House Design and Energy

The most critical factor to take into consideration in house design is to have a very well-insulated house to start with. Upgrading insulation, in an existing house, to improve conservation of energy, is normally the most cost-effective way of reducing the overall cost of heating and cooling.

Maximizing the area of glass on the south side of a house will enhance solar gain. Since the sun is about 64 degrees above the horizon in the middle of the summer (at noon) and only 17 degrees above the horizon in the middle of the winter, it is best to have a four-foot roof overhang above the windows. This allows the windows to admit sunlight during the colder parts of the year, but cuts off the summer sun.

Reducing, or better still, totally eliminating north-facing windows, is a good idea since they gain no direct sunlight and lose heat during the winter. Excessive areas of windows on anything but the south side of a house generally result in unwanted heat gains/losses throughout the year.

High-efficiency windows are useful in keeping heat in a home during the winter and reducing glare and solar gain during the summer. Thermal shutters and heavy drapes also help to insulate windows.

Planting deciduous trees on the east and west sides of a house reduces overheating during the summer. Then when they lose their leaves in the winter they allow winter sunlight to enter the windows.

A solar water heating system can provide all hot water during the summer months and about 70% on an annual basis. Commercial systems are expensive but homemade systems can be quite inexpensive. A low-cost barrel-based heater has already been described in an earlier article.

Attached greenhouses on the south side of a house not only provide food, but can also act as supplementary heaters. On sunny winter days excess hot air can be directed into the home.

Unless you live in a remote location without access to BC Hydro, it is debatable whether it is worth installing photovoltaic cells (PV solar cells) to generate electricity. The Canadian government needs to offer significant incentives to get the photovoltaic industry off the ground; many other countries are offering such incentives.