Spray foam roof install process:
We understand that our clients’ operations are critical and cannot be disrupted. Often, this is a contributing factor when SPF is specified for the project. This is true both during the installation and during the life of the roofing system. A main concern of building owners or tenants is construction down time and with SPF systems, there will be NO business interruption, and no bad odor such as tar.
Polyurethane foam can be applied over almost any substrate, which usually eliminates the added expense of tear-off. In most cases preparation simply involves cleaning and securing the roof surface. Preparation for Different Roofs include:
Installing the Sprayed Polyurethane Foam:
Polyurethane foam is sprayed onto the prepared roof surface in two-components that when mixed expand to approximately thirty-times their volume to form a seamless layer of rigid closed-cell foam. Within minutes this foam can be walked on and cures to 90 percent of its full strength in about four hours.
Because polyurethane foam adheres to most surfaces, horizontal, vertical, or overhead, it creates a fully-adhered, self-flashing, monolithic roof surface, with none of the critical failure points of most roof systems (seams and penetrating fasteners).
With an insulation value of R-6.7 per inch, polyurethane foam is the most efficient form of thermal insulation available on the market. The energy savings usually cover the cost of the roof system in a few years and by placing the insulation on the outside of the envelope, the foam reduces building expansion and contraction.
The thickness of the foam can be controlled to create positive drainage where ponding was previously a problem.
Installing the Protective Surface:
Next, protective surfacing, typically a spray applied elastomeric coating is applied. Protective Surfaces also include membranes, such as fleece-backed single-ply membrane. The purpose of surfacing is to provide weatherproofing, protect the foam from UV exposure, provide protection from mechanical damage, and assist with fire resistant characteristic of the roof system.
Various coatings used on SPF based roof systems include: Acrylic, Butyl Rubber, Hypalon, Silicone, Aromatic polyurethane Elastomer, Aliphatic Polyurethane Elastomer, Modified Polyurethane Elastomer. Coatings can be used for other purposes: inhibiting moisture vapor transmission, enhancing aesthetics, increasing impact and abrasion resistance, achieving flammability and code requirements.
Typical Protective Surface:
Installing the Coating Base coat:
Once the polyurethane cures, two layers of an elastomeric coating are applied to further protect the roof from ultraviolet light, weather, and normal wear. To ensure complete coverage of both coats, the base coat is a contrasting dark color.
Installing the Topcoat & Granules:
A light topcoat reduces thermal gain, and a layer of granules embedded in the top coat dramatically increase the durability against mechanical damage.