Business Building Roof Types Discussed by Bay Area Roof Repair Experts
Commercial roofing designs that are appropriate for low and flat slope buildings usually come in about five classifications:
- Metal Roofing
- Built Up Roofing
- Modified Bitumen Roofing
- Spray polyurethane foam (SPF roofing)
- Ethylene Propylene Diene Terpolymer (EPDM)
When discussing your options with the roofing contractor, the three essential aspects that you need to consider concerning your low sloping roof include:
- Reinforcement against wear and tear
- Weatherproofing against the elements
- Surfacing to protect the inner layers against outdoor elements and ultraviolet rays from the sun
Metal roofs are among the most preferred choices of roofing material for commercial buildings due to their excellent record of fire resistance, durability, strength, sustainability, and energy efficiency. These types of roofs are made by mechanically fastening corrugated metal or R-panels on existing structures.
The most popular metals that you can use for metal roofing include tin, lead, stone-coated steel, aluminum, copper, stainless steel, metal tile sheets, silicon-coated steel, aggregates of Zinc and aluminum, and corrugated galvanized steel. Metal roofs come in a range of color coatings for waterproofing, resistance against rust, and reflecting off the sun’s rays.
Built Up Roofing
Generally known as “tar and gravel” roofs, built-up roofs are made of several plies of mats, fabrics, and felts fastened together with either coal tar pitch, asphalt, or bitumen. They are typically made of alternating layers of bitumen and plies, as the membrane on which a final layer of either weather resistant coating, aggregate mixtures, mineral cap sheet, hot asphalt, or gravel is applied.
Built-up roofs are highly resistant to weathering and punctures not only reducing the need for roof repair, but also making them the ideal choice if you have a wide range of waterproofing applications.
Modified Bitumen Roofing
Modified bitumen roofs consist of reinforced roof fabrics that have bitumen in between the plies. Similar to built-up roof membranes, they are installed as two-ply systems laminated on the roofing surface. A blend of modern and traditional roofing technologies, they are highly resistant to tears, punctures, and foot traffic due to the use of SBS (Styrene Butadiene Styrene) and the APP (Atactic Polypropylene polymer) polymers.
SBS enhances elongation and resistance to brittleness at low temperatures while APP enhances tensile strength for resistance to foot traffic. The blend of these two technologies is driving the commercial re-roofing of many buildings that are taking advantage of this new technology.
Spray polyurethane foam (SPF roofing)
This is a foam-based type of roofing achieved by the mixing and application of a two-part liquid (close celled spray of polyol isocyanate polyutherane foam) that is applied to the base of the roofing surface. The thickness may vary depending on your desired drainage slope or insulation value. The second part of the liquid formation that protects against fire, the sun, and the weather may be either:
- Butyl Rubber
- Modified Polyutherane Elastomer
- Aliphatic Polyutherane Elastomer
- Aromatic Polyutherane Elastomer
Ethylene Propylene Diene Terpolymer (EPDM)
Unlike BUR, EPDM consists of a single ply of rubber roof membrane designed to be highly resistant to abrasion, weathering, ultraviolet rays, wind, hail, and ozone. These capabilities make it one of the most sustainable and environmentally friendly roofing materials. Being single ply also makes commercial roofing repair of EPDM easy, convenient, and affordable.
Nonetheless you need to take the following into account while using EPDM:
- Best effectiveness is achieved by using ballasted systems that can be easily and quickly installed
- For a lightweight solution for buildings of all sizes, mechanically attached systems are best
- If mechanical applications are unfeasible or undesirable, use adhesives to laminate the roof membrane to the roofing substrate
San Francisco Commercial Roofing Leaders
At Ben’s Roofing, we have years of experience working with customers to find the best fit for their building working within their budget. To explore what types of materials and methods make the most sense for your commercial structure, call us today at (510) 690-8570 so we can serve your roofing needs.