By Sadia Badhon
A new insulation application method, where all the spray foam is done from the inside of a large building, can save building owners both time and money. With this method, there is no need to work outside in the cold Canadian weather.
When thinking about the insulation application process on the exterior of the building, with scaffoldings and weather conditions, it is more difficult and costlier in the winter months than in the heat of summer. First off, when applying building envelope products in cold temperatures, while there are many steps one can take to ensure the successful application of the product, the job simply takes longer. Climatic conditions are an important factor that must be considered when selecting building materials. This is not the case with spray foam and this new application process where it is all installed from within the building.
In an exclusive interview, Maxime Duzyk, director of building science and engineering, North America, with Huntsman Building Solutions, spoke to Construction Canada about the new insulation application method.
Tell us more about this new method of insulation application. How is it done?
Duzyk: This new method of insulation is a new way of building. This application method is done in combination with closed-cell spray-applied foam (ccSPF), where the wall is composed of regular steel studs, but instead of installing the exterior sheeting directly on the steel studs, a Z-girt is installed horizontally on the studs and then the sheeting is installed on top of the Z-girts. This allows for a space between the studs and the sheeting, which facilitates the foam to insulate between the two, thus removing the thermal bridge. It is like the insulation is on the exterior of the building, but it is actually applied from the interior.
The ccSPF along with this new application method removes the need for the spray foam applicator to work outside, leaving other building envelope trades to work faster on the exterior of the building and to complete their part of the project. It saves time spent onsite, is more economical, and provides a higher building envelope quality and durability.
The spray foam used in the interior application replaces four materials including the exterior insulation, the full-surface membrane, fibreglass insulation in the cavity, and the poly. Spray foam acts as an air barrier, vapour barrier, and insulation, so it can replace all these materials. It is not affected by water and is also mould resistant.
What are some of the other benefits of this application method?
Duzyk: As mentioned, every step of winter construction takes longer. Materials will be exposed to rain, snow, and wind. The adhesion of some products will be diminished in colder applications.
When it comes to winter building, there are so many considerations for project success. Temperatures must be constantly monitored. Substrates should have less than 19 per cent moisture content. There might be too much rain, wind, snow, or ice on the substrate. Since insulation products are often sensitive to water, the complete building needs to be watertight before installing the insulation, thus creating delays in sequencing. The exterior air barrier should also be applied before the interior insulation and vapour barrier. Winter projects cost more time, labour, and money to install a building envelope than it does in the warmer months.