New passive solar home design consulting
The Davis' preliminary sketches were of a simple ranch-style home, with the main axis of the home running east west. The garage and main entry were to be located on the northeast corner of the home. A master bedroom was in the southwest corner, with the closets on the western wall, and a master bath to the east of the closets.
The home will be nicely situated next to a western grove of fir trees, aiding in blocking much of the cold western prevailing winds. There will be about 700’ of gravel driveway from the northern road, 1100’ below the home. A pond will be dug east of the home.
Having a long driveway on a north slope may be difficult due to snow not melting quickly. Also, plowing a long driveway can become a difficult burden.
The couple did explore these issues, and noted that the sun exposure was sufficient to quickly melt the snow
For the pond, assess drainage around the home, as well as the pond becoming a potential water source for gardens
Both ideas will be a priority when the final location will be finalized.
Time-of-use room design
The couple’s lifestyle - their passions and pursuits, and their day-to-day needs were analyzed from a custom questionnaire filled out by the couple. The following key aspects were discussed:
An office for writing fiction was to be located along the middle portion of the northern wall. An entry porch was also to be located on this wall so that the couple could sit and look out at the northern views.
A room located at a home’s northern wall, and with an exterior porch, will be very dark. What little ambient light would enter this room would be almost eliminated from the porch. Also, it was discovered that the husband prefers to sleep in a cool, dark room, yet their master bedroom was located in the warmest corner of the home- the southwest corner. After discussing these issues, it was agreed that it was best to locate the office in the sunny and warm southwest corner and the master bedroom in the middle, northern room.
Day-lighting and natural ventilation techniques
The western wall, north of the relocated office had closets located here. The bathroom was positioned adjacent to the closets.
The western wall receives the warmest, most intense light of the day. By swapping the bathroom and closets, the couple could enjoy a bright bathroom, but could also have good daylighting in the closest from high transom windows, letting in light from the bathroom.
Closets, pantries, and laundry rooms are ideal rooms for locating along a northern wall. All of these rooms could have high transom windows to let in natural light, but also insulate the home from the coldest north side.
The large number of bookshelves needed to be designed into the home
Bookshelves can serve numerous functions, besides the obvious storage of books. It’s a great sound barrier and works great when dividing sleeping areas from public areas. They are also good insulators, and would work great near northern walls. Good air circulation, however, is crucial for avoiding any mildew problems and the resulting “library smell”.
Locations of windows were discussed to aid in good, natural ventilation, particularly for the large number of bookshelves. Aspects such as difference in height of windows, and direct/indirect exchange of air were discussed and are to be incorporated into the design.
Design of solar heat gain and cooling loads
The details of the Trombe wall were analyzed to determine if this wall could work for this particular house
Based on the house’s north latitude, the average temperature, and square footage of living space to be heated by the wall, it was determined that an 11’-3” tall wall with a minimum thickness of 8” of concrete would be required.
The difficulties that would need to be addressed: the vents and ducts could have potential mold problems in this humid climate, the requirement of insulating the wall at night with insulated curtains, the lack of light in the walkout basement, and the larger foundations that would be required.
The glazing to thermal mass ratio was calculated for a good passive solar design
The square footage of floors and walls that would be directly and indirectly in contact with the sun was analyzed, and it was determined that 102 ft2 of southern glazing could be used. This amount could be increased or decreased in proportion to the amount of thermal mass available. By properly proportioning the thermal mass to glazing ratio, the daily fluctuations of temperatures could be kept to a minimum, thus ensuring maximum comfort.
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