Wall Cavity InsulationMost of us are continually looking for ways to save money on our home energy bills.  Now that winter is upon us, everyone is feeling the impact.  This is an interesting article related to effective ways to cut energy costs.  It explains a typical problem with older houses and how spray polyurethane foam (or SPF) can easily resolve it.

Cavity insulation is probably one of the easiest and most cost effective ways to lower your home heating (or cooling) costs and to reduce your carbon footprint. While newer construction methods require the use of insulation during building, older homes and buildings, especially those of brick or masonry, can contain little other than the dead air space between the walls. This is the ‘cavity’. It needs to be filled.

During the 1920′s, builders of masonry and brick homes changed techniques in building exterior walls. What used to be single-wall construction progressed to the use of a double-wall configuration, with those walls close together and separated by a dead air space. This made the wall sturdier and stronger. Unfortunately, air isn’t the best insulator and this type of construction is not very energy efficient in preventing heat loss through the walls.

In later years, it was learned that filling this air gap (or cavity) with an appropriate insulating material would improve the wall’s energy efficiency. One popular method for filling this void was by introducing small, plastic pellets through holes drilled into the building’s exterior surface. The pellets would settle and fill up the space, adding a noticeable degree of insulating properties to the wall.

Since this double-wall construction was only used for exterior walls, accessing the surface needing attention is usually simple. It’s on the outside of the building and easy to get to. This makes the job of retro-insulation fairly straightforward and unobtrusive for the inside occupants. And it’s a quick job to complete also.

Technological advancements have made the ‘greening’ of your home easy and cost-effective. Weather proofing a home not only makes it more efficient but also more comfortable. It’s estimated that 60% of your home heating costs would be saved if you insulated your old, double-walls. It’s inexpensive to do and will end up paying for itself in a very short time.

The most up to date and efficient way to insulate brick or masonry walls is to use expanding spray foam. This liquid, which contains special polymers and a foaming agent, is simply sprayed into small holes drilled into the exterior walls. Once in the void, the foam expands, dries and hardens. This takes only a matter of minutes. One advantage of using spray foam is that when it expands it fills every nook and cranny in the cavity, forming an air-tight barrier.

By using foam for your cavity insulation you’ll not only prevent heat loss in winter but also have a cooler house in summer. Noise levels will also be reduced. Your house will be more comfortable and your heating costs will be lower. All this, and the job ‘pays for itself’ in a few years, after which it’s ALL savings. It’s a good deal.

4 Responses to Insulating wall cavities with expanding spray foam

  1. Nicholas Katalifos

    You should never NEVER insulate the space between brick veneer and wood sheeting. Moisture can build up and corrosion occurs. The damage that can be caused far out-way the supposed benefits!!!

  2. doug

    shoud you foam between block and brick wall it has a air space of 2in some one drilled holes and foamed only the top 5 rows ob rick and i am wondering way i have bricks that are faling apart in those area and some below

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