GeekPi

The Cold Hard Truth

Very chilly winter nights are now grasping the Seattle area, with the low temperatures now dipping into the single digits. Some months ago, I pledged to keep my maximum, monthly energy bill to below $100 but seeing as November was at $98.28, and the temperatures have plummeted since then, I highly doubt December is going to stay below my goal.

So far I’ve seen a 30% drop in my energy consumption over last year, which is noteworthy, but the cold weather heat loss throughout my house has been running the heat pump to its limits. I knew this when I put it in, as I sized the unit (the smallest LG makes) for a home that was well insulated. I’m waiting until after the New Year to put up any form of insulation in my crawlspace, and had to resort to firing up a key baseboard heaters to keep the house comfortable. This, combined with the heat pump de-thawing cycling has raised my daily energy consumption to as high as 60 kWh.

The Trouble Areas

To get an idea of where I need to focus on beefing up insulation around the house, I employed my work’s Fluke Ti25 IR imager. The results were very educational. After doing blower door tests this summer, I know the house is sufficiently airtight, but I wasn’t quite sure where it is the leakiest in terms of thermal loss. This is what I discovered and what I need to work on improving.

1. My front door sucks!

   To the right is an image (clickable to enlarge by the way), I took of the inside of the door. Even without an in depth explanation, you can see that sucker is cold, cold, cold. While trying to maintain a comfy interior temperature of 70 degrees, the aluminum threshold of the door is a very chilly 44 degrees, and the majority of the hollow core door is in the 50 degree range. An easy way to think of an IR imager in the use of energy auditing, the colder the area, the faster the heat is escaping outside, and the more money you’re spending to try to keep the place warm in the winter. The view from the outside is not much prettier, as you can see a very warm door. In comparison to the siding, it is much warmer. You’ll notice however that the LED Christmas lights give off almost zero heat! Moving down to the bottom of the image, you can also see a pretty warm foundation; which brings me to my second point.

2. No insulation in the floor/crawlspace sucks!

   When I started in this energy efficiency endeavor, I knew that I had an insulation problem. More specifically, a lack of insulation problem. Up in the attic, I have a fairly well settled 4 inches of loose fiberglass. Below the floor, I have a vented crawlspace, lacking any form of insulation. I was going to tackle those problems first, however PSE was offering a raging rebate of $2,000 off of a ductless heat pump. I jumped on that bandwagon and incidentally, maxed out my 30%/$1,500 federal energy tax credit for the year, which is why I’m holding off until the New Year to beef up the insulation. A little backwards, I know, but sometimes incentives push you in unforeseen directions.

   So back to that drafty, cold crawlspace. Knowing I had to do what I could to keep that heat in, I bought some Styrofoam inserts to pop into the crawlspace vents. I also cut some extra rigid insulation to fill the void in the access hatch. This did seem to help somewhat with our cold floors, but doesn’t go near far enough, as much of that heat is being absorbed by the ground and radiated out through the concrete foundation. I have a feeling that once this is buttoned up with insulation, it’ll start being much more comfortable around the house. The only question, do I go the cheap route and have fiberglass batt, or go high zoot and put in a soy based spay foam insulation that’ll also air seal the floor. Seeing as the quote I got for fiberglass was about $1,300 for the job (I hate crawlspaces, so I’ll hire someone), I expect the spray foam to be at least double that.

3. My attic insulation sucks!

Yep, upon further investigation with the IR imager, I see many splotchy areas in my insulation, and a couple areas where there’s zero insulation between the rafters (my fault when installing 6 inch can lights). After a little time back in the itchy, cramped attic, I fixed the majority of the  no-insulation areas. While I was up there, I even put a little extra foam sealant around the canlight enclosures. Since they’re insulation contact rated, and being converted to Cree’s LR6 LED lights, I wasn’t too worried about expanding spray foam. One note however, there is no worse of two substances to be working close together as loose fiberglass insulation and super sticky spray foam. A drop will stick to everything and create a heinous ball of sticky, itchy mess. Wear proper safety equipment, like goggles and a respirator when working with either substance.

Poking around the rest of the house, I could see where the thinnest areas were. The problem is that I didn’t have any extra insulation to put in place. The current 4 inches of loose fiberglass only works out to be about R-12 of insulation. The recommendation for a tight house in the Northwest is more than triple that, at R-49. That is definitely an area to work on after the New Year.

4. My Attic Hatch Leaks!

I thought I did a good job at modifying my formerly non-insulated attic hatch, by adding about 6 inches of ridged insulation on the back and sealing it off with weatherstripping, but as you can see, air is still leaking in from one edge. I’ll have to rig up a way to ‘baton down the hatch’ tightly to the weatherstripping. I’ve seen a few ideas for this, but have yet to find an elegant solution for my in place door.

One area I haven’t mentioned, windows. This is an area that always irks me. Unless you have ancient, leaky single paned windows, you likely don’t need to replace them, and will save much more money focusing on air leakage and under insulation spots. If you go back towards the images in the beginning of this post, you’ll notice the shot of the front of the house. For the most part, the windows weren’t that bad. They’re older double paned, cheap fiberglass, that don’t work very well (condensation and double hung windows that won’t stay open), yet they are vastly better at keeping the heat in than either the door or the foundation. Don’t fall for the window company advertising. When looking to improve your home’s energy performance, leave windows on the very last of your list. You’ll make your money (and energy) go much further focusing on other areas.

How well has all of this worked? We’ll just have to see when the December utility bill shows up. Worst case, I’m hoping for no more than $140 for this uber cold December. I believe with proper insulation in place, my under $100 goal can be within reach.

Share on Facebook