Insulating An Attic
The most shared attic insulation used in residential construction will be made from fiberglass, cellulose or hydroelectricity material. You hear a lot about a term known as “R” value; which is how insulation is rated by its resistance to heat loss. The “R” value factor is 3.5 per inch of thickness. Example, a 2×4 = R11, a 2×6 = R19. Once the thickness or R factor reaches its maximum absorption rate, it ceases to be effective, consequently you need to add more insulation depending on the severity of your climate.
Precise installation increases the insulation’s R Value by over 20 percent. Neglecting penetrations in a wall in only 5 percent of a wall will reduce the complete wall’s R value by 20 percent. It will pay you both in finances and comfort to take your time and do a good job.
All walls, flooring, and ceilings should be buttoned up; however the ceiling is by far the most basic of all of the surfaces in your home. There is a simple explanation, heat rises and if not contained, will filtrate into your attic. As this happens, a negative air pressure occurs in your room then drawing exterior air from the fractures and gaps that you may have in your walls. If you only have the time, energy, and money to approach only one energy improvement, the insulation on your attic floor (ceiling) is the one to address.
The first priority is to plug the big holes and then worry about all of the little ones last. Here are several tips:
- Lay in a six inch fiberglass bat fitted firmly between each ceiling joist, then lay a six inch fiberglass bat on top going in the opposite direction. On top of these two R19 bats, blow 6 to 12 inches of loose insulation. The loose insulation will seal any penetrations that are hard to reach. Do not allow the loose insulation to cover soffit vents as you want to let hot air escape the attic in the summer and to continue the outside air temperature in the winter in order to avoid ice damming. This is snow that softens from the attic heat and collects in gutters, and then freezes causing roof damage.
- All of your electrical boxes and can lights should be sealed with tape and a silicone caulk. Look for holes in the boxes in addition as a poorly cut penetration in the ceiling.
- Attic stairs or other large penetrations are other culprits to inspect and seal.
- Inspect fur downs and other dropped-ceiling areas, along with attic kneewalls.
Once you have properly sealed your ceiling/attic floor, then start on the walls, basement and other areas of exterior exposure. “Spending time and a dime today will save dollars tomorrow.”