Home Insulation & Clients
The homebuilding industry has certainly evolved in recent decades, and one of the most noticeable changes is rising expectations for energy efficiency. Environmental concerns, energy saving measures and increasingly stringent building codes are now the norm. Proper insulation is a vital part of meeting these new standards, and not just for environmental reasons. Homeowners are far more comfortable and better off financially with a properly insulated home, potentially saving thousands of dollars a year in energy costs. One of your jobs as a contractor is to alert your clients to the energy saving possibilities of going the extra mile with insulation, but to do that you need to understand the main options.
Fiberglass or Cellulose in the Attic
There are two ways to boost the insulation value of your client’s home, the easy way and the hard way. The easy way uses fiberglass or cellulose fibres blown into the attic, an approach that’s used for most home insulation improvement campaigns in Canada. It’s fast, easy, highly effective and offers an excellent financial pay-back.
You can blow insulation into walls during renovations too, but it’s not always possible because some structures don’t have the clear wall stud space required. You need completely hollow wall cavities with no existing insulation present for blowing to work.
Rigid Foam Sheets
While improving attic insulation is a great option, boosting wall insulation from the inside and outside faces is an important possibility, too. Rigid sheets of insulation suitable for use on walls come in three main types:
- Beady white rigid foam (officially called expanded polystyrene)
- Smooth textured blue or pink rigid foam (officially called extruded polystyrene)
- Rigid fiber-based sheets made of either fiberglass or rockwool
Although all three offer roughly the same insulation value of R5 per inch of thickness, the costlier extruded foam is better than the beady white expanded polystyrene because of its higher density, strength and water resistance. Applied to the inside of a wall under a new layer of drywall, or outside underneath new siding, rigid sheets have the unique and useful ability to create an unbroken, airtight layer of insulation. Even if the homeowner is planning an addition to their house and will be using batts between the new wall studs, encourage them to consider a layer of rigid insulation on the outside, too. It eliminates thermal bridging caused by wall studs, and also helps prevent internal mold growth in walls. When applying to the outside of exterior walls, it keeps internal wall cavities warmer during winter, greatly reducing the chance of condensation occurring around flaws in the vapour barrier.
Over the years spray foam insulation has gained more acceptance for residential projects, and for good reason. Spray foam, particularly the closed cell stuff, delivers amazing energy performance because it does three things better than any other insulation product:
- spray foam seals perfectly, reducing air leakage into your home
- spray foam delivers better energy performance than fiber-based insulations with the same R value
- closed cell foam solves condensation and moisture issues in cold climates because a minimum 3” of spray foam thickness acts as its own vapour barrier.
When it comes down to it, closed cell spray foam is the only reliable choice for very common insulation challenges such as basement rim joists. But as good as all this is, people are afraid of spray foam these days. I see it every time I recommend the stuff. The crazy thing is, knee-jerk fear of foam is not only unfounded, it also keeps people from enjoying more comfortable, economical homes.
Much of Canada experiences wide temperature swings from summer to winter. This gives us incentive to be leading innovators in development of insulation and air sealing innovations. For instance, water blown, high performance spray foam has been around for about 30 years. It first became available in 1986, and I first recommended it in 2005. That’s when my parents-in-law dealt with a long-standing wintertime condensation problem in an unheated attic storage area off an upstairs bedroom. Warm air would creep around the door into the storage area during cold weather, forming condensation and frost on the underside of the roof sheathing. Warm weather eventually melted this frost, causing water damage to the floor, walls and rooms below. Spray foam solved the problem by insulating and preventing condensation, turning the formerly cold space into a heated part of the house. Warm indoor air never came in contact with cold surfaces any more, no frost could form, so no water appeared. This is a classic example of what happens when you combine the ability to prevent warm indoor air and cold outdoor air from meeting, along with high insulation values. Only properly applied spray foam of the correct type can offer this combination with 100 percent reliability.