Low and Steep Slope Roofing System Index

Read below to learn all about the different types of residential and commercial roofing systems we install at Multifacet as the Puget Sound's most trusted roofing contractor.

Types of Commercial, Flat, Low Slope Roofing Systems

Built- Up Roofing Systems

Built-up roofing systems (BUR) consists of layers or plies of roofing felts, between which asphalt or bitumen is applied. Built-up roofing is one of the oldest and most durable systems available. Its multiple layers provide extra protection and perform well in extreme weather conditions.  Built-up roofs are especially resistant to damage from wind, hail and snow. They are easy to repair and ideally suited for applications requiring a high level of redundancy.

Among the advantages of Built-up Roofing Systems:

  • BUR surfacing materials can be coated with paint or other reflective materials to reduce the effects of UV radiation.  These coatings provide the additional benefit of reducing cooling and heating costs.

Modified Bitumen Roofing Systems (Torch Down)

Modified Bitumen systems consist of asphalt with modifiers added to give it durability.  These are either one- two- (most common), or three ply-systems.   They are factory manufactured and combine the redundancy of built up roofing with the ease of application of a single-ply system.
Modified Bitumen Systems are of two kinds:

  • SBS (Styrene Butadiene Styrene) systems areusually installed with hot asphalts or cold adhesives.
  • APP (Atactic Polypropylene) systems in almost every case are installed using the torch method.

Both SBS and APP systems can be reinforced either with glass or with polyester.  Among the advantages these systems offer:

  • The rolls of these roofing materials are factory-manufactured, ensuring quality control.
  • These systems are well-suited to expand or contract with the movement of the building they protect.
  • The modified bitumen roof systems can be finished with a variety of surfaces that enhance their resistance to oxidation and damage from UV rays.

Single Ply Roofing Systems

Single-Ply roofing systems are composed of insulation, a single ply membrane, flashings, and adhesive.  TPO, EPDM, and PVC the three most common types of single-ply membrane systems.  Since they consist only of a single layer of roofing over insulation, these popular systems are lightweight, making them an ideal choice for retrofits. 

TPO Roofing Systems (ThermoPlastic Olefin) combine the long-term durability rubber provides with the security of hot air welded seams. TPO’s advantages include:

  • TPO roofing systems are the most environmentally friendly of the single-ply systems.
  • They produce no dioxins or chlorine.
  • Membranes come in varying thicknesses to meet your specific requirements and are available in varying roll widths.

EPDM (Ethlyene Propylene Diene Terpolymer) is a stable roofing alternative that withstands extremes of temperature and expands and contracts with the building.

  • EPDM systems require minimal maintenance and are resistant to UV radiation and ozone.
  • EDPM technology has proven effective for more than 30 years.

PVC Roofing Systems are among the easiest single-ply roofing membranes to install and heat-weld together.  Among the advantages PVC systems provide:

  • These systems are able to resist various chemical effluents.
  • They provide superior resistance to punctures and tears.
  • PVC systems are especially suited for roofs that are exposed to concentrations of grease, oils and many kinds of fuels.
  • In areas where acid rain or other forms of acidic outflow is a problem, PVC roofs are the preferred solution.

Tapered Roof Insulation Systems

The goal of tapered roof insulation systems is to reduce or eliminate the amount of ponding/standing water on the membrane when the existing roof deck does not provide adequate slope. Draining water in a timely and efficient manner minimizes the adverse effects that ponding or standing water has on completed roof membranes. A properly designed tapered roof insulation system not only provides the positive drainage needed but also helps extend the life of the roof membrane.
Such systems, properly installed, can be a major factor in extending the useful life of a roofing system and help prevent any structural damage that an insufficient roof slope can cause.

Types of Residential, Steep Slope Roofing Systems

Metal Roofing Systems

Metal roof systems fall into three general steep-slope roofing applications:

  • Architectural metal panel roof systems shed water and are intended for use on steep-slope roofs.
  • Structural metal panel roof systems are used on both low- and steep-slope roofs. They are especially appropriate for low-slope roofs because of their hydrostatic, or water barrier, characteristics.
  • Metal shingle panel systems provide the same hydrostatic characteristics, and are often preferred for smaller roof areas.

Metal roofing is a preferred alternative for sloped roofs, especially when durability and weather resistance are primary concerns.  The different systems are engineered not only to accommodate the slope of a structure’s roof, but to provide pleasing aesthetics, since these roofs are almost always visible to people at street level.

Shake Roofing Systems

Definition of cedar: any of a genus (Cedrus) of wide spreading coniferous trees of the pine family, having clusters of needlelike leaves, cones, and durable wood with a characteristic fragrance.The natural properties of cedar shingles and shakes make them the perfect choice for roofing material. Their resistance to decay, moisture and insects keep them vibrant for decades without needing maintenance. Other major benefits of cedar include high impact resistance, the ability to withstand 245 mph. winds, and they are a renewable resource. Over the hundreds of years that cedar shingles and shakes have been installed, the product has remained unchanged, it's still cedar.

Asphalt Shingle Roofing Systems

It's no secret asphalt looks great on your roof. But asphalt roofing looks even better when you stack it up against the competition! Metal, tile, slate, and wood. None of these materials can match the wide array of benefits only asphalt roofing provides. Whether it's superb colors and beautiful styles you're looking for, or unparalleled durability and performance, the bottom line is you simply won't find all these features in a single material... unless it's asphalt.

Solar Roofing Systems


Green Roofing Systems