Insulation is an essential part of any energy-efficient home. It helps to slow down and reduce heat transfer, and by sealing air leaks and adding the right insulation to the attic, tight spaces, and basement, homeowners can save an average of 15 percent on heating and cooling costs, according to the U. S. Environmental Protection Agency's ENERGY STAR Program.
When it comes to insulation materials, there are a few different options available. The most common are fiberglass, foam, and cellulose. Fiberglass is one of the most affordable types of insulation and is easy to install since it comes in blocks, loose fillers, rigid foams, and spray foam that fit the standard width between wall posts, attic beams, and floor joists. Foam insulation seals leaks and gaps within existing walls with liquid polyurethane that expands and hardens into a solid foam.
For larger areas, homeowners can use a foam insulator sprayed under pressure (foamed on site). Blow insulation is applied with a machine that blows a paper-like material into the space to be insulated. This type of insulation is usually made of fiberglass, rock wool, or recycled cellulose material (such as recycled newspapers or cardboard). Rock wool, or mineral wool made from extruded lava rock, is an excellent insulating material for typical wood-framed residential structures.
It insulates against heat transfer and sound, and is resistant to fire and moisture. Rock wool is more expensive than fiberglass but just as easy to install. It usually comes in rolls of blocks in pre-cut widths for easy installation. Closed-cell spray foam insulation is the most energy efficient wall insulation with R values up to R-6.2 per square inch (approximately R-34 on a 2 × 6 wall).
It's important to remember that some insulators can irritate the skin and respiratory tract and can cause other health problems. For this reason, adequate ventilation, personal protective equipment for the eyes, hands, skin, and respiratory tract, and safe installation procedures are absolutely necessary when working with different types of insulation materials.