Green Your Crib: Keep Cool Without the AC
As we increasingly experience summer weather during winter months, some Santa Barbarans are deciding to add air conditioning to their homes. The downside is that air conditioning draws significant electrical power that is generated mostly from fossil fuels, thus exacerbating the warming that this equipment is designed to counter, at least indoors. Even when powered by renewable energy, the production of any AC equipment can use a lot of resources. So if not air conditioning, then what other options make sense?
One possibility is adding exterior shading devices over windows that are bathed in the sun’s heat. These devices include fixed eyebrow extensions; trellises (with or without deciduous vines); vertical louvers or fins for east- and west-facing windows; canvas awnings that are fixed, manually adjustable, or even motorized; or mesh solar shades that slide in vertical tracks on either side of the window, which can cut out as much as 80 percent of the heat. These exterior shading strategies are more effective than interior-shading blinds or curtains and can dramatically reduce building peak heat gain while also improving visual comfort by controlling glare and reducing contrast ratios.
Another option is to change the glass in south-facing windows to high-performance glazing, which greatly reduces the need for exterior shading elements. To carry out this change, sometimes just the glass panels in old windows can be swapped out. At other times, the entire window frame and sash need to be replaced to get optimal performance. This latter approach is expensive but does have advantages beyond just keeping unwanted heat out.
Top-performing windows can also attenuate outside noise and keep the place warmer on cold winter days. Putting an operable window in a key location, where perhaps none existed before, can allow residents to open a house to cool early-morning air on hot days, thereby implementing an effective natural cooling strategy.
You might also want to consider adding insulation to your existing walls and attic. In most cases, this is less expensive than installing air conditioning equipment and helps to keep the house not only cool but also quiet (or warm when desired). It definitely saves on heating and cooling bills. There are at least five materials and approaches to insulating existing houses: loose-fill cellulose, dense-packed cellulose, loose-fill fiberglass, dense-packed fiberglass, and injection foam. Application skill is important for achieving a complete, high-performance thermal barrier, so getting the help of a professional is advisable.
A final, low-cost cooling option is to install Casablanca ceiling fans in the main rooms of a house. These don’t lower temperatures, but they do move air, making us feel cooler. If a room has a central ceiling light, a combined fan-light fixture can easily replace it.
Be sure to explore these options before automatically turning to air conditioning.