DIY spray foam insulation

Published On: January 14, 20159 Comments on DIY spray foam insulationTags: , Last Updated: February 13, 20246.3 min read

We are always searching new ways for improving insulation of our homes and new ways to save on heating and electricity bills in the process. All the traditional forms of insulation are expensive, they need skilled contractors to be applied and most importantly they are very hard to apply on existing home without tearing the house apart. DIY spray foam insulation is an alternative to traditional building insulation and you can apply it yourself without paying a contractor (did you know that only 50% of contractor price is the cost of materials?!).

heat circulation in house before and after insulation

Spray foam is a two-component mixture composed of isocyanate and polyol resin which comes together at the tip of a gun and forms an expanding foam that is sprayed onto roof tiles, concrete slabs, into wall cavities or through holes drilled in into a cavity of a finished wall.Polyurethane is the most common type of spray foam insulation. Polyurethane foam is sprayed directly onto wall and floor cavities as a liquid and quickly transforms into thick, hard foam insulation.

humidity circulation in house before and after insulation

Spray foam insulation is one of the most energy efficient products that a home owner can install. Around 40% of the homes energy is lost due to leakage of air through walls, doors and windows. Spray foam insulated buildings insulate as much as 50% better than buildings insulated with traditional insulation materials such as fiberglass. Also, spray foam takes up much less space than fiberglass or blown-in cellulose. Its thickness depends on where it’s applied, but it averages about three inches deep once installed. A home owner with a spray foam insulated home can lower his heating and cooling usage by 50-60%, severely cutting down on the energy bill. Spray foam insulation also acts as a water vapor barrier preventing moisture in the atmosphere to produce mold. The likelihood of rotting wood within the building is also reduced. A properly spray foam insulated home prevents the formation of molds and mold spores which lead to allergic reactions and often asthma. Apart from acting as an air and water vapor barrier, spray foam insulation can also act as a barrier to air-borne sound that is transmitted through the buildings roofs, floor and walls.

insulation comparison chart

There are two types of spray foam insulation, open cell spray foam and closed cell spray foam. Open cell foam insulation has tiny cells that are not closed. This uses less chemicals and so it is less expensive. It has a spongy appearance and is a good air barrier but it is not a good water vapor barrier. It has mostly indoor application. The closed cell foam insulation is more dense and has a more compact cell structure. It is a good air as well as water vapor barrier. It is used mostly in roofing and outdoor projects but can be used anywhere in the house. The closed cell insulation has the reputation of being expensive and that was the case when it came to the market but now its price is not much different than the price of open cell insulation.

The amount of heat that is retained within the house depends upon the thermal resistance to heat flow of the insulating material. Thermal resistance to heat flow is measured by R-value. Polyurethane has an R-value of R-7 to R-8 per inch of insulation in comparison to fiberglass having an R-value of R-2 to R-4. Polyurethane contains a high conductivity gas in its cell structure. The presence of this gas gives it a high resistance to heat flow. If you use thermal camera on a house with fiberglass insulation you will see gaps up to two inches wide where the heat from the house evaporates and on a house with spray foam insulation there is no gaps what so ever.

DIY spray foam insulation kit

Applying DIY spray foam insulation is not a job which need special knowledge. All you need to do is to buy a spray foam insulation kit, safety goggles and paint project respirator and you are ready to start. First check the temperature of the surface on which the foam is to be applied and the temperature of the foam tank and make sure that they are both at the same temperature of 60 to 80ºF. If the temperature of the tank is cool, then heat it with the bullet heated, if it is too hot then wait for the tank to cool down. Then you need to clean the surfaces and remove any dust or debris. Presence of dust and debris will prevent the foam from sticking properly. After that, use the wrench to attach the provided spray hose to the foam tank. Open the valves by turning them anticlockwise.

Always spray a thin layer of foam on the surface you want to insulate. After application of the first coat on all surfaces, let the foam dry for 20 to 30 minutes. During this time, the foam will expand and rise. Inspect the surfaces after 30 minutes and add extra foam if the layer is not thick enough. This completes the application process. The next step is to check for missed spots. Missed spots will result in poor insulated area. If you have discovered any missed spot, then respray that spot as you would normally do. After the job is done shut off the valves and detach the hose. Store the machine and the hose in some place where animals and children cannot reach. If you need to see how easy it is, check the video below.

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As you can see for yourself, it is not a difficult task at all and anyone can apply spray foam insulation without any professional help. It will save you at least 500$ on a contractor and it will pay off through heating and electricity bills in three years time, but the foam lasts for lifetime.

There are some who want to discourage people from installing spray foam insulation stating that it has a harmful effect on your health. That simply isn’t true, the foam fumes when installing it can be harmful and that is why we advised you to wear respirator when applying it, but when foam expands completely the fumes are gone forever and there is no health issues what so ever. There are even fire retardant polyurethane spray foams for those who says that polyurethane foam has toxic fumes when it burns. Don’t believe everything you read, spray foam insulation is completely safe, it saves a lot of money and you don’t have to pay anybody for installation. Spray foam insulation is considered to be a green product as it prevents wastage of energy by sealing out air leaks. In the United States, a building may be granted federal and state tax deductions for installing spray foam insulation.

DIY spray foam insulation is a great addition to your home in terms of energy saving as well as structural stability of the building. Spray foam insulation is recommended to families having individuals suffering from asthma as it prevents the access of moisture in your home, responsible for formation of molds and mold spores, which cause asthma attacks. We strongly suggest spray foam insulation for everybody who wants to save money on bills because it is a investment which will save you money your entire life.

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Leave A Comment

  1. Fred Dembek March 27, 2019 at 9:02 pm

    What are the negative aspects of spray foam… How about termites already under wood, can they be eliminated?
    ? Fire hazard, breathing the gas from foam melting? Roof damage from storm, construction, addition to building after foam has been applied? People allergic to foam gasses? Resale value, some buyers may like foam others may be very critical, foam is relatively new, hasn’t proven itself for a LONG period of time. Like solar there are some drawbacks for sale of homes. When I get the opportunity I’ve spoken to realestate folks and contractors and they agree foam has great advantages but will there be negative effects later. Look at electric heat in the north in the 1980’s it was presented as the future a real big deal, but failed terribly. I’ve really interested, ready to go for it, but want to hear the other side first.. Thanks, Fred

  2. Rachel August 16, 2018 at 12:36 am

    Great read. I now have a fair knowledge about open cell spray foam and closed cell spray foam. The article is quite detailed. Thanks.

  3. Albert Ebert April 27, 2018 at 6:12 am

    Proper insulation plays a helpful role in helping to create a better environment as well as reduce costs. It’s a comparatively typical article about insulation. Through the video and some important information, the blog will be very helpful to get proper insulation.

  4. Mitchell April 26, 2018 at 11:37 pm

    Interesting read… I’ve been looking to get more details on how spray foam insulation works. I’m enlightened. Thanks for sharing.

  5. Sam Fernandez April 26, 2018 at 6:31 pm

    For improving insulation system of our sweet home we’re spending more. Here effective ways I found what I’m searching and we will do this for our next. very helpful articles with vblog and well described step by step when it comes to home insulation.

  6. October 18, 2017 at 4:19 am

    Thi is some really good information about insulation. I liked that you pointed out that you should make sure you wear safety glasses and a mask when doing spray insulation. It is good to know that you need to be really safe when doing that installation. I need new insulation so that is good for me to know.

  7. Herman September 28, 2016 at 4:56 am

    Wow, love the article! The graphs and videos really helped me understand the difference between the different kinds of spray foams. I know it’s more expensive, but I think it will be worth it the next time I have the budget to upgrade my insulation.

  8. T.L. Thompson September 14, 2016 at 5:19 am

    We love the Closed Cell spray foam insulation we used in both our barns. When we built our house 3 yr ago our contractor advised on open cell because of cost and easier to work with. Closed cell expands a bunch, then there is a lot of clean up to remove foam that has expanded outside desired area. We know the closed cell helped keep pest out, mice won’t eat through it, and we have proved that with the 2 barns. So we did use Open Cell for the new house, inside walls and exterior wall and just everywhere imaginable. WELL BIG MISTAKE… wish we had demanded Closed Cell!! Being we live in the country, mice are just a part of life, BUT not in my house. Unfortunately, during construction, where workers are in and out and don’t always closed doors, mice did get in the house……and tunneled through the Open Cell spray foam behind my walls. To top that off, there was a very small place on my roof line, where roofers failed to seal completely….Honey bees found the spot, and they seriously ate the Open cell foam and took up residency and they ate about 6 sq ft of spay foam. Bees ate the foam clean off every area they wanted to build their hives. Needless to say, we have bees out now, cleaned up, replaced what wood we had to and are replacing with CLOSED CELL. Never again will we use Open Cell. But so love spray foam, insulation factor is great!

  9. Kael Drake December 17, 2015 at 10:39 pm

    I really like what you mentioned about how spray foam insulation is better at insulating your home than standard fiberglass insulation! You also said that it will be able to keep your home cool during the summer and warm during the winter, and also prevent mold growth in your home at the same time! We are in the process of building a home, and in the next few weeks we will need to decide what kind of insulation that we want installed. After reading your post, I think that it is more than clear that we should choose spray foam insulation! I’m going to talk with my builders as soon as possible so we can have this kind of insulation installed. Thank you for the information!

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