The Lake Saint Louis Green Advisory Committee (GEAC) reminds residents that you can always reduce your energy consumption at your home. There are several no or low costs ways you can reduce your utility costs, while reducing your carbon footprint which collectively has a positive impact on our planet. Cost and energy savings can be attained during all times of the year, with summer and winter savings being more noticeable in our region.
Make sure all your doors, windows, and wall penetrations are properly sealed. Because colder air moves towards warmer air, gaps in walls or around windows and doors allow for cold air to escape into the heated interior in the winter and for air-conditioned cooler air to escape to the exterior in summer months.
There are several places where it is important to insulate your home’s building envelope from the heat of summer and cold of winter. In our region of the country, it is recommended residential attics are insulated to an R-value of 38 to 60. As an example, if your attic has 6” thick batt insulation installed between the joists of your attic floor, you can add 5“ to 11” of blown in insulation to bring your attic R-value to the recommended levels. Depending on the size of your attic, these improvements can cost as little as $100 to $200. Floors, especially those over the outdoors or indoor unconditioned spaces, should be insulated to an R-value of 35 to 30. For exterior walls, many homes are only built with 2×4 wood studs, with 3 ½” of batt insulation, which only provides an R-value of 11, when 16 is recommended. When replacing exterior siding, you can lower your utility bills by adding R-5 insulative wall sheathing before installing your new siding. If you find that exterior walls are not filled with insulation, there are many options to insulate these cavities. Another area is between floor joists that attach to top of concrete crawl space or basement walls. Batt insulation should be solidly installed on top of the concrete walls between the joists.
With sealing and insulation improvements, it is important to have your mechanical contractor verify that your ventilation system is working properly, especially in winter. With less heated air escaping to the exterior it is best to make sure your home is ventilated properly to eliminate the buildup of carbon dioxide and stale air inside your home.
https://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table, “Recommended Home Insulation R-Values”