After much waffling, Ted and I decided to bite the bullet and go for Passivhaus certification. More on this soon, but in the meantime we're busily weighing envelope upgrades in search of the best (read: cheapest) path to 4.75 kBTU/(f2year).
I am superstitious and have no immediate plans to change the website name. The web address, of course, will not change. I am now grateful that I was unable to get http://www.almostpassive.com, which is boldly carrying out its mission to tell visitors "All You Need To Earn Almost Passive Income Online! "
In other news I made a new house rendering, but don't get too attached because I'm likely to change it again in a few days. The new rendering places the solar panels on the top awning, which will be almost entirely unshaded and can fit 4.76 kW of DC goodness.
Things that will change in the next rendering are:
- The colors, which are currently quite ugly. We may also change the ratio of cedar shingle and reverse board and batten siding.
- The terrain and foundation, since our building site is a wooded rocky hillside and not an eerie CAD plain.
- Awnings will appear over the lower windows, though they might be removable in some way to allow full winter heat gains.
- A solar collector for hot water might appear in the gap between the two groups of windows, assuming we can afford it.
More to come!
I'm confused. I thought the Passivhaus rating was 10kWh per square metre per year, i.e. 3.6e7 joules per square metre per year (about 1 watt per square metre), 3.3e6 joules per square foot per year, which is about 3000 BTU per square foot per year.
Ah, 15kWh/m^2/year, which is 4.75 *k*BTU/sf/year.
So there's a factor of a thousand in there somewhere. :-)
Have you guys considered going with exterior shades instead of the awnings.... They'd be far more effective in blocking the sun when you don't need it, while not blocking any sun when you need it.
Yes, that's exactly what I've been thinking of late. We need to connect with Camilo, our consulting architect and overall aesthetic guru, but I'm currently envisioning removable exterior louvers.