Tuesday, December 9, 2008

How we left a window open thru three Vermont winters (or why you might need a professional home energy audit)

Getting a home energy audit helps heal the planet, saves money, and makes for a more pleasant home. Everybody wins.

President-elect Obama understands the importance of efficiency, and so part of the economic stimulus package is to insulate all public buildings.

But let me tell you about that window. A few years ago, I decided to make our property as green as possible. First, I wanted to get solar panels. But the solar experts that I talked to said that the place to start is getting an energy audit, because you can save more energy faster and cheaper this way.

So I called in an expert in energy efficiency for a consultation. Bill Calfee, of Peak Energy Solutions, in Dorset, Vermont came by to do the energy audit. We walked through the house. Opening a closet in the guest room, we stood underneath the hole in the ceiling to the attic. There wasn’t a cover over the hole to the attic. “Well, here’s a big thing,” he said. “This is some of that easy-to-fix, low-hanging fruit that I mentioned. The money you’ll save by fixing this will make up for the cost of the audit many times over.”

See, the unheated attic is normally the same temperature as outdoors. Yet because there was no hole cover, the warm air was rising into the attic and cold air was descending. We had the equivalent of an open window to the outside. No wonder the house always felt drafty!

Calfee pointed to the black dust and grit attached to the pink insulation that had accumulated on the side of the hole. He said this was the residue of passing air, signifying lots of air passing through this space. “D’oh!” I said. Apparently, the house builders had only covered the hole with a piece of plywood. Somehow it had been gotten pushed aside and left uncovered. We think it had been that way for years. The closet door was often closed, so it wasn’t quite a wide-open window, or we might have noticed earlier. But that room was always cold. The next day somebody came and built a thick, foam-board insulated cap for the hole, and now it’s tight as a drum up there.

So I tell this story to illustrate why home energy audits are important. Experts can see things other people wouldn’t see. Sometimes you have to call in the pros. Additionally, the pros have a few superhero tools for sussing out a home’s efficiency. They have the blower door and the thermal camera!

Calfee brought a sort-of hand-held video camera that measured heat and cold. Pointing to the plastered over walls, the camera showed where the house builders hadn’t brought the pink roll insulation all the way to the top of the bay between the joists. By leaving just 2 inches uncovered, it was creating a steady heat lose. Pointing to the laundry room, he showed a section that somehow didn’t get insulated at all. The camera showed small cracks in the foundation that were easily filled. Everywhere that cold air was rushing in was made visible and so we could deal with it.

Next Calfee used “the blower door” to measure how airtight the house is. The blower door is a strong fan attached to a laptop computer, with a plastic sheet that fits snug over a door frame. You shut every window, door, and vent in the house. Then you turn on the blower full speed for five minutes. Then you turn it off and the computer measures the fan’ activity. Is it spinning backwards? How fast? By pressurizing the house in this way, we could see how airtight the house was.

Very useful information. It turns out though our house was only ten years old, it was pretty leaky. Recently, they did the blower door again, and now the house is tight. Getting this house to be energy efficient feels like a victory to me. It took almost two years, numerous calls to plumber, carpenters, and insulators, but now the house really is efficient and warm and green.

Here’s a short summary of what we ended up doing. We had a foot of cellulose insulation sprayed into attic to insulate the ceiling thoroughly. Fixed the cracks in the basement foundation. Made holes in the walls and blew in extra cellulose insulation. In the basement, we had a foam sprayed over the concrete walls, because concrete has an “R-value of 1” (or insulating ability of a single pane of glass.) The walls were sprayed with this gooey, soy-based foam, which hardens into a layer of insulation that looks like the surface of lemon meringue pie.

In the big picture, energy efficiency is one of the most important places where our society can start dealing with the environmental crisis. Every watt of energy that we save is one that Vermont Yankee doesn’t have to toxically produce. A tight house burns less oil and thus less carbon. Energy expert Amory Lovins of the Rocky Mountain Institute says that saving energy should be a huge part of our national energy plan. He calls saved energy “negawatts.”

Eventually we did get a pretty cool solar system. Forty percent of the homes HEAT is generated by the sun. We put in a big solar system that heats water that runs underneath the floors as radiant floor heating. Eighty blue vacuum-tube solar panels gather the sun’s heat, which warms tubes of the antifreeze liquid propylene glycol, and then circulates down into the basement to a 500 gallon water tank that stores the heat, and then it flows through tubes under the floors as radiant floor heating. This is a beautiful way to heat a home. The floors are warm to the feet. The energy is free and burns zero carbon. As we strive to create a zero-carbon world, solar heating systems should have a place of honor. We estimate this solar system will pay for itself with savings on oil bills over 10 years.

A real estate agent told me that everyone says that their home is tight but most houses aren’t. Creating a super insulated house could be a priority if you are building a new home, but it probably won’t be unless you plan for it. Construction workers are often more concerned with getting a job finished than creating a house that has long-term low heating costs. Efficiency and green building techniques should be ”the new normal”, but they aren’t yet.

I strongly encourage everybody get an energy audit and to deep insulate their homes. It saves money and energy. It’s a good investment if you own the house, because you’ll pay lower fuel bills in the long run. Additionally, houses with green credentials are a lone hot spot in the housing market, according to a recent article in the Wall Street Journal. And the house is just nicer to live in. After the truck came and blew lots of cellulose insulation all through the walls and the attic, it was like a giant blanket had been placed over the house. Investing in good insulation is smart for the energy bills, the earth, and for our feet.

More info is online at www.efficiencyvermont.com. and www.serg-info.org and www.energy-wise-homes.com.

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