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Stacy
Insulating my home

I need to add insulation to my 53 year old masonry home. There isn't any.
I have removed the cement board and need to fur out the walls to the depth of a 2 X 4. I have learned that I cannot put fiberglass insulation on masonry due to moisture as it will ruin the insulation.
The foam type seems to be the way to go, but I am concerned about the R factor I am not getting with this product. (I can't afford to have it blown in).
Is there a product I can put over the masonry to protect the fiberglass insulation? Can you use sheet plastic?
Also, this creates another problem with the windows when I fur out the walls. I have never done anything with windows. Should I remove them and re-frame the inside. What is the best wood to use for a new sill. The one that is there is marble.

canuk
Re: Insulating my home

Stacy ... good stuff on the plan for the insulating of your home.:)

Quote:

I have removed the cement board and need to fur out the walls to the depth of a 2 X 4.

The foam type seems to be the way to go, but I am concerned about the R factor I am not getting with this product. (I can't afford to have it blown in).

I'm not clear on the cement board ... is this the interior wall board and the need to fir out 3 1/2 inches ?

Also it's unclear about the concern regarding lack of R value with foam ?

Stacy
Re: Insulating my home

Yes, interior wall board. Behind that is just 1/2" boards that are nailed to the block and the wall board was nailed to that.

The styrafoam type insulation doesn't seem to have as high of an "R" value compared to a fiberglass insulation. I would like to try and do the best insulating job I can the first time.

canuk
Re: Insulating my home

Stacy .... thanks for the clarification.

If you have the interior walls removed then installing any type of insulation should easily done.

You may be able to place 2x4 framed walls fastened to the floor and to the ceiling rafters..... then have the insulation installed.

I'm not sure what foam insulation you are looking at which wouldn't have as much or better R value per inch compared to fiberglass.
The 2 lb. closed cell foam would have equal or better R value with the added benefit of not needing a vapor barrier and would be resistant to any potential moisture issues from the brick exterior.

Since the interior walls are open the foam could be easily sprayed in place before applying the finish walls.

If the spray foam is not affordable then you may consider using sheets of rigid foam insulation applied over the existing furring strips. Use a house wrap tape to cover all the seams which provides an airtight seal.
This will completely cover the exterior walls providing a continious thermo barrier.
Then put up the framed walls in front of the foam. If you wish add fiberglass for extra insulation.
Having the continious thermobreak behind the studs with improve the insulating performance.

Hope this helps. :)

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