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Brick house 2x4 walls, no insulation

We have a brick home built in the 50s. It has 2x4 walls and no insulation. I have read all the debates regarding insulating the existing walls. So here is where I need help. Could I build 2x4 walls over the existing plaster and insulate them and then cover them with drywall? What would be the steps? Vapor barrier? There is none in the cavity now. The house is on a slab. I live in northern Indiana where it is cold and windy in the winter. The exterior walls are very cold to the touch. I have insulated the attic.
Thanks for any help you can give!

MLB Construction
Re: Brick house 2x4 walls, no insulation

your plan doesn't make sense to me. it seems like it would be a lot of extra work to do your plan.

how about.....
1. have a company blow insulation into the existing walls
2. strip your existing walls, insulate then put up new walls
3. strip your existing walls, have spray foam insulation installed then put up new walls

according to your plan, installing walls in front of existing walls would result in a decrease of 4 sq ft of space per 12 linear feet of wall. that's about 15 sq ft of space per room (on average). plus all the electric would have to be extended out to the new wall. what about baseboard heat or radiators.

don't micky mouse it....do it right

Re: Brick house 2x4 walls, no insulation

I agree with MLB, but if the house was built in the 50's, it should have some insulation. Typically houses of this era had 2.75" fiberglass with an R value of around 7. Why do you think it has no insulation? You would need to knock a hole in the plaster to be sure.

If it turns out to actually have R7 fiberglass or rockwool, the cost to upgrade would actually never be recovered, at least not in your lifetime. Even if the walls are empty, they still have an R5 just due to the air space and the different layers of materials. By comparison, an uninsulated ceiling with a conventional attic has an R value of around 1 because it doesn't have the trapped air that a wall has.

You will actually get a better return on investment (ROI) by upgrading your windows and doors. Generally you can do the windows for about the same money as tearing out the plaster, insulating and then new sheet rock. A small investment in weatherstripping has one of the best ROI's.

You should not undertake any insulation project without an energy audit from your local utility first. If you can get your house scanned with an IR camera, that would even be better, otherwise you are just standing in the dark throwing money around and hoping that it does some good. It is better to pinpoint and prioritize your heat losses so that your investments pay off for you.

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