In cold, mild and mixed climates, homes should be primarily designed to respond to their heating requirements. Cooling requirements come second.
Homes - in these climates - should have high levels of insulation and high performance windows, to reduce heat loss during the heating season. Their main living areas should be oriented to the winter sun, and protected from cold winds, as much as possible. That's critical for energy savings.
The six pillars of the cooling strategies in cold climates
1) High levels of insulation, 2) Shading, 3) Cool roofs, 4) Ventilation and Breezes 5) Window films (or energy efficient windows) 6) Control of internal sources of heat.
Fortunately, these features do not collide with strategies for the cooling season. High levels of attic and wall insulation are also critical to protect the house from unwanted heat gains.
You just have to add the features that are crucial in cooling strategies:
»» summer shading;
»» roof reflectivity;
»» a proper landscape;
»» low-energy windows (or window films);
»» natural ventilation features.
Cooling Methods for Cold and Mild Climates
- Window films (in outdated windows);
- High levels of attic insulation;
- Awnings, drapes, shades, shutters and similar devices;
- Natural ventilation;
- Use of circulation and ventilation fans;
- Control of internal sources of heat (appliances, ovens, light bulbs...);
- Use of roof reflective coatings;
- Use of light colors in walls and roofs.
- Use of trees, shrubs and lawns;
- Caulking and sealing air leakage paths.
Homes with these features rarely need air conditioners.
Shading & Landscaping
Use shades, blinds, shutters, awnings and other shading devices in your cooling strategies.
Also consider the use of deciduous trees and shrubs to shade your windows, roofs and walls. Landscaping is critical for energy savings.
Windows & Skylights & Window Films
Windows are often the main source of unwanted heat gains, and window films a cheap and very effective way of blocking them, in low-energy windows.
If you are building a new home, consider carefully the placement and the size of its windows, as well as their type and glazing coefficients. When choosing their type, prefer casement windows. They are great to minimize air leakage and to provide natural ventilation and deflect breezes. See: Breezes and Natural Ventilation.
Be very cautious with traditional skylights: though useful for ventilation strategies, they can be a huge source of unwanted heat gains during the summer and a major cause of heat loss during the heating season.
Shingles, tiles and metal roofing can now benefit from reflective coatings, able to reduce unwanted solar heat gains without any significant negative impact during the winter season. Roofing membranes and roof coatings can also be applied to existing roofs to reduce cooling bills. They too are critical for energy savings.
See: Roof Cooling Guide
Properly sized and located overhangs will block solar heat gains during the summer months, when the sun is higher in the sky, without reducing them in the winter.
Breezes & Natural Ventilation & Fans
Whatever your exact climate, consider breezes and natural ventilation. They are a key element in any cooling strategy.