DIY Spray Foam Insulation Cost And Equipment Kits

While blown in attic insulation using materials like fiberglass and cellulose is by far the most common we have encountered ever better products like DYI spray foam insulation kits. In this article we want to outline what it involves, how it works, what the benefits are and how much it will cost. We should note at this stage that if you have already blown insulating material into your attic then spray foan is probably not a viable addition you should look into.

The reason for this is that in an attic space the foam needs to be sprayed directly onto the ceiling boards of the room underneath. This means that you need to remove any flooring and existing material. If you have insulating bats then this is a lot easier than the loose blown materials, which can be very messy and time consuming. If your blown cellulose of fibreglass is old and not very think then this may well be a good time to consider switching to a spray foam insulator.

General Improvements

The main benefit of using spray foam insulation in an attic space is that it provides an airtight seal and stops any kind of airflow. This increases your level of thermal barrier and also stops any damp and moisture build up which can be harmful as it can be a cause of mold. It also reduces the amount of allergens that float around your house, which is especially important if you have anyone in the household suffering from allergies to airborne materials.

Even the smallest cracks and gaps in the building structure can be fully sealed with foam. This is mainly because when the foam is pumped out through the nozzle it is still in a very liquid form. As the liquid dries it expands in all directions, thereby filling gaps and small spaces.

Fire Safety

A well planned and applied spray foam layer will also act as a fire retardant making it a lot more difficult for fire to spread into an attic space. Especially in places where there is easy airflow, tiny sparks can easily spread an cause a very rapid spread of fire.

While practically all spray foam materials these days are fire resistant it is very important to make sure you double check that before committing to a specific brand or service provider. Non fire resistant foam materials can in certain circumstances actually enhance the spread of a fire or be the source of a fire in the first place.


spray foam insulationBecause spray foam comes in many different materials it is very difficult to come up with one single spray foam insulation cost calculator. One thing we have to highlight first though. A lot of foam material used by contractors is quite toxic at the time that it is sprayed and still air born. This makes it less than an optimal solution as you would have to pay someone to do the job and vacate your home for several days.

One great product we have found is called Foam It Green which only requires a mask while the foam is being sprayed on. The spray foam equipment that they provide is practically fool proof and requires no experience at all. And also, the foam they sell will provide up to R-7 value per inch! That is an incredible amount but it does come at a price.

Combination With Blown Types

What we have worked out is that one of the best solutions you can come up with is to combine spray foam with the blow-in method into one project. This makes an attic airtight and very well insulated. Our cost calculation for this exercise will assume a standard attic space of 1000 square foot and that you are only planning to insulate the floor.

The home kit from Foam It Green covers a space of 1,200 square foot and includes the material, hose and gun including several nozzles and many extras that are very helpful. The price for this kit is $1,500, which is quite a bit more than the average blown insulation project. But we have already mentioned the benefits of doing this.

The great thing is that Foam It Green offers different packages that let you order just as much as you need. The cheapest way to cover 1,000 sqf is order two of their 602 packages, which will come in at just about $1,250.


Another advantage is that 1 inch of foam insulating material will provide R-7 value levels, which means that you can save a bit of money because you will not need as much bat or blown insulating material on top of that. Our best estimate for combining spray foam cost and blown types is that it will be coming in at $2,000 for both given a 1,000 square foot attic space. But savings from a proper attic project can be very significant whether you are heating or cooling your house.

Unlike blown insulation material, spray foam will stay exactly where you point the nozzle. This does mean you have to be sure that you are pointing in the right direction. Once it hardens it will not easily come away.

From a time investment point of view we would say that you should probably allow for 10 hours of work to prepare the attic, spray the foam and blow in fibreglass. It is probably best to do this over two days as it can be a very tiring job and being stuck behind a dust mask can become uncomfortable over time.


There are some disadvantages that we have encountered where people complained that they did not get the expected results. In the vast majority of cases this is due to the fact that either (a) not enough foam thickness was applied or (b) heat and air leakage spots were missed during the application process.

The first issue can be easily remedied by proper planning. The foam kits we recommend above will indicate the amount of space they will cover. If you finish you job and have some material left then somewhere you did not apply enough foam. One trick is spend a little bit of extra time planning.

When preparing your attic you use a thick marker or spray paint to make regular markings on the attic joists to indicate the exact depth you want to achieve. This way you can see exactly how high the foam is reaching. You can also use a needle to prove the thickness in regular intervals to ensure you are not applying it too thin.

Making sure that you do not miss certain cold spots is a bit more difficult. There are many very tight and difficult to access spaces where you will almost be guessing whether you have properly applied the material. We would always suggest identifying those areas during preparation and to start there, as it will allow you to build up a little extra material. Also, once you are finished with the project spend a little bit of time in the attic, ideally on a windy day to see and feel if you notice any obvious drafts.

Other Benefits

For the best possible results we would highly recommend the dual approach to insulating your attic. Spray foam is a really easy to handle material as long as it is made of low toxic materials when air born. With the majority of thermal exchange and loss happening vertically this is the one area where a little extra investment will go a long way. Once you factor in the ability to offset the cost against your federal income tax bill you will have already reduced the overall project cost quite significantly.

With energy savings on an average house estimated at $40 to $60 per month, such a project will have paid for itself within 3 years, so it really should be an easy decision to make. The work involved is simple and requires no hiring of expensive contractors. It also takes little time, saves money and adds huge amounts of comfort as well.

You should also take into consideration that a well insulated house will significantly add to the value of your house. If you talk to any real estate agent they will confirm that insulation and energy efficiency have become a significant selling point. At the same time, many home buyers do not want to buy a house and then have to plan for DIY jobs like this. Being able to provide this benefit will be a good selling point.