Tips for Installing Blown-In Wall Insulation

It is always recommended to insulate your walls. You will benefit from comfort and savings. There are materials and techniques you should  investigate before installing wall insulation. It is wise to limit to blown in insulation for an existing home, unless you have plans for renovations. Learning the facts will help you determine exactly what kind of materials and methods are best for you to use.

 Why Insulate?

If you do not insulate, you will loose heat quickly from your home. When you loose heat, you develop drafts across the floor, condensation within the wall cavity and interior surfaces, and increased heating costs. Thermal effectiveness of the wall will increase after insulating the walls. The interior surface will become warmer. The thermostat can be lowered, but it will remain a comfortable environment. Insulation minimizes sound waves and dust creating a more quiet and cleaner house. Insulating reduces the chances of mold growth which is a serious health hazard.

 Materials Needed

There are different materials used to insulate the wall. Each item has a different cost and varies in effectiveness. A few of the materials are cellulose, mineral fibers, and foam insulation. Cellulose is developed from shredded newspaper with fire retardants treated on it. It has a standard R-value and is non-toxic. It will not burn or cause corrosion of pipes or wires. Cellulose is very effective in reducing air filtration from the wall cavity. Mineral fibers such as rock wool and fiberglass are used in some walls. They require greater pressure when applying to help pack into the cavities because of catching on nails and other hang ups. Mineral fibers are best used for homes where moisture is a factor. Foam insulation is not used as much today as it has been in the past. It offers higher R-values than other materials, but problems have been caused with blown in foam.


The first step is to locate the bays in between your wall studs. Using a stud finder can assist you with this. The bay areas is where the insulation will be applied. Never fill a bay area that contains a chimney or lighting fixtures. Use a hole saw to drill into every bay on every exterior-facing wall of your house. The saw diameter should be a fraction of an inch bigger than the nozzle of the blower. Place the nozzle into each hole. Place a rag around the nozzle to make the hole air tight. When the area is filled, the machine will sound different. Have someone help you turn the machine off. After you have filled each hole, you need to patch them up using a good expanding foam sealer. When the foam is thoroughly dry, use a knife to cut the mushroom head. If the drilled holes are on the outside, replace the exterior siding. Using 2 or 3 coats of drywall compound will fill in the patches. Finally, paint the wall. Make sure you use a primer coat. Painting the walls ensure everything is covered and will make it look  like new.