Roof Types

Below is a list of definitions of roof product types.

Built-up Roofing (includes asphalt and coal tar pitch): Built-up Roofing (BUR) consists of built-up layers of coated asphalt and insulation applied on site and can be covered with a capsheet (or surfacing material). The “cool” products found in this category refer to the properties of the capsheet.

• Foam Roof Systems: Foam systems can also be divided into the field-applied and factory-applied categories.  Field-applied foam systems are similar to field-applied coatings, as they are sprayed on in liquid form and harden as they set on top of the roof.  Factory-applied foam systems are formed into rigid panels and coated with a reflective coating.  The foam usually give the roof system additional insulation properties.

• Metal: Metal roofing products can be shaped to look like shingles, or shakes, or to fit unique curvatures, in addition to a typical “standing seam” configuration.  They come in a variety of textures and colors, including some darker “cool” colors with special additives that allow these dark colors to achieve significantly greater reflectance than previous versions of the same product. 

• Modified Bitumen: Modified bitumen is bitumen (asphalt or tar) modified with plastic and layered with reinforcing materials then topped with a surfacing material.  Like BURs, the radiative properties of modified bitumen (mod bit for short) are determined by the surfacing material. 

• Other: This is where a product does not fit anywhere else. For example, we have a roof surfacing system, a rubber membrane, stucco, roll roofing and a few others.

• Roof Coatings:  Roof coatings can be divided into two categories: field-applied and factory-applied.  Field-applied coatings are applied directly onto the roof surface, either on a new roof assembly or over an existing roof surface (and can be applied over top of just about anything, so long as the right coating is selected). Factory-applied coatings are applied at the factory prior to distribution.  Examples of factory-applied coatings include coatings applied to metal and glazes that are applied to tiles.

• Shingles, Slate, or Tile: All of these products types use the same concept, where pieces fit together to form a roof. Asphalt shingles are fairly common for residential roofing applications, probably because they are relatively inexpensive and simple to install. Slate and tile products also come in a wide variety of colors, shapes and textures, and, because of their heavy mass, they have thermal properties that may yield additional energy savings beyond their reflectance and emittance properties.

• Single-Ply:  Single-ply roofing is a pre-fabricated sheet of rubber polymers. Single-ply roofing is laid down in a single layer over a low or steep-sloped roof. The single-ply membrane can be loose-laid and weighted down with ballast or pavers or firmly set on the roof and attached with mechanical fasteners or adhesives. There are two main types of single-ply materials:

• Single-Ply-Thermoset (includes EPDM, Hypalon): Thermosets are materials that can not be hot-air welded because it changes their physical characteristics.  Instead, tape or a contact cement to seal the seams.

• Single-Ply–Thermoplastic (includes TPO, PVC, etc.): Single-Ply-Thermoplastic is a flexible sheet membrane which consists of compounded plastic polymers.  When heat is applied onto the surface, the single ply-thermoplastic seams are melded together making the material seamless and effective. Most thermoplastics are manufactured to include a reinforcement layer (usually polyester or fiberglass) for extra durability and strength.  There are various types of single-ply-thermoplastic such as PVC & TPO.  PVC (polyvinyl chloride) is a synthetic polymer prepared from vinyl chloride. It tends to be more expensive than TPO, but is well known for long-term performance and is naturally fire-retardant. TPO (thermoplastic polyolefin) is a blend of polymers that can contain flame-retardants or UV absorbers.