Friday, March 14, 2014

Making an old house more energy efficient

Why did a couple of sustainable living enthusiasts choose a leaky, drippy old house to call home? Shouldn't we be building a passive solar cob house or something?

Well, we just love old houses, and we want to play a role in helping one stick around for many more years to come. I could go on and on about the virtues of an old house, but that's a different post. The point is, living in an old house doesn't have to mean living in a wasteful house.

We don't have a flow chart like our friends over at D.I. Wine and Dine (and you should really check them out if you want real information about retrofitting a house). But, here's what we've done so far to

1. Conserve, conserve, conserve! We had an energy saving specialist do a "home energy audit" this winter, part of a state-wide program to reduce home energy use. We anxiously handed over our heating and electricity bills, waiting for our reprimand. "Wow," the inspector said. "You guys don't need my help. I can't believe how low your heating costs are considering how old this house is!" So, how did we manage this? We didn't think we were doing anything special. We keep our thermostats set to 65 in the winter (we have gas hot water heat). We use CFLs (and we forget to turn them off when we leave the room quite a bit). We don't flush the toilet every time we use it, and we don't take more/longer showers than we need to. Apparently just these common sense measures are enough to shock a professional home energy inspector. And they're basically free to implement. Go figure.

2. High efficiency gas boiler. The boiler our house came with was oil, and it was shot. We weren't sure it would make it through even one winter, so we replaced it immediately with an ultra high efficiency gas boiler and indirect hot water heater. People with more experience than us will note that we did this out of order--we should have added insulation an air sealing first to avoid purchasing an oversized unit. We didn't know, and we didn't really have time to wait. C'est la vie.

3. Stop the drips. Ok, our upstairs bathroom is a disaster. All of the fixtures are from 1945 or earlier and they all leak/drip. We used the bathroom for awhile, but ultimately decided to shut it down until we can renovate the room. Guess what? Our quarterly water bill dropped by 40%! Holy cow were we wasting a lot of water. So, til we can get it fixed, it's the downstairs bathroom only. This week we also replaced the 2.5 gpm shower head with a 1.5 gpm one. That'll save us 10 gallons per 10 minute shower.

4. And the drafts. That home energy inspector qualified us for some free air sealing. Since it was free, and administered by the state via private contractors, it took dozens of phone calls and about 6 months before someone finally showed up at my door. But hey, you can't argue with free. The contractors did a blower door test, to my geeky delight (I've always wanted to have a blower door test!) and declared our house "pretty leaky, but not as bad as a lot of old houses". With a starting number of 3400 (the units escape me), they set to work. After 5 hours of work, they re-tested the house. 2866, which missed the goal of 2700 they were aiming for. Still, this should result in reduced heating costs for us this winter. And did I mention it was free? Stay tuned. And if you live in Massachusetts, go to right now and sign up for your own energy audit. You can do one each year!


Eric said...

Are you using your existing radiators with the new boiler? Are they baseboard or old steam radiators? (I'm curious because we also have hydronic heat).

The oversizing probably isn't that big of a deal, especially since your high-efficiency boiler probably modulates gas input.

That's awesome you got free air sealing! The units are most likely cubic feet per minute (CFM).

Libby: said...

I wish we had been able to keep the existing radiators, but they weren't the kind that could be easily converted to hot water from steam. We have baseboards, which does take away some of the character of the house.

Thanks for the units help, Eric!