Three years ago I bought a 1949 brick Cape Cod with thick plaster exterior walls. The exterior walls look like drywall, but are much thicker with plaster. Someone told me that the walls are made of what oldtimers call "greenboard". The problem is that the first floor is very cold and drafty, particularly the rooms facing north. There is as much as a 10 degree difference between the thermostat and my young son's room and on cold nights we have him sleep upstairs.

I want to insulate and am thinking of blown in insulation and doing it myself. Can I do this myself, or with help, and does this stuff also act as a vapor barrier? Will it cause a moisture problem with the brick, since I have heard that brick needs room to breathe?

I am also looking at using a do-it-yourself slow rise foam kit at R-7 per inch, E-84 fire rating, and an expansion ratio of 8:1. It's pretty expensive at $650 for a a kit covering 605 sq. ft. 1" thick, but seem as if it would do a better job.

Any comments would be appreciated.

 

Brick houses built then were veneer. Furthermore, brick veneer has a drainage plane between the wood framing and the brick. This means that the stud wall is not in direct contact with it.

Blowing in insulation or injecting foam may be a do-it-yourself task, but you have to be fairly handy, especially with the foam. The expansion of the foam may crack you plaster walls. In either blown in or injection you do want to compare cost for doing it yourself or having someone do it for you. In some cases you might find it is not that much difference for having someone blow in the insulation. Especially when you consider, renting the equipment, what you will pay for the materials and taking the time off to do it.

Because of the brick veneer, the do-it-yourselfer cannot do it from the outside of the house, which means you have to do it from inside.

 

The foam is a slow expansion type for retrofits so it won't blow out the walls, however, it looks like the best "bang for my buck" would be the blown in cellulose insulation. Since I can't install a vapor barrier, will the cellulose help reduce vapor? Also, how well will it protect against drafts?

 

Your want a contractor that uses dense packing technique when blowing in cellulose insulation. This will effectively reduce drafts. The several layers of paint on the walls qualify as a vapor barrier.