Proper weatherization happens in two phases—insulating and air sealing. It’s the same as getting dressed for a winter day, Wittmann said. “You wear a sweater for ‘insulating’ but you wear an outer layer for ‘air sealing.’”
Insulation & Roof Ventilation
Inadequate attic insulation can contribute to as much as a 20 percent loss in heat in the cold months, you can read more about the exact science, it’s actually pretty fascinating. Paired with poor roof ventilation, it’s also a leading factor in ice damming.
Homeowners should inspect the attic space for properly installed insulation. “The recommended amount based on today’s standards is 16 inches to 20 inches total—R-49 to R-60,” Wittmann said. Although this can be achieved with rolled insulation, he prefers professionally installed blown-in fiberglass insulation, which can also prevent the growth of mold when moisture is present in the attic space.
Using baffles in the rafter spaces will help promote the draw of outside air from the eaves or soffits and can help ensure that insulation is pulled back away from intake ventilation so that it covers the warm inside wall space.
“Inspect bathroom or kitchen exhaust fan pipes and damper vents to be sure they’re in proper working order,” he said. “Insulated exhaust fan pipes can help reduce the heat-cold transfer of energies.”
Roof ventilation is a key factor to ensure that the attic space keeps a cold temperature in the winter. Although a properly balanced intake and exhaust system can be achieved with additional vents, Wittmann recommends working with a skilled professional due to the formulas used to determine the balance and the materials that can be installed.
It’s tough to predict when open-window weather is done in Wisconsin, but at that time, homeowners are advised to walk through the inside of the house to ensure that every window and storm window is shut and locked. “This is a good time to address any issues or deficiencies with the windows such as leaks, deteriorated or missing weather stripping, or window seals that are compromised,” Wittmann said. A hazing or cloudy appearance between the panes shows a window seal problem. “If seals are broken, it will usually means that the window itself is compromised and will require replacement.”
If the windows are wood, homeowners should check that the interior and exterior wood is in good shape and not deteriorated or rotting. “Also be sure that the interior of the wood window is clean of dust and debris, since condensation on the glass in the wintertime can react with the dust and wood and cause the growth of mildew and mold,” he said.
If the windows are old, drafty, or deteriorated, new windows made of fiberglass, like Marvin’s Infinity fiberglass replacement windows, can help improve the functionality, energy savings, strength, and appearance.
Check entry doors for any deficiencies such as opening and closing issues, deteriorated or missing weather stripping on the bottom threshold and sides, loose hinges, or cracks in the panels (if the doors are wood). Newer doors tend to have replaceable weather stripping, but older units may require aftermarket or universal kits. “Most new entry doors come equipped with better weather stripping—some even magnetic-based, just like a refrigerator door—and insulated cores,” Wittmann said.
Next, homeowners should take a look in the lower level (basement) of the house. “Air sealing and insulating the area where the top of the basement wall and house foundation meet will reduce the ‘stack effect’ where air from a lower section of the house is pulled from openings located from the upper sections of the house, causing a loss in heat”, he said. “It will also help to reduce and eliminate gaps or holes that small rodents can get in through.”
Finally, homeowners are advised to ensure that fireplace dampers are closed until the fireplace is used. “If the fireplace isn’t used on a regular basis, there are devices that can be purchased to temporarily seal the chimney flue to retain the warm air inside the house.”
A professional home energy audit would provide homeowners with detailed knowledge about the house’s deficiencies and areas that could be improved. “These tests can result in a rather long list of areas for improvement,” Wittmann said, “so it’s best to consider which projects will make the most sense and provide the best return on investment.”