How Much Does Spray Foam Save on Heating and Cooling

Spray foam insulation is the most effective insulation types you can utilize to protect your home from heat or cold. Its properties act as an air sealant and insulator in one and its high R-value means it can be applied to the roof decking to slow the heat transfer into your home before it even enters the attic. Spray foam also saves you on your heating and cooling bills by allowing you to utilize a smaller HVAC system, eliminating the need to air seal the attic floor, and causing you fewer repairs on your HVAC system over its lifetime.  If you want to know how much spray foam insulation will save on your energy bills there are several factors you need to consider to get an accurate savings estimate.  The table below shows how much savings to expect from spray foam insulation for different applications.​

As longtime energy auditors for both APS and SRP, Green ID has experience with spray foam in all types of homes. The factors that influence how much spray foam insulation will save you on your energy bills depend on the following

​Age of Your Home

​Your home’s age will affect how much cost savings you see from spray foam insulation. The insulation codes have changes a lot over the past 50 years and newer homes with R30 insulation will see lower cost savings after installing spray foam than homes built in the 1970s that have 3-4 inches of insulation. That is because well-insulated homes will already be somewhat protected from the outside elements and their energy bills will be lower because their base level of insulation is already helping. Block homes built before 1990 have no insulation in the walls so injecting spray foam into the block walls is going to have a huge benefit compared to homes with block walls built after 1990.

How much will spray foam on the roof decking save? 

​Newer homes or well insulated homes will see around a 10-15% reduction in their heating and cooling costs compared to a 20-30% reduction for older homes with little existing insulation or homes with fiberglass batt insulation.

How much will spray foam in block walls save?  

​Homes built before 1990 with block walls will see a 15-25% reduction in their heating and cooling costs when spray foam is installed in walls that see more than 2 hours of direct sunlight.

Whether You Have a Single-story or Two-story Home

​Single story homes will benefit more from having spray foam than two story homes with typically double the attic square footage. Existing homes with vaulted ceilings and little attic space cannot be upgraded to spray foam over the vault because it’s impossible to access unless the drywall is removed.  For vaulted ceilings, an air barrier can be created between the vaulted ceiling and the accessible attic, creating a conditioned attic area with spray foam and an unconditioned attic without spray foam. The attic with less area to apply spray foam insulation will also have lower cost savings than 100% accessible attic spaces.

Whether the Existing Insulation Is Left in the Attic Or Removed 

​Homeowners will save more money on their utility bills when the existing insulation is removed from the attic floor. This is because insulation left on the attic floor with spray foam on the roof deck traps the heat inside the attic during the summer, causing the temperature to increase much higher than if no insulation is present on the attic floor.

The Climate

Homes in different climates can vary where heat loss and heat gain enter into the home, and then vary on how much energy can be saved with spray foam. For example, in Phoenix, despite our 118 degree summer days, the majority of our heat gain comes in through the windows!  Not the attic, not the walls… the windows. So it becomes impossible to save 30% on your total energy bills with spray foam on the roof decking when only 15% of your heat gain is coming from the attic space.  In Chicago, the walls are the greatest source of heat loss and so wall insulation is the best upgrade you can choose for spray foam. 

Deciding if Spray Foam is Right for You

​If you feel as though your home is perpetually losing you money due to inadequate insulation, we can help! By starting with a simple Energy Audit from Green ID, we will perform multiple tests to identify and recommend upgrades to your insulation and airflow. Depending on the factors outlines above, spray foam insulation may be the right next step for you. Installation can also be done safely and effectively so you can begin to breathe easier. Contact us today to get started.