Monthly Archives: January 2016

Efficient House Design and Construction, Part 2

The Bruhl-house living room. Note the "clothes dryer"--- the rail around the woodstove. An energy-efficient method, but also a source of indoor humidity.

The Bruhl-house living room. The very-tall interior flue (barely visible on left of photo) drafts exceptionally well, and we’re very happy with the overall performance of the woodstove. Note the “clothes dryer”— the rail around the woodstove. An energy-efficient method, but also a source of indoor humidity.

(Note— This is a continuation of a post from last year, “Another Tough Cookie: Efficient House Design and Construction“.)

Ok, a longish and slightly technical post here. But, it might pertain to, say, all those people out there who live in houses. To wit—the “topic-of-the-week” between me and Mr. X seems to have revolved around indoor air quality, and the problems that arise as buildings are made more efficient and air-tight. Particularly, the air-related problems the Bruhl house is having, and what exactly the best design going forward might be to remedy those problems. And all of this was triggered last week when I picked up the latest “Energy-Smart Homes” edition of Fine Homebuilding. It contains quite a few articles about air leaks and building durability, one which includes a photograph of a house in Minnesota with the siding off and the house wrap pulled back, which reveals enormous areas of rot and mold caused by air leaks.

energy smart magazin cover

The Winter 2016 edition of “Energy-Smart Homes”; well-worth the cover price.

To catch you up if you haven’t read the post from last April, our house is fairly tight, but has no dedicated ventilation system. Adding one has been on my “to-do” list for years, but it has become more of a priority as I have come to better understand this topic. We currently have fascia and trim boards in at least three places that are rotting from the back side due to air leaks, and the photo in the magazine really made me wonder how much damage is being done that isn’t visible.

So off I went on a reading-binge. And guess what? No real surprise; it’s complicated. In some cases, really complicated. But for the sake of clarity, let me skip rather quickly to some of my preliminary conclusions, and mention the complications briefly as I go.

Ok, the short version—our house is built with stress-skin panels around a post-and-beam frame, Continue reading

Cause for Optimism

Just one of many recent changes---practical electric vehicles for ordinary people.

Practical electric vehicles for ordinary people—just one of many changes in recent years.

If you haven’t noticed, things are changing out there.

I titled the letter to the editor that I wrote last month “A Call for Perspective“, and in it I argued that we all need to take a wider view on issues such as renewable energy, so that as we go forward we can head in directions that make long-term sense for the planet.  Well, the other week I was working with a student on renewable energy topics, and it occurred to me that we also need to keep things in perspective as we look backwards. When we do, we notice that there has been a tremendous amount of change in the last four or five years, and much of it is positive.

So, without turning this into a huge long post, let me just point out some changes, in no particular order. In the last few years, solar and wind generation have each more than doubled, both in the U.S. and worldwide. Solar prices have dropped by half, (and will likely continue to drop), PV cell efficiencies have gone up, and wind power is now one of the cheapest ways for utilities in many parts of the country to add capacity. Continue reading