Putting Insulation In Old Walls

Unfortunately however builders didn t insulate the walls of most homes built before the 1980s.

Putting insulation in old walls.

Rigid boards work best on exterior walls along with a vapor barrier. Before switching to spray foam insulation tom used to use polyisocyanurate panels that way he would build a 2x4 wall insulate between the studs with batting paper face removed then cover the whole thing with foil faced panels and seal them with foil tape before putting up wall board. Walls both exterior and interior are the next area to insulate in a home. The r value of the batt measures the thermal resistance so the higher the r value the more effectively.

Most communities have building codes that require a minimum amount of insulation in a house s exterior walls and ceiling. When considering new insulation installation or home retrofit insulation many dc area homeowners wonder if it s necessary to remove the old insulation first. Your walls in their present state have an r rating of about 3. You can often leave old insulation.

The answer in many cases is yes. The walls have the original lath and plaster with 1 2 drywall over that. I m doing a small remodel on a 100 year old home to use as rental property. In a perfect world you would be able to unscrew invisible bolts remove drywall panels install insulation and reinstall the panels our less than perfect world of permanently attached wallboard means time consuming hacking away of gypsum individually removing drywall screws or nails installing r 13 or greater fiberglass roll insulation and re installing the drywall.

I m not a big fan of blowing in insulation from the outside. Fiberglass batts foam or cellulose can be used to insulate the interior walls. According to the international energy conservation code iecc for your area mass walls ones made of thick block brick stone or adobe should be at least r 10. So can you put new insulation on top of old insulation.

I really don t want to tear all that out and open the walls. The third area that needs proper insulation is the floors. Insulating interior walls isn. There is zero insulation in the walls.

Can you simply add new insulation on top. Choose fiberglass insulation batting. The advantages of insulating interior walls. Adding 2 inch thick insofast panels will bring your walls to r 13 30 percent more than the iecc minimum.

There are various grades of insulating batting for different locations in the house so you ll need a different insulation for interior exterior attic or basement walls.