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anyway 07-11-2010 08:54 PM

insulate perimeter of the foundation
Hi, we live in Canada, my wife, which is from south America, has owned a house that has a fully nicely finished 2 bedroom basement that has no insulation.

The basement was finished a few years ago by some people who didnít bother or didnít know that insulation was needed.

The only thing that is between the foundation wall and the sheetrock, is a vapor barrier and a one inch thick board. Absolutely no room for blown in insulation.

We must insulate the perimeter of the foundation. I notice that the new houses around here must have the perimeter of the foundation insulated with a 2 inch thick blue Styrofoam.

I was thinking digging the perimeter to the bottom of the foundation, and put 2 layers of the same type of Styrofoam to insulate the foundation.
I would like to know what they use to fix and seal the Styrofoam to the foundation.

Perry525 07-22-2010 11:54 AM

insulating a basement.
The thing to be aware of is:
Heat always moves to cold!

Therefore, if you place the insulation on the outside of the basement, to keep the rooms warm, you have to heat the air in the rooms and the walls, ceilings and floors. As this structures will absorb an enormous amount of heat, before you feel warm.

The thing to do is place the insulation on the inside, so that you have a layer of sheet rock, then the vapor barrier, the insulation and the wall.

The same applies to the ceiling, sheet rock, vapor barrier, insulation, joists, floorboards.

And the floor, floorboards, vapor barrier, joists, insulation between the joists and under the joists.
Or floorboards, vapor barrier, insulation, concrete floor.

In most homes the largest loss of heat is through gaps, cracks and holes, when you join all the vapor barriers together, to create a sealed air tight box, this will make a very large difference to your heating bills, the insulation will help.

You will then need to install a controllable ventilation system, to get rid of stale damp air and to bring in fresh air, an extractor fan with a built in heat exchanger will solve this problem

nealtw 12-30-2010 05:22 PM

Sometimes when a house is built on poor soil will do a pan slab foundation. footings foundation and floor all in one poor. In tha case the use 2"foam outside the foundation
The top is covered with a metal flashing from under the siding. I don't know what happens to the rules about exsposed concrete when they do this,but they do it on new houses and it passes.

shoothebunnies 12-30-2010 09:51 PM

have you looked into the spray foam insulation?

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