It's a well-known fact that walls are an important source of heat loss.
As a result, the better you insulate your building envelope, the more you will be able to invest, in the medium term, on something else than house repairs – your RSPs, for example!
Actually, an insulation product such as sprayed urethane foam makes it possible to save on your house structure (e.g., by using 2 x 4s rather than 2 x 6s).
All in all, far from being a luxury, wall insulation is actually a necessity!
Advice from Isolation Majeau
Many different materials can be used to build walls, and several products can be used to insulate them. A few guidelines for wall insulation:
Same as for all insulation products, the vapour barrier must comply with the insulation regulations of the Québec Construction Code (2005).
Tip: Insulate adjoining walls as you would for a separate cottage, and pay special attention to walls made of cement blocks (town houses).
Although very popular, fiberglass batts is not the only material you can use to insulate walls:
It is not uncommon to find insulation deficiencies in end joists. Conventional insulation should be avoided in these areas because of the nearby concrete and the high risk of air infiltration.
Insulating an end joist is particularly challenging because of its shape. The application of 3.5 inches of sprayed urethane foam ensures a hermetic seal, and therefore continuity with the insulation of the foundation and the walls.