Basement Insulation

Basements have been one of the important areas in homes. From being used as secret passages by people during war times to being used as a multipurpose room, the basement serves for a lot of reasons. It is always good to have extra space in the house for storing and other purposes. But these spaces need good maintenance too. Like every area of the house, the basement needs to be insulated too.  

Why is Basement Insulation important?

Insulating your basement is important because it protects the interior environment by maintaining the comfort level of homeowners. Like any other insulated area of your home, basement insulation proves efficient in saving you from expensive energy bills and makes your home more comfortable by balancing the thermal condition. An insulated basement is considered a conditioned space. The basement is usually more connected to other living areas in your home as compared to the outside. This makes it conditioned and makes the wall insulation in the basement compatible with the ceiling insulation. Basement insulation is a high performing structure that controls moisture, drainage or frost which are the common problems. 

“Basements are responsible for about 20% of the total heat loss.”

Air passes through basement windows and seeps through the cracks and the foundation wall. Some basements are dry and are prone to pests and termites. Basements that are used for storage purposes or function as living space need to be dry in order to avoid molds and other properties that harm the area. Basements are also used for groundwater and rainwater control. The basement needs to be insulated in order to reduce the effect of condensation and elevate humidity. Insulating basements can be fruitful in terms of saving a lot of your efforts. 

Basement Insulation- Inside and Outside

Generally, outside basement insulation is considered as a better option. Insulating on the inside is also important for various reasons, including economical. A combination of both inside and outside insulation works the best and is required for basements. Inside the basement, insulation involves the installation of rigid insulation board, wooden-frame wall and other combinations. In this case, you need to take in to account several factors like moisture problems, cost and space to use. While the outside basement insulation involves excavating the foundation, installing insulation along with waterproofing. 

Exterior Basement Insulation Interior Basement Insulation
Exterior walls are easier to insulate and problems like cracks, moisture or eroded mortar can be easily spotted and corrected. Interior insulation is easier and cheaper considering full wall with high R-values.
The interior of the house stays undisturbed and there is no loss in inside space. Any time of the year is favourable for this insulation.
Frost cannot penetrate to the footings and hence freeze-thaw problems are prevented. It is also a ‘do-it-yourself’ job. 
Foundation mass is within the insulated portion that evens the temperature. Insulating the inside of a basement does not lead to any kind of disturbance to the landscaping or driveway. 

Benefits of Insulating Basement Walls, Floors and Ceilings

Area Benefit Insulation R-Value
  • Non-water sensitive insulation should be used for basement walls. This prevents the interior from air contact with the cold basement surface.
  • To avoid the structural elements of the wall being cold, it is important to construct the interior insulation as airtight as possible.
Foam based insulation works the best in basement walls.

Spray polyurethane foam (SPUF) has been favourable insulation for the walls for its better performance. It ensures total protection when sprayed directly into the walls.

R-11 to R-13 is the best for basement walls as recommended by the Model Energy Code.
  • It is preferable to insulate underneath the basement floor slabs. 
  • It shows a significant effect on comfort and prevents moisture damage and condensation in general.
Rigid insulation works the best for basement floors. 

Rigid foam insulation, 1 ½ inch thick works the best for floors as it provides an efficient thermal break between the concrete and floors.

R-10 to R-20 is the range of r-value for basement floor insulation prescribed.
  • Basement ceiling can be easily insulated between the floor joists. 
  • Keeps the heat upstairs in the living space and insulates water pipes or cooling ducts as well. 
Fiberglass batts or blankets work the best for the ceilings. R-12 is highly recommended
Types of Basement Insulation

Loose-fill Insulation

Loose-fill insulation consists of fiberglass or mineral wool which is recycled materials. It is effective and cost-effective.

Spray Foam Insulation

Spray foam is considered the best for basements. It is effective for basements and requires no extra renovation. Spray foam has potential high R-value and is water-resistant. It seals the basement walls well and prevents the loss of hot or cold air. Spray foam saves a lot of energy by reducing energy consumption which gives you less expensive energy bills.

Foam Boards

Foam boards are also effective basement insulation for they decrease the heat flow and work as fire-resistant.  Foam board insulation is also water-resistant which prevents moisture build-up and mold growth. Also, foam board materials don’t need a replacement like other insulation materials.

Blanket Insulation

Blanket sheets or cotton blankets are insulation with the advantage of low cost and wide coverage. It is also sound-proofing and durable. 

Benefits of Insulating Basement

“Fifty per cent of heat loss can possibly occur in basements.”International Association of Certified Home Inspectors

Basements with gaps, cracks and poor insulation allow a good amount of warmth to escape from the home. Winter times can have an adverse effect on your home especially due to uninsulated or poorly insulated walls give impetus to uncomfortable conditions in the basement. It also makes the top floor harshly cold.  Insulating basement can enhance comfort and reduce heating costs. Insulated basements lock more heat on the inside and keep the cold air outside. Insulation enhances the air quality too. One of the major benefits of insulating basement is that it controls moisture resulted due to condensation. Condensation may cause damage to your basement. Using insulation vapour barriers can control moisture and prevent mold growth. 

As basements are underground or are directly in contact with the earth, there are chances that ground moisture seeps through the foundation wall. SPF foam insulation can help to prevent moisture. Whereas for the exterior wall, fiberglass insulation ensures the vapour barrier meets the desired requirements by local code. For basement insulation, almost any type of insulation can be used. Considering the suitable one according to the preferences of homeowners or professional insulation contractors is also necessary. Basement insulation prevents the threat of insect infest

R-value for Basement Insulation

R-value or thermal condition is important when it comes to insulation. The higher the r-value the better is the performance of the insulation. Basement walls have to be insulated well. Preferably, a minimum of R-10 is the value for continuous insulation and R-13 is for framing cavity insulation. 

Professional Basement Insulation with Celluloseman

Our professional team at Celluloseman are well-trained for insulation installation. Basement insulation is done with special equipment and other precautions. Our experts check the conditions of the basement. Along with insulation installation our experts suggest the right type of insulation to homeowners. We care for the safety of our clients and their homes. We make sure that we leave the home in a better condition and make the best use of our technical team and equipment. For more information about basement insulation and other services contact Celluloseman. 


R-value is important as it decides the efficiency of insulation. Higher the value, better the performance. For basement walls, R-10 as the minimum value for foam plastic or continuous insulation to R-13 for framing cavity insulation is required.  Building codes today vary from region to state. It also varies in different climate zones.  Due to the difference in these codes, r-value of your insulation may differ between R-5 to R-10. Mostly in Canadian cold climate zones, R-20 is recommended. Seeking professional help for r-value and the right insulation is required and preferable. 

An insulated and improved basement results in sustainable homes with less energy consumption. For the insulation to work efficiently and provide adequate thermal resistance, there are some factors to be considered and assessed. Some of the best practices include:

  • Moisture management needs to be done for basements. Choose moisture-resistant insulation. 
  • Insect and pest management must be addressed. Termites do not eat insulations like foams and fiberglass but there are chances of them to seep through insulation materials. Along with termite shields, some insulation materials like XPS foam boards can be incorporated.
  • Make sure that before and after insulating your basement, you assess combustion safety.
  • Avoid using a vapour barrier in the wall. It can trap the moisture and lead to mildew or mold growth. 
  • Use heavy plastic sheeting for subslab insulation as it will keep the floor warm and reduce condensation in warm weather.
  • Be careful with fiberglass installation, where and how it is done and ensure that there is no prolonged exposure to moisture or humid surfaces. 

According to Ontario’s Building Code, Basements are one of the major sources of heat loss. It is beneficial to insulate your basement for full performance and thus it is worth it. Basement insulation keeps the basement temperature warm during winter and cool during summer. Basement insulation helps control moisture which is a common occurrence as the basement comes into contact with the earth. It prevents moisture build-up in summer resulting due to heat and humidity. Insulation, in general, makes your residential or commercial structure healthy and comfortable. Basement insulation only increases the efficiency in the thermal condition of the house and helps it balance the temperature. 

Yes but some precautions need to be taken before using fiberglass insulation. Fiberglass insulation should be not directly applied to a concrete wall. There has to be some space between the wall and insulation. Consulting a professional insulation service team can be more beneficial in this case. Contact Celluloseman for more details and suggestions. 

According to research,  Spray foam is the best basement insulation for concrete walls. As spray foam is potent to acquire a higher R-value, it is considered best. It is also moisture resistant and required less thickness. Spray foam is known to fill the gaps and other spaces which makes the protection against moisture better and even air infiltration. Foam board is also a better option as it is water-resistant, thus prevents moisture build-up. It also controls mold growth. Foam board insulation can also be durable and need not be replaced over time. 

Basement  insulation vapour barrier is usually used in constructing buildings as it resists and prevents moisture from seeping through structures. Mostly, water vapour causes condensation. It is a natural occurrence caused by natural processes like a drastic difference in temperature around the unheated spaces like basements and other heated ones. Condensation results in water formation between walls or floors and damages the structure. To avoid this situation, basement insulation barriers are used. It is a better practice to use an insulation vapour barrier, especially in the basement as it has more chances of being prone to moisture due to direct contact with the earth. 

Get In Touch for Basement Insulation

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