11.3 Sustainable energy practices: climate action planning  (Page 5/17)

Tighten up the building envelope

The building envelope (e.g. walls, windows, foundations, doors, and roofs) greatly affects how efficient a building will be in maintaining comfortable interior temperatures. Insulation in walls and seals around windows and doors are prime factors. Low-emittance coatings (microscopically thin, virtually invisible, metal or metallic oxide layers deposited on a window or skylight glazing surface primarily to reduce the U-factor    by suppressing radioactive heat flow), gas-fills, and insulating spacers and frames can significantly reduce winter heat loss and summer heat gain through windows.

Double-pane, insulated glass windows significantly reduce the load on the heating and cooling systems and drafts, which in turn, reduces energy demand. These projects are most financially beneficial when leveraged as part of other renovation projects. Existing windows can also be "fixed" with weather-stripping and caulking to seal them from air leakages. Good storm windows over single-pane glass windows can also provide similar insulation to double-pane without the need for the larger financial investment and the creation of waste that replacement entails.

Insulation in the attic or roof of a building and at the "seam" of the building between the basement and first floor, as well as the walls can be installed or increased to retain the heated or cooled air for building or home. Related to insulation is sealing of opening to prevent air from leaking out (see Figure Diagram of a Leaky Home ).

Maintain or upgrade heating, ventilation and air-conditioning systems

Heating, ventilation, and air-conditioning systems in commercial and industrial buildings need to be properly monitored and maintained for the most efficient function. This is often not done well after a system is installed because not enough resources are dedicated to maintenance of systems. Processes related to building commissioning make sure that buildings are ready for service after equipment installation and testing, problems are identified and corrected, and the maintenance staff is extensively trained. If this was not done or the effect has worn out, buildings may undergo recommissioning , or if it was never commissioned, retrocommissioning can be performed.

If equipment such as motors, fans, boilers, and chillers are too old to fix or inefficient, they can be replaced or retrofitted with more energy efficient equipment. Building automation systems (BAS) use electronic technology to control and monitor building systems. They can schedule temperature settings and ventilation needs based on actual or scheduled occupancy so energy can be saved when space is unoccupied. In homes, this is typically done with a programmable thermostat that can set the temperature points to conserve energy during the day when a home is unoccupied and then go back to occupancy settings when the family returns.