Benefits of a Mechanically Fastened TPO Roof

Single-ply roofing systems are typically installed one of three ways: fastened mechanically to the roof deck, ballasted with stone or fully adhered with an adhesive. This post looks into the benefits of a mechanically fastened TPO roof. The most important fact is having a good, clean roof substrate, and keeping any loose debris clear of the membrane before installation. Mechanically fastened roofs are by far the most common, dominating around 80% of the market. They can be installed faster and at a lower cost. Builders like them because they can be easily inspected by the manufacturer, who can quickly validate the workmanship by verifying the fastener pattern and their proper installation. On top of most buildings is a metal deck, then a layer of insulation, then the roof. When installing mechanically attached roofs, the TPO membrane roll is laid down and then the screws are driven directly through the insulation boards into the metal deck below. Typically the screws are drilled in at the edge of the membrane roll then covered with the edge of the next sheet as the rolls are successively put down. A watertight seal is then created by heat-welding the membranes together with a hot-air gun. This seals any gaps and creates a single, flat, waterproof surface. There are many benefits to a mechanically fastened TPO roof, which include: Other benefits […]

4 of the Most Common Commercial Flat Roof Repairs to Expect

Commercial flat roofs are industrial structures that need careful installation and maintenance. When excellently done and if properly maintained, commercial flat roofers will tell you that a quality roofing installation will last upward of twenty five years. Unfortunately, commercial flat roofs may not attain the twenty five year lifespan because of weather and calamities. Snow overload, excessive heat, humidity build-up, and condensation are all factors that may affect commercial flat roofs. Humidity build-up, extreme heat, and snow build-up on commercial flat roofs may cause cracks, voids, or holes. Below we take a look at the most common commercial flat roof repairs: Holes are common in commercial roofing. Dropped tools, knives, and sharp objects may cause mechanical damage, leading to holes. The presence of holes in commercial roofs implies the leakage of rainwater, snowwater as well as the direct penetration of sunlight. So, patching holes caused by mechanical damage and sometimes aging is one of the most common flat roof repairs – especially for commercial roofs – whether EPDM, TPO, PVC, or asphalt. Flashing repairs are another category of repair for commercial flat roofs. Flashing details are often the most difficult part of a flat roof installation, which makes them a likely source for roof leaks. Checking to see how walls, rooftop units, roof drains, etc. are installed is a good start to finding your leak […]

Rhino Bond

kRhinoBond roof systems have been installed since the late 2000’s. They are known for having the benefits of a mechanically attached system, where the membrane is fastened to the deck, along with the benefits of a fully adhered roof system, where fewer gaps exist between where fasteners are installed. With a RhinoBond Roof system, special insulation plates are used that are coated so that a heat welded system can adhere to it. As a result, Rhino Bond can only be installed on a TPO Roof System or a PVC Roof System. The way RhinoBond works is the rigid insulation is laid out and installed the same way a mechanically fastened rigid insulation system is installed. The only difference is the type of plate used, and the number of plates used. Notice in this picture, the plates are gold, which is the color used for a TPO Roof System. Once the insulation is installed, the membrane is rolled over the insulation. After the membrane is down, the RhinoBond welding tool is placed over an insulation plate, and is induction welded to bring the plate to 500 degrees. After, a cooling clamp is placed over the insulation plate for 30 seconds, then removed. The final result is that the TPO Membrane or PVC membrane is fully welded to the plate. As with any mechanically fastened roofing system, a better wind rating comes with more […]

Fully Adhered

Fully Adhered roof systems have been installed since the mid 1960’s. They are known for being aesthetically pleasing and having the least amount of membrane fluttering, since every square foot of membrane is bonded to the insulation. Manufactures also give fully adhered roofs the highest wind ratings, whether it is a fully adhered TPO roof system, or a fully adhered EPDM roof system. However, it is important to note that factory mutual gives higher wind ratings to mechanically fastened roof systems, since it’s easier to add more fasteners to weak points in the roof system, such as the corners and perimeters. Fully adhered roofing systems rely on the rigid insulation to be fastened down thoroughly. As a result, fully adhered roof systems have fastening patterns of 12-24 fasteners per 4’ by 8’ rigid insulation board, far more than the 5-8 fasteners required for mechanically attached roof systems. The result is that fully adhered roof systems typically have more fasteners installed than mechanically attached roof systems! Once the insulation has been thoroughly fastened down, the roofing membrane is rolled out. Then, the bonding adhesive (or glue) is applied to both the rigid insulation and the membrane. After, the membrane is placed on top of the rigid insulation, then rolled in for a tight bond. Where there are angle changes, for example around walls or rooftop units, the membrane is fastened and glued down […]

Mechanically Fastened

Mechanically Attached Roof System Mechanically Attached roof systems have been installed since the late 1960’s. They are known for consistency and strength, since a fastener goes directly through the membrane and insulation on its path to attaching itself directly to the structural deck of the building. All mechanically attached roof systems have two core components, the fastener and the plate. On the insulation and separately on the membrane, a plate is laid down first, and then a fastener is driven into the structural deck. They are both laid out in accordance with a fastening pattern specified by the manufacturer. The number and location of the plates and fasteners is based on the warranty, wind speed, FM rating (if applicable), and numerous other factors. Extra fasteners are typically installed along the corners and perimeter of the roof system, where wind hits the hardest. Extra fasteners are also installed on the perimeter of rooftop units, drains, and other rooftop penetrations to prevent the membrane from lifting or sagging during angle changes. Thicker fasteners also may be required based on the wind rating of a particular building. All fasteners are then covered by membrane. The insulation fasteners, which are installed first, are covered by the top layer of the roof system, which is the membrane itself. The fasteners in the membrane are then covered by membrane from the next […]

Membrane Installation

Flat Roof Membrane is installed directly over the rigid insulation. Membrane is the weatherproofing portion of the installation, and needs to be fully installed over the rigid insulation and any roof penetrations to make the building watertight. There are many different membrane products that can be used, and many different installation techniques. Every type of membrane product used in flat roofing is unique with its own strengths and weaknesses. For more information on the most commonly used membrane products, see our pages below on: Single Ply membrane roofs, like EPDM Membrane and TPO Membrane, can be installed a few different ways. The most commonly used membrane installation methods are: Asphalt based products, like modified bitumen and built up roofs (BUR) have their own installation methods. No matter what roof membrane product you use, the installation is comprised of two aspects: Field work and detail work. The field work, for the most part, is the easy portion where the membrane is installed over open, flat areas. The detail work is the harder portion, which includes areas like HVAC units, skylights, walls, roof hatches, and other penetrations and rooftop equipment in the roof system. Over 90% of flat roof leaks come from the detail portion of the flat roof work, so it is important to have an expert crew performing any membrane installation work. After the membrane […]

PVC “Vinyl” (Polyvinyl Chloride)

PVC Roofing Systems have been installed since the 1960’s and was one of the first single ply materials used in roofing. PVC Roofs come in thicknesses from .036 mil to .090 mil, can only be reinforced. PVC is typically white, tan or gray in color. A PVC membrane installation can be mechanically attached, fully adhered, Rhinobond or ballasted. Like TPO roof systems, PVC Membrane rolls and flashing membrane are heat welded together, creating the strongest bond available in a roofing system. A PVC Roof installation is heat welded together using computerized hot air equipment that reaches temperatures of around 800 degrees in the seams. For welding the seams on open membrane rolls, an automatic “robotic” welder is used that automatically sets the correct temperature, applies the perfect pressure, and sets the best speed to perfectly weld the two membrane sheets together. For smaller areas, like rooftop units and curbs, a hand-held heat welding gun is used, along with a rubber roller. These smaller detail areas rely heavily on the craftsmanship of the roofing mechanic to achieve the correct temperature, pressure and speed required for a perfect weld. Benefits of a PVC Roof PVC Roofing systems have solid strengths. Some Benefits of a PVC Roof are: Drawbacks of a PVC Roof In the roofing industry, PVC roof systems are being overtaken by TPO, because TPO holds […]

EPDM “Rubber” (Ethylene Propylene Diene Monomer)

EPDM Roofing Systems have been installed since the early 1970’s. An EPDM roof system comes in thicknesses from. 045 mil to .090 mil, can be reinforced or non-reinforced, and is typically black in color, but can be white.. An EPDM membrane installation can be mechanically attached, fully adhered, or ballasted. Since the 1980’s, individual membrane rolls are typically bonded together using 3” or 6” seam tape, which is far superior to the liquid adhesives that were used prior. While not as strong as heat welded systems found in TPO Roof Systems and PVC Roof Systems, seam tape does an excellent job of bonding the two rolls together for extended periods of time. The way the bonding works in an EPDM Membrane Installation is the EPDM Roof membrane is cleaned off then primed. Once the primer is set, the seam tape is rolled over the primed area, and rolled into place. After, the two rolls are bonded together for the life of the EPDM roof system! For smaller areas, like rooftop units and curbs, EPDM membrane from the field sheet is custom cut and wrapped around the units. For corner areas, where the membrane must be cut perfectly to fit around the unit, flashing membrane is used due to its flexibility and versatility. The surrounding area is cleaned and primed first; the same way seam tape […]

Snow Shoveling

During winters where heavy snow continually falls on flat roofs, weight load can become an issue. By using Chaffee…

Roof Repairs

Fixing minor problems here and there, or taking on bigger projects like stripping in the seams, can stop leaks…