Warm air naturally has a tendency to move to cooler regions. Attic is the place where this heat exchange between the inside air and outside air takes place. In the absence of proper insulation, the warm air leaks outside the house in the cooler climate, whereas the hot outside air enters the house on warm days.
This heat exchange can put tremendous stress on your central air conditioning system and in turn consumes a lot of energy. A good solution to this problem would be to insulate the attic.
Often, attic is the farthest place from the central air conditioning system. Hence, it is hotter than the rest of the house. Insulating attic can control the extreme temperature in the attic and make it a comfortable place.
How to Calculate the Cost of Insulating an Attic
Loose fill fiberglass is the cheapest insulating material. It is also the most commonly used insulating material for the homes. Other materials include cellulose and mineral wool. Cellulose is the most eco-friendly option and provides high thermal and acoustical insulation.
Batts/roll insulation is slightly more expensive than loose fill and comes in materials such as fiberglass, rock wool and cellulose. If you are planning to go for loose fill insulation, then you will need a professional to complete the task. Average sized attic insulation costs about USD 700 - USD 1900 for this type of insulation.
R-value or the resistance of the material is another factor that influences the cost of an attic insulation. The more the R value of the material, the more its effectiveness at insulating. Cost of insulation increases with the increase in the R value. Attics as well as high rise ceilings such as those of cathedrals demand higher R value than walls.
If you hire a contractor to insulate an open attic to modern standards, you are likely to spend USD 1.40 - USD 3.60 per sq ft. However, the desired R value and the local climate are likely to affect this cost. Thus, for a 800 sq ft space you will be expected to shell between USD 1120 - USD 2880.
If you are going to do the attic insulation, roll out batting is your only option. In that case, you will most likely spend about USD 500 - USD 1000. Again, attic size, R value, cost of materials in your area, etc. are bound to affect the actual cost.
Blow insulation for filling the loose fill material into the roof, ceiling or walls of attic can be done with a professional help only. In that case, cost per square foot would be about USD 2 - USD 3.50. Thus, the rough estimate for insulating a 1000 sq ft area by this method is about USD 2000 - USD 3500.
Before you go for an insulation job, always weatherize your home. Check for leakages through the attics, else your insulation efforts would be entirely a waste. Go through the guidelines published by the US Department of Energy for safe and efficient insulation of your home.
Always assign an insulation job to a reputed utility company and do ask for referrals for contractors. Some utility companies may offer discount on home insulation during certain time of year.
To get an accurate estimate on attic insulation, you may use an online calculator available on some websites. You can get the correct estimate according to the parameters submitted by you.