There are a couple of things about spray foam insulation that it is a better choice to other types of insulation when it comes to insulating your house. The comparison is done based on a couple of factors such as cost, ease of use or implementation, operational cost, r-value, effectiveness and materials. To cut long story short, the following points explain some advantages of spray foam insulation over other insulation types.
The foam material in spray foam insulation can be used as an insulating and air sealing product for residential wall and ceiling cavities which makes it easy to completely fill wall cavities with insulation and to perform air sealing in a single installation step. Therefore, it is as if you are getting double benefits by doing a single step.
Since the foam material acts as a wind and air barrier agent, spray foam insulation often eliminates the need for separate air-tightness detailing which can increase energy efficiency and allow downsizing of the heating and cooling system equipment. You save not only energy cost in terms of less electricity usage but also the cost of purchasing large heating and cooling equipment.
Best of all, sprayed foam insulation does not shrink, sag, settle, or biodegrade which makes it one of the longest lasting insulation materials. I don’t have the information on how long it will last before the next insulation step is needed but my best guess is as long as your house is still standing and intact, you don’t have to do the spraying once it’s there in the first place.
Most foam insulation products have a higher R-value per inch than fiberglass batt insulation. Polyurethane foam insulation has about twice the R-value per inch of traditional batt insulation, making it more energy efficient in smaller space. This increases energy efficiency by allowing downsizing of the heating and cooling system equipment. Thus, you save cost in terms of less energy usage with smaller equipment.
Spray foam insulation is ideal for filling small spaces—such as window jambs, small stud bays, rim joist areas, and for sealing around electrical boxes and other penetrations—where cutting fiberglass batt insulation to fit can be difficult and labor-intensive.
Even though the installation of spray foam insulation requires a skilled installer, I bet that this technology is readily available in most major cities in the US and around the world. Moreover, most foam insulation products and spray equipment are readily available and can be purchased or rented in most major hardware stores such as home depot.
In terms of cost, spray foam insulation can be costly during the initial installation step which runs about $1.25 to $2.25 per square foot compared to fiberglass batt which only runs about $0.70 per square foot for R-19. But sprayed foam forms both an insulation and an air barrier in a single installation step and this makes it cost competitive compared to batt insulation because it eliminates the steps for air-tightness detailing (such as caulking, applying housewrap and vapor barrier, and taping joints). As a result, it also reduces construction time and the number of specialized contractors. Moreover, the process of installing spray foam insulation is relatively fast and that can result in even lower labor costs. Watch the video on spray foam insulation installation process at this article, Spray Foam Insulation.
Lastly, many spray foam materials are environmentally friendly. Most of them do not contain HCFCs that are harmful to Earth’s ozone layer, or off gas formaldehyde—a potentially harmful volatile organic compound.
In conclusion, since there are so many advantages of spray foam insulation, I don’t see any reason why you would not consider it in your renovation plan.
Related Home Insulation Guide