This is intended to be a ramble on beating solar heat effects, the failure of our air conditioner, air conditioning in general, and how we cope without one.
We are fortunate in our present house when it comes to climate control. We are sandwiched on the East and West by other houses that share a common, insulated, double stud wall with double drywall thickness on the living side of the wall. The adjoining townhouses have occupants who I assume make some effort to keep their own areas comfortable, and anyway with all that shielding from the elements there is little heat gain or loss from those sides.
When I moved in, we installed fiberglass insulation under the roof between the roof rafters, which made a huge difference in the temperature of the attic, and thus reduced reradiation through the ceilings of rooms without vaulted ceilings. All three bedrooms do have vaulted ceilings; however, the bathrooms and laundry rooms do not.
The house is oriented not quite North and South, but off by a bit- I wonder whether it's aligned on magnetic North without correcting 13 degrees counterclockwise as navigators must do in this area to get astronomical North. That would be a good question to look into, except that I probably won't bother now that I'm moving.
The orientation then has to do with whether and when the sun will strike the windows. In general terms, the south side being where the patio is, and with eaves above the second floor overhanging by about three feet the threshold of the sliding glass doors that look out on the patio, the sun's shadow starts out about four feet from the threshold and by the end of this day near the summer solstice it will come with an inch of the glass but not striking it. The sun will heat the brick pavement of course, and we will keep those doors closed and the area curtained off to reduce radiation through that glass. We recently had these doors replaced and the double-paned glass has been treated to enhance its thermal reflectivity, so we're fortunate there as well. Let's just say that the patio is not a place you want to have lunch on the warmest day of this year to date.
The north-facing windows are the original single pane variety- nothing special about these- each about four by six horizontally. At certain times and certain seasons they will get morning sun- logic suggests that would be in this season. I guess I will have to check these at dawn tomorrow.
The cement slab garage under the same roof on the North side is the coolest room in the house on a summer day, cooled by contact with the earth, and if there are no recently-driven cars inside it can be exactly the right place to do woodworking projects in midday. There is a door that connects the garage with the dining room through a short hallway, and sometimes I will crack open the outer door, open the inner door, set up a floor fan in the hall, and circulate cool garage air into the house on a warm day. That seems to increase comfort in the lower areas of the house: the dining room, living room, and kitchen.
The upper floor, especially the master bedroom on the South, is warmer than the lower floors, day and night. On hot days we keep the master bedroom blinds closed, while allowing some air to exhaust on the North side windows.
The townhouse complex being arranged along a 20 foot drive going East and West, about 200 feet long, is a pathway that channels and accelerates the usual ocean effect sea breezes. I have occasionally wondered whether I could make some kind of sail for gathering in some of that air on the North side and directing it into the bedroom windows and from there through the top floor, but that idea will go unexplored now as well. Generally speaking, the upper floor is about 5 degrees warmer than the lower one of all the windows are open. We tend to spend most of our waking hours downstairs.
Getting back to the dining area, in addition to ventilation via the cool garage, comfort is also enhanced by a ceiling fan with LED bubs, which when set to updraft causes a breeze on the backs of all those seated at the table, especially those near one of the two walls. This is probably the best "civilized" space to be to get through the heat of the day, sans air conditioning.
Of course central air conditioning changes all this. We have not had enough recent experience to fine-tune the distribution of cool air but here's the basics:
The air to be heated or cooled is taken up through a vent inside that aforementioned hallway between the garage and the dining room, runs through the plant which heats or cools it as required, and redistributes the air through equal sized vents throughout the house- two downstairs quite close to the intake, in the living room and dining room, and upstairs, one each in the three bedrooms and one in the master bathroom. The master bedroom has twice the volume as the bedrooms, and the duct to the master bathroom is currently mashed up a bit in the attic and so is throttled down a bit. The air returns downstairs through the open stairwell, unless a bedroom door is closed, which will trap the air or exhaust it through an open window or into the attic.
Some of the airflow can be redirected by use of the downstairs hallway doors at each end. If the garage door is closed and the dining room door is opened, the air will circulate as described above. But if the garage door is opened, and the outer garage is open a crack too small for stray cats (20 feet wide but 3 inches high), and the dining room is closed, then air return will be blocked and fresh air will be drawn in from the garage. Presumably with the house under pressure the air will find places to leak out- through bathroom fan vents, fireplace flues (master bedroom and living room) vents in the bedrooms and the atrium, to the attic, and out under the eaves, or through open windows and doors.
So far, as I've said, the forced air system operation is mostly theoretical. The darn air conditioning quit the first day we wanted to use it, after checking out fine a few months ago So the guy is coming out in a few days to troubleshoot the thing- I expect the coolant has leaked out or the compressor is blown. Of the two a leak might be harder to locate and fix permanently, but cheaper; a compressor replacement would probably cost $500 or more. But it's something we need to sell the house.
This is what I've learned from this house:
Earth-insulated floors do work.
The thermal mass which is the fireplace brick has held its cool temperature.
There are more resources I could make use of in another situation, like prevailing winds.
Other ideas I hope to use include berms, pergolas, water features, thermal masses, and plantings to capture, deflect, and shield living areas and create human-centered Zone 0 and 1 habitat without having to waste energy pumping heat out of and into an inefficient system.
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