How to Insulate Your Atticby Marcus Keilch on 04/23/13
Whatever type of climate you live in, it's hard to stay comfortable and keep your energy bills manageable if you don't have adequate insulation in your attic. But most home owners don't know how much they actually need. The answer is dependent upon where you live. It is generally recommended that homes in a warm climate should have insulation with an R-38 rating, while homes in cold climates need insulation with an R-49 rating. These insulation levels will keep heated air from escaping during the winter.
Today there are a variety of attic insulations to choose from. Some insulation materials are better for warm climates while others are better for a cool climate. Two types of attic insulation that work in similar ways are rolled insulation and blown in insulation. Rolled insulation is more expensive than blown in insulation, but is easier to work with because it is laid down piece by piece. Rolled insulation is usually made of fiberglass, but is also available in cotton fiber as well. The advantage to using rolled insulation is that it is faster and easier to work with. Blown in insulation is also fast and inexpensive, but it is better installed by a professional contractor with a blowing machine made specifically for this purpose. In addition, it seals air spaces in the attic better than rolled insulation. Blown in insulation can be made of Fiberglas or cellulose, though Fiberglas is usually less costly than cellulose.
For insulation to be effective it must be the correct type and have adequate thermal resistance for the home’s location. The capability of any material to slow the movement of heat is referred to as its thermal resistance or R-value. Insulation materials are rated based on their R-value. The higher the R-value, the longer it takes for heat to move through the insulation. However, it must be properly installed. Building codes specify the minimum amount of insulation necessary and the installation guidelines.
Either rolled or blown in insulation is appropriate for a warm climate. The most important factor for insulation to be effective in a warm climate is the addition of a radiant barrier to whatever type of insulation is used. The radiant barrier is not a substitute for traditional rolled or blown in insulation, but it will work together along with traditional attic insulation to make your home more comfortable and energy efficient.
In a warm climate, the addition of a radiant barrier can bring an energy savings of 30% or more.
A radiant barrier is a type of reflective foil that is placed between the attic floor and the insulation. The barrier foil effectively blocks heat during hot weather while keeping heat in during cold weather, to cut energy usage all year long. Some brands of radiant foil are available with perforations, which allow moisture to escape in order to avoid mold and mildew problems. Adding a radiant barrier is similar to using a car sunshade that blocks the heat and reflects the sun to reduce the temperature. A radiant barrier is also helpful in cold climates, as it reduces radiant heat loss, similar to wrapping hot food in foil to keep it warm. That way the food does not emit as much radiant heat. Combining good attic insulation along with a radiant barrier will give the best energy efficiency.
The new comer to the field of attic insulation is Spray Polyurethane Foam Insulation. It can be used in one of two ways to insulate your attic space and protect your home. Some roofing contractors prefer to use it in the traditional place, the attic floor. The spray foam is used where traditional rolled insulation is used, between the floor joists. Other contractors prefer applying spray foam directly to the underside of the roof deck, which insulates the entire attic space.
A qualified roofing contractor can guide you in choosing the best way to insulate your attic. To find a reputable contractor, look for someone who is licensed, bonded, and insured. Ask how long they have been in business in this area, and if they can provide referrals from satisfied customers. Check with the Better Business Bureau to see if there are unresolved complaints lodged against them.
Heating and cooling costs account for 50 to 70% of the average home energy usage. Insulation is an investment that quickly pays for itself. The costs to purchase and install insulation are usually recouped in just a few years, while keeping your home more comfortable and adding to its value.
Written By Jason Swim
24008 N. 104th Avenue
Peoria, Arizona 85383