Known for scorching summers and mild winters, Las Vegas demands the right kind of attic insulation to keep its residents comfortable and their energy bills manageable. Insulating the attic properly reduces what the building industry calls "heat transfer"—the undesirable movement of heat in and out of our structures. We want our homes to be "thermally quiet." Of course, it's all too easy to think only of our home as the structure that's affected by heat transfer. But consider the attic a bridge between the indoors and outdoors; its insulation helps achieve the "thermally quiet" effect not just for your house but also for whatever structure the attic is part of. The most common choices for above-the-ceiling insulation in Las Vegas are fiberglass batts or blown fiberglass, cellulose, and spray foam. Fiberglass is the low-cost, widely available choice; and it works. Cellulose is eco-chic, but it, too, works. And while spray foam is pricey, it works better in some circumstances and is therefore worth discussing.
When selecting insulation for your attic, it's important to look at the R-value, which is the resistance to heat energy moving in and out of your home. In Las Vegas, our attics usually require insulation with somewhere between R-30 and R-60 (yes, that's inches). Insulation with a higher R-value usually costs more, but insulation that is too thin is not a bargain at any price; it will kill your energy efficiency and it will make your home uncomfortable in any kind of weather. A qualified insulation contractor can help you assess your current attic insulation and recommend either upgrades or complete replacement. Whatever the remedy, ensure it's done right; improper installation can almost negate the insulative effect of the material.
Selecting the appropriate insulation material and R-value is only part of the achievement of a high-performing attic. Insulation also must be installed correctly—covered completely, not compressed or gapped. Otherwise, the insulative value isn't realized, and the space functions like an unconditioned area. In addition to those basic installation parameters, we also can affect the performance of the attic by how we ventilate it, control moisture, and seal air leaks. A pro can help with that, but a pro also can help identify other potential issues that could undermine the performance of the attic enclosure. After all, a well-insulated attic is a necessary condition for an energy-efficient home like the ones we build in the Las Vegas market.
