Proper attic insulation can help extend the life of your air conditioning and heating equipment, make your home more comfortable and save you money at the same time. Anything that does all that is worth a closer look!
Most often with insulation, it’s out of sight, out of mind. But don’t assume your attic – or the rest of your home – is properly insulated. Most could be a lot better, and some have serious problems.
Insulation efficiency is stated in terms of its R (resistance) value, which is a measure of its ability to resist heat flow. The higher the R-value, the better its efficiency. Remember, heat flow goes two directions: heat escapes your home in winter and enters it in summer. Attic insulation is equally important in hot and cold seasons.
Heat Transfer and Resistance
Conduction is the way heat moves through materials; insulators are poor conductors because they resist the flow of heat. For example, glass is a poor conductor, which is why windows feel cool to the touch. Thermopane windows are better insulators than single pane windows because they have two layers of glass separated by air.
Types of Insulation
Fiberglass – Fiberglass attic insulation works on the same principle, but it has thousands of fibers, each of which is a separate layer. The insulation traps air between the fibers and impedes heat flow because the air is surrounded by glass fibers. It is wonderfully efficient.
Fiberglass has been the most popular type of attic insulation since it was developed by Dow-Corning in 1938. Insulation “batts” are manufactured in different thicknesses and lengths to make for easy installation between rafters. Rolls of fiberglass insulation offer the convenience of cutting to any desired length.
Blown-in fiberglass insulation offers even more flexibility because it can be installed in any desired thickness. Installers pump tufts of fiberglass into attics quickly, with no cutting, measuring or stapling required. Fiberglass is fireproof and moisture resistant.
Cellulose – Blown-in cellulose offers the same ease of installation as blown fiberglass, including its ability to fill in easily around structural elements in an attic. It is made from recycled ground up newspaper, with dust removed and treated with a fire retardant. Cellulose provides R-values comparable to blown fiberglass, and somewhat better noise dampening because it is more dense.
Spray Foam – Urethane foam insulation is the most efficient of all. Sprayed on as a liquid, it expands to fill in even the smallest of openings, forming an airtight seal. Foam insulation has an R-value of 5-6 per inch of foam, compared to about R-value of 2-3 per inch for all types of fiberglass.
Your Attic May Need More Insulation
Many homes in North Texas have been designed to have an R-30 attic insulation rating, but we often find the actual amount in the attic falls short of that, depriving homeowners of easily available energy efficiency and cost savings. Likewise, many homeowners are deciding to add insulation to get to R-38 level or higher because of the extreme summer heat in North Texas.
While installing batts or rolled fiberglass in a new home is a pretty simple do-it-yourself project, adding blown-in or sprayed insulation is better left to the professionals. It’s dirty work that requires special tools and a bit of skill.
Got questions about attic insulation? Mascot Mechanical offers a full range of insulation services. Call us at 469-854-8667 for a free consultation and estimate, or contact us online now.