Basement Rim Joist Insulation for Cold Floors

It is common to experience changes in the climate of your home when the seasons change. As the cold air and snow arrive in Michigan, you may notice certain areas of your home being much warmer or colder than other areas. Varying room temperatures causing you to wear an extra layer or use a blanket might be a sign of air leaks or poor insulation in the walls, windows, and attics of your home. If you are grabbing for an extra pair of socks or pulling out your slippers due to frigid floors, you may have a different insulation problem. The cold floors are a good indication of poor insulation or sealing in the basement or floor foundation of your home.

Typically, the parts of the floor structure that lack insulation causing these issues, are the rim joists, but there is a simple solution. Keep reading to learn all about basement rim joist insulation and what it can do for your house.

Will insulating my rim joists make my house warmer?

If you want to keep your house and floors warmer, start with the rim joist. Joists are the primary structure of the floor frame of a house and are supported on the ends by the foundation of the house. Rim joists are located at the top of your basement walls. They usually look like wooden squares going around the perimeter of your basement. The main purpose of a rim joist is to support the weight of the floor resting on the joists.

Without insulation, the only barrier between the inside of your home and the outside is the siding or brick. The rim joist typically spans around the perimeter of your home near ground level and it often has large areas where utilities like gas and electric will enter. The rim joists are often under-insulated or neglected, especially in older homes, which lead to cold floors because of energy loss and drafts entering through the basement sill plate. By properly insulating and air sealing your basement rim joists, your home will be able to keep heat in and unwanted drafts out.

How effective is basement rim joist insulation?

One of the easiest ways to increase the comfort of your home and improve its energy efficiency is through basement rim joist insulation. This home improvement will seal and insulate the rim joists of your floor structure to eliminate air leaks and drafts that cause cold floors. By insulating these areas, the energy is forced to stay in your home, creating an even temperature year-round.

It is very common for rim joist insulation to be accompanied by air sealing and attic insulation. This is because, if energy is unable to escape through the basement, it is pushed upwards where it can escape out of the attic if it is not properly sealed. You will yield the best results from basement rim joist insulation by insuring both your basement and attic are properly sealed and insulated.

Why shouldn’t fiberglass be used to insulate basement rim joists?

At this time, it is recommended to use only air-impermeable insulation for rim joists. Fiberglass batts have long been used as the insulation for rim joists but it is no longer appropriate. Fiberglass batts are not up to the accepted standard of the rim joist insulation practice because the material is permeable allowing outside elements to contact the rim joist and enter your home. Without impermeable insulation, condensation will reach the rim joists and can cause mold and deterioration which will directly impact the foundation of your house.

Why is spray foam the best choice for basement rim joist insulation?

Spray foam and rigid foam are the two types of air-impermeable insulation available. At Ecotelligent Homes, we use spray foam insulation for basement rim joists because not only does this material insulate, it expands to fill all the gaps and difficult to access areas of the rim joist. Our closed-cell spray foam is an air barrier and thermal barrier, meaning it will keep energy in and drafts out. On top of that, it is waterproof making it the best option for basements where water and exterior damage is most likely to occur.

Signs your home needs basement rim joist insulation

One of the most common signs of needing basement rim joist insulation is cold floors on the main level of your home. Many homeowners think they have to live in this discomfort because of where their house is located in relation to the sun, the age of their home, or the climate in their area, but that is not the case. If your floors feel abnormally cold, you may need basement rim joist insulation.

Ultimately, the best way to determine if you need basement rim joist insulation is through a comprehensive energy audit. An Ecotelligent Homes Energy Consultant would evaluate the current status of your basement rim joist insulation, identify where energy is escaping, and what is causing cold floors or uncomfortable temperatures. Then, they will be able to set up a plan for proper insulation and sealing.

Is it worth it to insulate my rim joists?

The biggest advantage of rim joist insulation is the increase of comfort and even temperatures throughout a home. Without proper basement rim joist insulation, homeowners in Michigan and cold winter climates experience dramatic discomfort during the peak of the season. Once these homes are properly insulated and sealed, homeowners no longer have to endure cold floors in the winter.

Insulating your rim joists will also increase your home’s energy efficiency. By insulating and sealing problematic areas, such as the basement joists, your heating and cooling system won’t have to work overtime to stay at a consistent temperature. If your home temperature is more stable after air leaks are insulated, you will be able to live more comfortably while wasting less energy.

Another perk of basement rim joist insulation and air sealing is eliminating the small holes where bugs and critters can enter your home. The holes that are allowing cold air to enter your home are also an entrance point for mice looking to escape the cold winter air and snow. Properly insulating your rim joists will make it more difficult for unwanted visitors to enter your home in the winter.

If you are ready to get rid of your cold floors or are interested in learning more about basement rim joist insulation, contact Ecotelligent Homes today!