Yes, you can install insulation over ductwork, and doing so can save you money. Without insulation, the HVAC unit must work harder to force warm or cool air around the home, and once the air reaches the vent, it may not be the correct temperature. Insulating HVAC ducts makes your system work more efficiently, saving you money on heating and cooling bills.

Insulating windows without plastic is usually the better method. Outside of simply replacing your windows, you could buy cellular shades, which trap air between the window and the home, add a window film that blocks UV rays and traps heat, or cover your windows with a low-emissivity coating called “low-E.”

We do not recommend fiberglass insulation for soundproofing purposes, especially if you are working on a room that’s part of your living space. Fiberglass insulation is dangerous, and the installation process is hazardous. It is also harmful to the environment. When there are so many newer, healthier non-fiberglass alternatives in the market, the lower cost of fiberglass insulation simply doesn’t justify the harm and danger it poses.

Three signs that you need crawl space insulation are drafts, high energy bills, and mold. Drafts can start in crawl spaces and cause hot or cold air to spread to the rest of your home through holes in the floors and walls. And even if your entire home is well-insulated, you can still feel an unchecked draft from your crawl space and in your utility bill. Uninsulated crawl spaces can let in air and moisture, and because they’re built directly on the ground and difficult to dry out, they are hotspots for mold and mildew.