How Much Does Basem*nt Insulation Cost? (2024)

Insulating any part of your home is typically one of the best investments that you can make as a homeowner. The basem*nt is an area where plenty of cold air resides, but adding basem*nt insulation can stop any cold leaks, increase energy efficiency and reduce energy bills. Plus, sealing a basem*nt can prevent moisture issues like mold and keep pests out of the home. Insulating a basem*nt is one of the first steps toward finishing a basem*nt, which adds living space to your home and increases its value.

Is It Worth Insulating a Basem*nt?

Determining whether it’s worth insulating a basem*nt depends upon your needs and your climate. Energy Star provides a climate zone map that homeowners can use to determine the appropriate insulation they need based on R-value. Building Science Corporation has a good guide for basem*nt insulation for climate zones four through eight. Homes in climate zones one to three typically don’t have basem*nts.

The Environmental Protection Agency estimates that homeowners can save up to 20% on utilities by insulating parts of the home. By insulating a basem*nt, a homeowner can expect to recoup the installation costs in less than two years through energy savings.

Types of Basem*nt Insulation

Rigid Foam

Rigid foam insulation is long sheets of insulation, often pink in color. Rigid foam typically runs more expensive than fiberglass insulation. Rigid foam insulation is also known as XPS and extruded polystyrene insulation. Rigid foam insulation boards vary in thickness up to two inches. Each inch of thickness represents an R-value of R5.

Rigid foam insulation kits are available, but individual boards vary in cost from about $15 to $35 per sheet, which can add up quickly if you have a large basem*nt.

Spray Foam

Spray foam will come in open cell and closed cell variety. Contractors often suggest using open cell spray foam for areas above ground level and closed cell in below ground spaces. Closed cell spray foam is an absolute vapor barrier, which prevents moisture from moving through it, but it can also hide leaks that can lead to mold. Open cell spray foam won’t retain water and leaks will be visible.

Closed cell spray foam is denser than open cell spray foam and has an R-value of 7 per inch. In order for closed cell spray foam to perform as intended, there will need to be a complete vapor barrier between the concrete and interior building material. Some contractors will suggest installing exterior wall studs at least an inch away from the wall.

Spray foam insulation should be done by a professional because of the hazards of working with spray foam and the precision needed. Once applied, it typically takes a day for spray foam to cure.

Fiberglass Batt

Fiberglass batt insulation is also known as blanket insulation because of its pillowy appearance. Fiberglass batt does come in flat pieces of either fiberglass or mineral wool. Some fiberglass batt insulation will come with foil or paper facing, while other types won’t. The need for facing depends on the climate zone of the home. Fiberglass batt is one of the more inexpensive insulation materials available.

Anyone who works with fiberglass batt will need to protect themselves with a mask and protective clothing because fiberglass is a skin and lung irritant. Fiberglass batt is more DIY-friendly than other insulation materials.

Blown-in

Blown-in insulation, or loose-fill insulation, is sprayed into place with special insulation tools and is typically used in attics. Blown-in insulation is often made of fiberglass, cellulose or mineral wool. Cellulose has a tendency to hold water more than other insulation materials. Blown-in insulation typically gets used in finished areas of a home and can fill spaces between existing wall studs.

Homeowners must address any moisture issues prior to applying blown-in insulation and note the location of electrical boxes. To fill existing walls, homeowners have to find a place to drill in order to fit a hose in to blow in the insulation. Homeowners will often need a vapor barrier in place if they choose blown-in insulation that touches concrete.

Radiant Wall Barrier

For homeowners who don’t want to finish a basem*nt, but still want to insulate it better, a radiant wall barrier is an option. Radiant wall barriers use a reflective material, like aluminum foil. Some companies tout that a radiant wall barrier will help retain heat in the home and protect a basem*nt from moisture by creating a vapor barrier and a path for water.

Basem*nt Insulation Cost Per Square Foot

Foam Insulation Cost Per Square Foot

Basem*nt Insulation Pros

• Lowers heating costs by around 20%
• Serves a first step to finishing a basem*nt, which will increase useable living space
• Incredible return on investment at nearly 100%
• Reduces potential water issues

Basem*nt Insulation Cons

• Initial costs: Insulating a basem*nt can cost thousands of dollars depending upon the size of the basem*nt and the type of insulation used.
• Uncover issues: Once you start looking at your basem*nt, you might find some surprises. Perhaps the home was previously insulated poorly or you find significant air leaks that require more repair than imagined.
• Reduced space: Albeit minor, but depending upon the level of insulation, homeowners might see a reduction in basem*nt space.

Basem*nt Insulation Labor Costs

The average national cost to insulate a basem*nt ranges from $1,400 to $6,300, depending upon the size of the basem*nt and the type of insulation used. Labor costs can run between $0.25 to $0.50 per square foot to insulate a basem*nt.

DIY or Hire a Pro?

Insulating a basem*nt is and isn’t a DIY project. Installing rigid foam insulation or fiberglass batt insulation is more of a DIY project than blown-in insulation or spray foam insulation because both blown-in insulation and spray foam insulation require special tools and expertise to do so perfectly.

Insulating a basem*nt properly is important because a poorly insulated basem*nt can lead to water issues and more expensive problems down the road.