Locating Air Leaks
There are various reasons for locating air leaks in your home: to decrease energy consumption because of air leakage; to prevent moisture condensation problems; to avoid uncomfortable draughts caused through cold air leaking in from the outdoors; and to make sure in which the home's air quality is not contaminated through air pollution. The potential energy savings from reduction of air leaks might range from 5% to 30% per year, and the home is commonly much more comfortable afterwards. Make a list of obvious air leaks in your home, e.g., from doors and windows. See if you could rattle windows and doors, because movement means possible air leaks. If you can see daylight around door and window frames, then the door or window leaks. You can commonly seal these leaks through caulking or weather stripping them.
Caulking and sealants are used to seal gaps in exterior walls, floors, and ceilings. They are also used to seal the seam where various building materials meet, such as among the window jamb and siding. These are required where walls meet the foundation indoors and outdoors, at the joints where wall and floor meet, electrical wiring entrances and exits, plumbing entrances and exits, telephone entrances, around exhaust fans, joints among exterior window frame and siding, where chimney meets exterior siding, any air leaks in basement, furnace vent stacks, where door frames meet walls.
Check the storm windows to see if they fit and are not broken. You might also wish to consider replacing your old windows and doors along with newer, high-performance ones. If new factory-made doors or windows are too costly, you could install low-cost plastic sheets over the windows. Check for indoor air leaks such as gaps along the edge of the flooring, and at junctures of the walls and ceiling. Check to see if air can flow by electrical outlets, switch plates, window frames and wall- or window- mounted air conditioners. Look for gaps around pipes and wires, foundation seals, electrical outlets, and mail slots. Check to see if the caulking and weather-stripping are applied properly (with no gaps or cracks), and are in good condition.
If you are having hard locating leaks, you might want to conduct a basic building pressurisation test. First, close all exterior doors, windows, and exhaust pipes. Turn off all combustion appliances such as gas burning stoves, and water heaters. (Remember to turn them back on when you are done with the test!) Then turn on all exhaust fans (commonly located in the kitchen and bathrooms) or use a huge window fan to suck the air out of the rooms. This increases infiltration by cracks and leaks, making them easier to detect. You could use incense sticks or your damp hand to locate these leaks. Moving air that causes the smoke to waver and you will feel a draught while it cools your hand.
On the outside of your house, inspect all areas where two different building materials meet. For instance: inspect all exterior corners whereas siding and chimneys meet; and areas where the foundation and the bottom of exterior brick or siding meet. You should caulk and plug holes or penetrations for faucets, electric outlets, pipes and wiring. Such as for cracks and holes within the mortar, foundation, and siding, and seal them along with suitable material. Check the exterior caulking around doors and windows, and see whether doors seal tightly.