Roofing & Reroofing

Roofing

There are many different types of insulation materials to choose from when applying a commercial roof or reroofing an existing structure. The function of roof insulation is to insulate the building against heat flow in and out, and also providing a smooth, dry, and clean and substrate for the roof membrane.

Proper insulation is necessary for energy efficiency, condensation control and, in some systems, structural integrity against uplift pressure.

Extruded polystyrene foam (XPS) insulation has a combination of properties that make it a strong and efficient insulating material. Its proven resistance to moisture; reliable strength and durability–even without a facer or coverboard; and stable long-term R-Value make it a top insulating material for commercial, industrial and residential structures.

Benefits of using XPS in roof applications also include positive environmental attributes, such as long-term durability and recyclability—making XPS an ideal choice when reroofing a building.

Additionally, in direct-to-steel deck applications, cost savings are achieved because in many conditions a thermal barrier is not required between the insulation and the metal deck.

Selecting XPS as your conventional roofing system insulation offers exceptional performance in plaza and protected membrane roofing assemblies (PMRA). XPS provides:

• Excellent moisture resistance and stable long-term R-value
• Extending the life of assembly by protecting the membrane from ultraviolet (UV) degradation
• Protection of the membrane against weathering, physical abuse and damage
• Maintaining the membrane at a relatively constant temperature, thus minimizing effects of freeze-thaw cycling and excessive heat
• Reduced installation, material and repair cost
• Easy removal and re-installation of ballast and insulation

Check with the manufacturer for more specific information on various roof applications employing the use of XPS.

Reroofing

Reroofing is an important application for commercial contractors.

Roofing recover is a process used in many commercial building reroofing projects. In roof recover, the existing roofing membrane is left its place. Any large pieces of debris are removed, a recover board is typically mechanically attached through the structural deck and a new roofing membrane is installed on top of the recover board.

This process has many benefits. From an environmental standpoint, leaving the existing membrane in place reduces the amount of waste material sent to the landfill. It also can increase the energy efficiency of the building by adding additional insulation. Roof recover reduces the disruption to normal building operations since no tear-off is required.

One concern with this process is that the existing roofing system may likely contain some amount of moisture, since the roof is not normally replaced unless there has been a history of roof leaks.

Extruded polystyrene foam (XPS) makes an ideal roofing recover product. XPS manufacturers offer a wide variety of products for use in this application, including fan-fold products specifically designed for quick installation. The fanfold products have a variety of facers designed to work with specific membrane types. They also offer board-stock products designed for use under all single-ply roofing membrane systems.