1. The long side of the house should be facing south and should NOT be shaded with high foliage or trees. In the northern hemisphere, the south facing side is referred to as the "sun side" of the house. In the Southern hemisphere, the sun side is the northern side of the house. This should also be the side with most of the windows. Very few contemporary developers know how to or care to correctly orient a house so it takes some looking on your part. This orientation will give you the most advantage for passive solar gain. The roof should have a substantial eave (somewhere between 2 and 3 feet). The correct eave width will allow maximum amount of sun to enter the windows in the winter and will shade the windows in the summer. Here's a link for calculating the correct eave width at your latitude (you'll need to convert from metric with this calculator). Our latitude in the Morongo Basin is 116. Some green builders say the sun side eave width should be no more than 25% of window height and recommend keeping any further coverage flexible by using retractable awnings or a trellis of vines that lose leaves in the winter.
2. Look for shading from either porches or trees on the west and east sides, particularly the west. In the summer, the day will be the hottest in the afternoon as the sun moves to the west.
3. Look for the land to have a slope of no less than 4 % and no more than 25%. This will be very helpful for harvesting water run off and for using gravity for greywater systems. No matter how great the view, look for the house to be sited somewhere down the slope, not at the top. Desert winds can be fierce and you'll want as much protection from them as possible.
4. Look for washes and gullies that show water movement on the land. These are places where water can be captured by slowing it, spreading it and sinking it into the land. In this way you will begin to rehydrate the land.
5. It will be a great perk if all the windows in the house are dual glazed. This will help a great deal to keep the house temperate. Of course, it will also be very helpful if the house is well insulated.
6. Even the desert has micro climates. Some areas get more rain than others. Try to locate in the areas of highest precipitation (usually up against the mountains). Ask people in the immediate area about rainfall.
7. Most desert houses use swamp coolers. These simple and very effective cooling devices use evaporation to cool air that is drawn over wet pads and then blown into the house. They are far more effective and energy efficient than air conditioners. The best place for a swamp cooler is on the north side (shade side) of the house. Although many desert homes have the swamp cooler on the roof, in my opinion this is the worst place for it to be. Not only is the sun constantly beating on it and heating the water inside it but any undetected leak is liable to damage the roof.
8. One of the most destructive practices of new home builders in our area is scraping the land - removing all vegetation in a large swath around the house. This is basically an ecological disaster. This contributes to particulate dust pollution, removes essential animal habitat and food source and destroys the intricate microbial balance of the native soil. Look for land where this kind of destruction is at a minimum and then work to restore the balance by planting food producing and medicinal natives.
For superb information on landscaping with our local native food and medicinal plants go to Robin Kobaly's http://summertree.org/
The beautiful news about permaculture is that it can be done anywhere; on dead flat land, mountainous land, house oriented all the wrong way, in the driest of the dry climates and in the monsoon howling tropics. This list just makes it easier if you've decided that the desert is your choice.
Long side of house faces south. Picture taken in
late May when eaves already block the summer sun.
Large Tamarisk shades west side. House is sited
about half way down a gentle slope. The scraped
land will be planted with food producing and
medicinal natives. Demolition work on interior
has just been completed. Next step is long row of
dual glazed windows on south side.
dual glazed windows on south side.