. This can help cut your utility bills.

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