If your home needs more insulation, you may want to consider doing it yourself. Depending on where you want to add insulation and your comfort level with completing the project, installation could be a weekend do-it-yourself project.
Determine where you need insulation and how much.
Before you start or make any decisions, you should determine where you need insulation and how much of it you need to install. To determine how much insulation you already have, check to see if your batt insulation is labeled with an R-value or calculate your R-value with a simple formula.
Should you do the job yourself?
It depends. Consider the following:
- If the space you want to insulate is open and accessible—This would include unfinished attics and basements, not walls or ceilings unless a renovation is ongoing that allows access
- The type of material you want to use—Batts or rolls are typically installed by homeowners while other types of insulation generally require professional installers (though blown insulation equipment can be available for rental)
- Your level of comfort and skills to take on the job
- Any safety issues that may be present which might make the job more suitable for a professional
The easiest and most common places to do a DIY insulation project are in unfinished attics and basements. However, before you make the final decision and start installing insulation yourself, you should inspect these areas. A professional should be called in to correct problems and complete the insulation job if you find any of these conditions or issues:
- Wet or damp insulation indicating leaks
- Moldy or rotted attic rafters or floor joists indicating moisture problems
- Kitchen, bathroom, and clothes dryer vents that exhaust moist air directly into the attic space instead of outdoors
- A history of ice dams in the winter (an indication of serious air leaks and insulation problems)
- Little or no attic ventilation
- Knob and tube wiring (pre-1930), which can be a fire hazard when in contact with insulation
- If you have many unsealed and uninsulated recessed “can” lights, special care must be taken when insulating around these fixtures1
- Possible presence of Asbestos
Asbestos was once common in insulation products, but is no longer today. If your home was built before 1975, it is possible that the insulation is vermiculite, which can contain asbestos. Vermiculite is a lightweight, pea-size, flaky gray mineral. If you have reason to believe existing insulation may be vermiculite, do not disturb it and have it tested by a professional for asbestos. Your local health department, or possibly an insulation contractor, can help you identify means of getting this testing done.2 If it is determined that asbestos is present, a professional needs to remove the insulation.3
Investing your time in the job
With enough time and attention to detail, adding insulation in an attic is something most anyone can do. However, taking the time to inspect and possibly remove old insulation, find and seal all air leaks and then properly install new insulation can be tedious.
Actual job times depend on the project, but generally installation is a full weekend project entailing: Inspection, identifying needs for materials, purchase of supplies, and completing the labor. While the whole process may take time, the installation step may only take a few hours, depending on the size of the job. Plus, saving money on professional installation can make your time worth it.
There is obviously a significant cost difference between hiring a professional vs. doing it yourself. Costs vary significantly by size of the home, location and accessibility of added insulation, etc., but you can expect the cost of a professional job to be two or three times more than just the cost of the materials you’d need to do it yourself if you purchase fiberglass or mineral wool insulation. For other product types, professional installation can run even higher. There is no DIY spray foam insulation option for re-insulating an attic, and professional installation can require you to vacate your home for up to 24 hours due to dangerous compounds released during both the installation and curing process.