Benefits of Commercial Roofing Vapour Retarders for Your Building and Tenants
Water vapour will naturally diffuse or move through various building materials, including the components of a roof, from high-pressure to low-pressure areas; for example, in the winter, warm water vapour from inside a building will move through the roof assembly to the cold and dry outside air, while the opposite occurs during the summer heat/humidity.
Unfortunately, this moist vapour can become trapped in cavities and spaces between the building’s interior and the exterior of its roof, causing an accumulation of condensation. This moisture build-up can, in turn, have several detrimental effects, including:
- Decreased thermal efficiency
- Decay of wood-based components
- Corrosion of steel structural members
- Respiratory problems due to mold growth
To help in preventing these circumstances from occurring in your commercial building, in particular to your roofing and/or to your occupants, you would be well-advised to ensure that adequate vapour retarders are installed.
Essentially, vapour retarders are thin sheets of material designed to inhibit/impede the flow of moisture through a roof (or a wall) assembly and protect it against condensation-related damage; this can be especially important for a flat roof, where its entire surface is often exposed to the elements on a continual basis. When properly installed, vapour retarders can also serve as air barriers that minimize the flow or movement of moist air into insulated spaces or cavities under the roof during the cold winter season.
Several types of materials are commonly used in commercial roofing vapour retarders:
- Class 1 – least penetrable (impermeable)
- Sheet metal
- Rubber membrane
- Polyethylene sheeting
- Class 2 – semi-penetrable
- Bitumen-coated kraft paper
- 30-pound asphalt-coated paper
- Expanded or extruded polystyrene
- Class 3 – most penetrable
- Board lumber
- Gypsum board
- Brick and concrete block
- 15-pound asphalt-coated paper
- Insulation (cellulose; spray foam; loose-filled fiberglass)
Installing new vapour retarders or upgrading the existing roof vapour barrier material of your commercial building can have a rather positive impact on preserving the structural integrity of the roofing as well as improving your energy efficiency and indoor air quality.
Related Post: Commercial Flat Roofing Maintenance
Vapour Retarder Installation Services from Commercial Flat Roofing Specialists
In order to optimize the benefits that can be gained from vapour retarders, you will need to ensure that the right choice of material is made for your particular building/business, and that qualified professionals are contracted to perform the installation.
The specialists at Can-Sky Roofing have the experience and skills to provide efficient and effective vapour retarder installation services for all types of commercial/flat roofing; our staff can make suggestions and recommendations on the best vapour retarders to install based on several factors that property owners might not readily take into consideration; these factors can include but are certainly not limited to:
- Average outside temperatures
- Interior relative humidity levels
- How often the doors are opened
- How long the doors are left open
- Composition of the building envelope
For additional information about our commercial/flat roofing vapour retarder installation services, call the specialists at Can-Sky Roofing today at 647-691-0487 or contact us for a no-obligation consultation and a free estimate.