Small house up North
I’m currently planning a home for when I retire. It’s in a maritime region, 57 degrees N with 3200 HDD. I’m considering a small house (~1000sf) on a single story. The selected site has clear view to the south and the long axis of the house can be aligned E-W so solar is an obvious consideration. The house will be heavily insulated and built tightly. I would like to know whether or not a combination of direct solar, thermal mass and solar P-V would be a good starting point for the design. I have access to my own wood for winter warmth.
thanks
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Peter,
Q. "The house will be heavily insulated and built tightly. I would like to know whether or not a combination of direct solar, thermal mass and solar P-V would be a good starting point for the design."
A. The starting point for your design are the two first points you mentioned: your house should be heavily insulated and built tightly.
The next principle I recommend is to buy high-performance windows. In your climate, that probably means triple-glazed windows.
So what comes next? "Direct solar"? I guess you mean designing your house according to passive solar principles. It sounds like you plan to do that: orient the long axis east-west, and put most of your windows on the south side. Design your overhangs to provide summer shading on the south side.
"Thermal mass"? Maybe. I would put that fairly low down on my list. For more information, see All About Thermal Mass.
"PV"? Well, you don't have to install it yet, but you can if you want. As long as you plan to include an unshaded south-facing roof that has no dormers, plumbing vents, or chimneys, you are all set. You can install the system at any point in the next few decades.
For more information on this topic, see Green Building for Beginners.
Martin - Thanks for a prompt and helpful answer. I don't know if it makes a difference to the advice on vapor barriers in 'Green Building for Beginners' but I am more than 200 miles from the Canadian border - east rather than south. The roof for the house is completely uncluttered on the south side - the chimney for the wood burner is on the western gable end. The current thread on Net-Zero has certainly caught my attention.
Putting a masonry chimney on the exterior wall of a house is pretty lossy. It would be better to put it somewhere such that it's thermal mass is fully inside the insulation envelope, and penetrating the north facing pitch of the roof, so that it never shades your PV.
What do you estimate your 99% outside design temperature to be? In Newfoundland & Labrador it ranges anywhere from -18C to -34C, depending on location, but if you're off on a smaller island surrounded by water and closer to the Gulf Stream it might be only -15C or so.
Dana,
The chimney (probably more of a stove pipe than a chimney) will run internally up nearly to the ridge and then out through the wall. The weather statistics are pretty benign - monthly averages run from 36F up to a whopping 64F. I don't know how that would translate to 99% values but I would be surprised by a long period lower than 10F. Water management will be an issue with monthly figures of 11 to 20 days per month with precipitation. Overhangs, rainscreen siding, ground drainage...