How Long Does Spray Foam Insulation Installation Take?

There are few home energy upgrades that are as quick and hassle-free as installing spray foam insulation in an attic or crawl space. Most jobs will take one to two days from start to finish.

Both closed-cell and open-cell spray foam insulation will dry and cure fast enough that your family can enjoy the benefits of insulation within hours.

Let’s break down the process and see how long each step takes.


1.   Get an estimate (Approx. 1 hour)


This is as simple as picking up the phone and asking a professional to come and evaluate your home. An estimator will be over to measure square footage and inspect the workspace. They will be looking at a variety of things as they assess the space:

  • Whether or not the old insulation needs to be removed
  • Availability of workspace (Will the workers need to be on their backs?)
  • What specific tools are required for the space to get the job done right?
  • What kind of ductwork needs to be worked around?


Usually within 24 hours, you will receive an estimate including costs of material and labor.


2.   Remove old insulation (4 – 24 hours)


Unless you are dealing with new construction, there is probably already some sort of insulation in the rafters. Most likely, it will be roll-out fiberglass insulation, which will need to be removed prior to installation.

A crew will arrive to remove, bag up, and haul away the insulation.

While it is possible to remove the old and install the new insulation in just a few hours, this is rare. Contractors often prefer to break the jobs up into two distinct projects with different crews.


3.   Installing spray foam (4 – 48 hours)


When the crew arrives in the morning, they will follow a series of steps to get you protected from the North Carolina sun in no time. Your house will be taken over for a short period as they:

  • Lay down protective covering on your floors
  • Hook up all equipment (air compressors, hoses, power cords) and prep their mixtures
  • Extend ladders to open hatches for crawl space access
  • Prep their workspace in the attic by laying down surfaces to stand and kneel on


Once the tools and mixture are set, a trained crew can spray a 1,300 square-foot attic in as little as 2-4 hours.

Spray foam hardens quickly. It is tacky and flat when initially sprayed. In a matter of minutes, the foam expands and begins to cure. The crew waits for one layer to expand just a bit and then makes multiple passes until the rafters are filled with hardened foam.

If there is any chance that the space will be finished with drywall in the future, then this is the time to cut out the extra, bulbous foam. Installers will use a  saw with a flexible blade to cut the foam so that it is flush. This can add an hour or two and raise the cost but is well worth it if the attic might become a bedroom someday.


4.     Drying and curing times (1 – 24 hours)


Within 5 minutes the foam itself is hard to the touch and will have lost most of its tackiness. It is considered fully cured after 24 – 48 hours hours.


So, How Long Does Spray Foam Insulation Installation Take?


From beginning to end, the actual spray foam installation process, including the removal of old insulation, can be as quick as 24 hours. However, it’s best to assume you will have workers at your home for two days so that you can plan accordingly. 


Schedule a free quote or give us a call at 844-MPI-FOAM. We’ll get a consultant out to your home ASAP to give you an estimate on how long it will take to install spray foam insulation in your home.


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