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Putting the insulation cart before the horse

As I yanked and grabbed and ripped sheet rock off the north wall of this house, I thought back to when I had installed that very sheet rock, about 34 winters ago. We moved this house in, and, believing that gutting it and reinsulating it to modern standards, we'd be warm and cozy and assured that we were as efficient as we could be.

Uh uh. That was not the case. Despite installing foil-faced fiberglass insulation in the walls, and conscientiously stapling it to the joists so it would be air tight, such was so not the case.

Insulation does absolutely no good if there is any air movement through it at all, even the slightest, like where the wall meets the basement, where outlets are installed, where electric wires pass through up and down, where windows are framed in, where, where, where. There are a thousand wheres in the construction of a framed house. This house, it turned out, had just about all of them, despite our attention to insulation detail.

The window rough-in framing--between the window itself and the wall surrounding it--was caulked with fiberglass batting, which doesn't stop air at all. The outlets seemed, during cold weather, to have little fans inside them, blowing cold air in. When the wind blew from the north, we lived on the south side. From the east, the west.

After several winters, we had a blower door test done. This involves a powerful fan mounted in the doorway, which sucks air out of the house, allowing one to walk around and find where air is blasting in. The main culprit was where the house framing met the concrete basement wall.

That was sealed with foil-faced urethane board, a process that took about 20 man hours. The difference was unbelievable. In this article, I am going to recommend a couple of actions. A blower door test is one of them. It is simple, and the infiltration leaks that it points out are usually relatively easy to correct. Our heating bill dropped nearly in half.

About eight years ago, the process of urethane foaming open walls became fairly popular. I started with the upstairs in this two-story farm house, doing one, maybe two rooms each year. As I adjusted my dust mask and pulled the foil-faced insulation from the stud cavity in the wall, I realized that I was almost done. These were the last two rooms to gut, urethane foam, resheetrock and tape, and paint. The entire house will be finished.

To give you an idea of how much air blows into a frame wall, I merely have to point to the half a coffee can of driveway grit that fell out of the insulation as I stripped it from those outside walls that faced north, faced the driveway. It was unbelievable how much air over the last 30-odd years must have moved into these walls. That was air that I paid to heat.

There is a term for this infiltration air leakage: It is called air change, or better yet, air changes, plural, because the air in a house changes each hour. New houses, where extreme attention to detail is applied, leak about 12 percent of their entire contents each hour. Old houses? Up to 60 percent. That means, if it is below zero outside, you have to pay to warm that air up each hour. Most of your fuel bill in a house goes to this infiltration process. Even worse, the more leakage there is, the worse your insulation is doing.

New houses, foamed with urethane insulation, leak less than six percent. So, here is the second recommendation: Are you building new? Insulate with urethane foam.

As I finished bagging the dusty insulation, a nasty process, I thought about how much we've learned in a very short time about energy consumption, and about how much we're going to learn in the very near future.

That thinking leads me to believe that we have put the cart before the horse in our approach to all this. Such thinking is not news. Mankind usually manages to get most large decisions bass-ackwards. Why should this one be any different.

There are two components of the energy situation that are affecting us: How tight our houses are, and how we are heating them. We've come just about to the end of how we are heating them. All the improvements have been made. Gas furnaces are up to if not past 95 percent efficiency. They cannot go any further.

Air source heat pumps too are approaching new levels of ability to move heat from the outside air into the home. We have almost reached their maximum ability to do so. The bottom line? That's it, folks, for this end of those two very important focus points. It isn't going to improve significantly, not any more

That means, if you've thrown a ton of money into your mechanical systems, they are going to cost you more and more each year, as we see electrical and fossil fuel costs skyrocket. This approach is over. Done. Whatever you've done with this approach is going to cost you more and more and more each ensuing year.

That's the cart. The horse is insulation and tightening, which is, I am thinking as I stuff the last dusty batt of insulation into a garbage bag, what we should have been doing all along, instead of taking the easy but also expensive approach of putting in a more efficient heating system.

If you spend money today on insulation, it never breaks down, no one charges you more for using it. In fact, it continues to faithfully repay you each year.

If your heating costs were a thousand dollars this year, there's a very good chance they will be two thousand inside of five years. No matter what you do to your heating system, the cost of operating it will continue to go up. Unless you insulate.

A blower door test, some plugging of leaks, some redoing of outside walls: Those things will never cost you again.

We got the cart ahead of the horse. Hang on to your wallets. This is not going to turn out to be a smooth ride.