Keith inspected this 24 year old home in Augusta. It was a 1900 sq. ft. home. The federal recommended air leakage for this home to maintain healthy breathing is 1590 CFM. After doing the door blower test Keith determined the home leaks 3780 CFM’s, or 2.5 times more than it should. Now this home has all new windows and doors so the living space is pretty tight, we found that most of the leakage was in the attic. As you can see in the photo the fiberglass measures an R 30. However, that is not the “effective” R value. Most manufacturers test their insulation in a perfect air tight wall panel inside a lab. Once that fiberglass is laid in an open space it loses almost half of its R value. It has gaps on all sides and is laid loosely, and air is washing over and through it.
By blowing a solid layer of cellulose over the fiberglass we can build the R value up to the recommended rate of 60. We will build some plywood dams around the scuttle and chimney so we can blow insulation right up to them. We will need to extend the proper vents and add a fire stop to the chimney. How much of a return? Oh just about $37,000 in 20 years! What could you do if that money got freed up for you?
Yesterday, Keith inspected a home in Hampden that is an early 1800’s home; the homeowners are concerned about inferior insulation. The homeowners are spending $600 a month to heat the home. That is a lot of money for a small home. Nothing is insulated on this home.
So, where to start? Keith explained to the homeowner about the ABC’s of insulating your home. First priority or the ‘A’ is always the attic, because that is where all the heat goes and leaks out. Second priority is the ‘B’ or basement, which is because the basement is where all the cold air is sucked in to replace the air above leaking out and the combustion furnace needs that new air to run. The last place to spend money on insulating and windows is the main floor, or the ‘C’ conditioned space. Why? Because that is the neutral plane of the pressure battle going on inside all homes. It is also where you get the least return on your money. So, if you’re on a budget tackle your attic and basement first to get the best return on your investment.
The homeowner in Bangor, Maine told us that this new $400,000 condo was so hot inside during the spring and summer it was unbearable to live in. As you can see from the pictures, it only had R25. It had no air sealing, and many pipes and vents were exposed. The attic also had a lack of ventilation even though it had ridge and soffit vents. The minimum amount of ventilation is 150 sq. ft. per 1000 sq. ft. of attic space, but we prefer 300 sq. ft. as a rule of thumb. By raising the insulation to R60, installing an insulated cover over the stairs, and installing 3 roof vents we can eliminate the heat from radiating down into the home and make the home much more comfortable for living. It also will cut the electric bill by 30%! This Bangor, Maine homeowner is spending $300 a month in the summer to cool the home. We could also install foil radiant barrier in the attic to reflect the heat back to the roof. It is against code to put insulation up tight to the chimney; also this chimney has no fire blocking. Without it, this just enhances the stack effect. 2″ thick Rockwool board or Thermax up against the chimney would solve both the fire block, and allow you to blow insulation up tight to the chimney. Hard to believe this is a new home.