insulation

My name is not Earl. I’ve crossed everything off my list, and I’d like to share what I have learned about home weatherization.

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I’ll start with my results to date. I spent roughly $400 and achieved a 60 percent reduction in my gas-heating bill for the month of February. That huge reduction is testimony to what an energy hog my house was before I started this project.

My goal is an 80 percent reduction but that last 20 percent isn’t going to come easy. To obtain that I will need to install a solar hot water panel in the one sunny patch of yard I have, a heat exchanger on the first floor shower drain, and possibly one of these bad-boy heat pumps. Our hot water accounts for almost 20 percent of our gas use.

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Here’s my list of weatherized add-ons:

  • Reroute gas-furnace-air-intake ducts to draw warm air from heated space rather than basement.
  • Install R-21 insulation in unheated basement ceiling (which is the floor of the first story).
  • Design and build moveable pop-in insulated shutters for all first floor windows.
  • Keep upstairs doors to bedrooms and bath closed during day.
  • Install R-11 in stairwell wall that leads from unheated basement.
  • Weather-strip door from basement to house.
  • Install insulated door on laundry chute.
  • Install insulated damper in fireplace.

We maintain the first floor of the house (where the thermostat is located) at 70 degrees during the day (when occupied) and at 60 degrees during the night or when unoccupied. The heat loss from the first floor keeps the upstairs warmer than 60 degrees. As you walk from the balcony to the second floor, to the first floor, and into the basement you can feel the air get colder and colder because warm air stratifies (hot air rises).

We use encapsulated fiberglass insulation battens. The fiberglass is enclosed and won’t get under your shirt and make you itch like a man on a fuzzy tree (uh huh). It is usually white and reflects light well. It costs more, but it is not the fire hazard that paper-backed insulation can be. Building codes require that you cover paper-backed and foam-board wall insulation with a 15-minute fire barrier (typically gypsum board or metal) to give occupants time to escape a fire before the smoke and fumes are released.

The most effective item on the list by far is the pop-in moveable insulation. In theory, these things cut the heat loss through our walls almost in half. We have a lot of big windows. You should be thinking, “What in the hell is pop-in moveable insulation?” It’s a piece of insulation cut to the shape of your window and covered in cloth that you can “pop” into the window cavity from the inside. Get it?

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How to make your own moveable insulation:

  • Use two-inch thick polyisocyanurate insulation board with aluminum foil on one side.
  • Use a cheap sabre saw to cut the foam about a quarter of an inch smaller than the opening you plan to cover.
  • Cover the edges with God’s gift to man (duct tape) to keep them from chipping.
  • Use sticky-backed foam insulation strips to fill gaps around the edges. It does not have to be perfect.
  • Sew or have someone sew a cover out of fire resistant fabric. Be sure to add a few tabs to make handling easier.
  • Install it with the foil toward the inside of the house leaving a gap between the foam and the glass.

Make one for a single window to get up the learning curve before you move on to another window. Each window will be different and will require a different design.

Watch for signs of excess moisture against the wood sill. My windows stay dry, but if yours don’t, you can protect the wood with a few extra coats of oil-based paint or a good sealant. Tile or slate also works if you have nothing better to do.

Back in the ’70s when America was first introduced to the concept of energy conservation, insulated window shades were all the rage. They are a form of moveable insulation, sometimes referred to as night insulation. They could boost your window up to around R-4 or 5. The ones I made take the windows to around R-12.

I was granted permission for this experiment from my family under the condition that the insulation does not go up until after dark and is out before my wife gets out of bed. For all of you wannabe handymen out there, always remember, “Ain’t mama happy, ain’t nobody happy,” and “If the women don’t find you handsome, may they at least find you handy.”

Keep in mind while designing these what you will do with them when they are not in the window. They can fold accordion style and lay behind a couch. They can be covered with art and hang on the wall in plain sight, even on top of each other for a 3-D look. If you have a artist-friend, turn her loose on them. They can be beautiful, high-status works of art — conversation pieces at dinner parties.

Every house is different. The highest priority and the biggest bang for your buck is to insulate your attic or roof. The best insulation is fiberglass and the more, the better. Be careful not to block airflow from the eve vents. I already have R-36 in mine.

The easiest to insulate, but the lowest return on investment is your floor. It will have the lowest temperature differential. May as well do it because it is relatively easy, unless you have an old house with 6 x 6 beams spaced four feet apart …

Replacing your old single pane windows with modern double-glazed ones will cost a fortune and only improve each window from an R-1 rating to about an R-2 to R-4.

You can check to see if your walls have insulation in them by removing a piece of baseboard trim and looking for it by chipping a small hole in the plasterboard. You can have professionals (and I use that word lightly) blow insulation into the walls by cutting six-inch holes along the top of the walls. The insulation will get hung up on wires and fire-blocking, and it will also settle with time leaving the top without insulation and the bottom compressed. There will also be the potential for moisture problems. There are other things you can do short of ripping down the plasterboard, but there is no easy way out with walls. Mine are R-11. I ripped down the lath and plaster to do it many years ago.

The very cheapest thing to do is look for holes and cracks to plug, especially if you don’t have a good fireplace damper. You can stick a piece of foam in the flue with an obvious, impossible-to-miss, handle hanging down into the burner box in place of paying to have a damper installed.

Hopefully, by this time next year I will be able to report that my family has reduced its total energy use by 80 percent without sacrifice or undue expense. By swapping a 24 mpg Outback with a 48 mpg Prius and a 15 mpg Cherokee for a hybrid-electric bike we have already managed to reduce our car footprint roughly 80 percent. We still travel the same number of miles without sacrificing time, comfort, or cash.

I proved (mostly to myself) that a 100-percent, solar-powered home is not just another Internet urban legend, when I designed my Hybrid Solar Home for the Pacific Northwest that would use solar energy for all of its needs, power and heat (at least on paper). Great if you’re in the market for a custom designed home with unobstructed southern exposure, but the big ticket item is going to be retrofit of existing structures.

Next up, reduce the electric bill. The two big-ticket items will be the refrigerator and dryer. This is going to be interesting.