Insulating a basement can save hundreds of dollars per year in fuel costs. With a wide variety of options to choose from, a homeowner should weigh both their needs and the specific details of their property carefully, in order to make the most informed and appropriate choice for insulating their home. Local building codes and requirements for the R-value of insulation must also be taken into account before any insulation installation commences.
Insulation is graded by its ability to retain heat. This grade is called its “R-value” and different regions of the country will have different R-value requirements written into the building code. Finding the appropriate R-value for your region is imperative, not only for optimal heating of the home in that particular climate, but also for the installation job to pass a home inspection.
Basement walls can be insulated from the exterior or the interior. Insulating from the exterior is sometimes impractical for an existing structure and is more appropriate for homes still under construction. Retrofitting a home with exterior insulation can also be quite costly. Most exterior insulation options can invite insect infestation. In addition, if the surrounding soil happens to contain radon gas, the homeowner will need to install a radon mitigation system.
In spite of the drawbacks, there are also advantages to insulating exterior walls. Insulation applied to the exterior will not take up valuable square footage inside the basement. It will also help to serve as a moisture barrier, protecting the interior space from leaking or weeping walls. It may also protect the home`s foundation from the rigorous effects of freezing and thawing in extreme climates.
Most homeowners find insulating their interior basement walls to be the most cost-effective option. There are also far more insulation materials to choose from. While insulating the basement ceiling is also a good way to improve a home`s thermal value, insulating the walls can be cheaper because walls have less overall square footage, while still providing the same amount of thermal value.
Typically, basement interior walls are insulated with blanket insulation. This can be woven from substances such as fiberglass and have a variety of different backing materials, such as paper or foil. This is the most common form of insulation, as well as being the cheapest at $.75 per square foot. It can be trimmed easily and installation can be managed by non-professionals.
Slightly more expensive is foam board insulation, at around $1.00 per square foot. Thin sheets of polyurethane or polystyrene can be quickly mounted to walls, providing excellent insulation properties with less space than blanket insulation. Another option is to use loose-fill insulation. At $.50 per square foot, it is cheap, but the labor cost can run up to $5.00 per square foot, making it the most expensive of the three. Small pellets of foam or fiber are poured or blown into a space between the foundation and the drywall. The main advantage of loose-fill insulation is that it will conform to any shape and is the most efficient of the different insulation types.
Installing some forms of interior insulation is a job requiring few specialized skills or tools. Installation of blanket or foam board insulation requires little more than a staple gun or a drill and masonry screws. The combined factors of being low-cost and using non-specialized labor make installation of insulation in a basement an attractive and practical DIY project for many homeowners. Not only will it pay for itself over time, but it will also provide a valuable selling point to prospective buyers.