Below-Grade Continuous Insulation Solutions for Basements

Conditioned Crawl Space Basement


Below-grade areas, such as basements, face several challenges including choosing the right insulation. When improper insulation is used, a home faces excessive moisture issues, cold floor joists affecting the heating of the rooms above, and frozen pipes causing property damage.

The type of insulation you use in your basement needs to be able to deal with the challenges unique to below grade areas. Choosing the right basement insulation can improve energy efficiency within the home, as well as make the entire property more comfortable. Insulation specific to below-grade areas can make a big difference to the comfort and safety of a property.

The Problems and Solutions for Insulating Basements

Basements, from the way that they are built to the way that they are finished, present a lot of singular issues for the homeowner and the builder.

Areas that are below-grade tend to have higher moisture levels than areas that are at or above-grade. This can lead to the growth of mold and mildew inside the walls and even in some types of insulation. 

Basements are also notorious for having poor air flow because of a lack of windows or other types of ventilation. They also tend to be colder year round, which means that if they aren’t properly insulated, they could be decreasing the energy efficiency of the entire structure.

In addition, insulating basements might be slightly different from other interior areas of the home since they are mostly underground and more susceptible to moisture infiltration. During construction, the exterior of the foundation can be insulated. This is a code requirement in many northern climate. However, if you are finishing a basement or retrofitting an interior there are insulation options.

Most builders are already familiar with using continuous insulation over the exterior of the building. Continuous insulation helps stop thermal bridging and air gaps, two of the biggest sources of energy loss through the walls of a home. Because the basement walls can be finished in several different ways, it’s typical for continuous insulation to be the best method of providing insulation to the area.

Continuous insulation on the interior of a basement helps prevent the same type of thermal bridging that can cause energy loss in the rest of the house. Insulating in this manner can also help address some of the moisture risks in basements as it can help prevent the condensation that can build up when there is an extreme temperature difference between the inside and outside walls. 

When you use continuous insulation throughout the interior of the basement, you improve the energy efficiency of the space, as well as the comfort levels of both the basement and the floor above. And because continuous insulation is often thinner than traditional interior insulation, it allows for a stud wall to be placed over and finished with interior drywall.

GreenGuard Insulation



When using continuous insulation in the basement, the ideal insulation will have both a high R-value and provide moisture protection. Kingspan’s GreenGuard XPS insulation boards meet both of these needs: They have an R-value of 5 per inch of thickness and offer protection against moisture infiltration when used in basements.

GreenGuard Type IV is a general purpose insulating board for wall and foundation applications that require a compressive strength of 25PSI. This lightweight insulation offers superior moisture protection and can be used in cavity walls and foundation applications.

If you need a stronger compressive strength, GreenGuard Type VI is also a general purpose insulating board but has a compressive strength of 40PSI. It can be used below slab to help provide better insulation to the floor, retains its insulating properties over time and can be used in all areas of the basement and with foundations.

Insulate Basements Properly

Continuous insulation used on the interior or exterior of the basement, like XPS insulation from GreenGuard, is the best choice for providing moisture management and energy efficiency to the area. Use the best insulation for basements to help create better, more comfortable and more energy efficient homes.

For more information on GreenGuard XPS insulation products, contact a Kingspan expert today.

Kingspan Insulation North America

Head Office & Sales Office – North America

Kingspan Insulation LLC

2100 Riveredge Parkway, Suite 175

Atlanta, Georgia



Call: +1(800) 241 4402