If you are thinking of installing a flat roof, here’s what you need to know.
Whether your existing flat roof requires a total makeover or you are putting a flat roof on a new residential or commercial property, there are many flat roof materials available. Flat roofs are an attractive option for any property because they last longer than other materials, have minimal maintenance requirements, and are energy efficient. Here is a list of the Top 5 Flat Roof materials used today:
Ethylene Propylene Diene Monomer, also known as rubber roofing
EPDM consists of a large single-layered roll of durable synthetic rubber roofing membrane. It is installed by applying an acrylic bonding agent. It is the cheapest of the flat roof options and one of the easiest flat roofing solutions to install. Because it is easier to install, property owners save time and money during installation.
But there are several disadvantages of EPDM. First, it is black in color and its rubber surface tends to heat up in the sun. This can have a negative impact on the heating & cooling bill of the property owner. Second, because EPDM is made of black rubber, it tends to expand and contract as it heats from the summer sun and cools during the winter. This can lead to seams coming apart over the years. Thus, EPDM flat roof systems need regular inspection and maintenance to stay watertight.
First introduced in the 1990s, TPO is a flat roofing solution that has continued to grow in popularity. While more expensive than EPDM, TPO is easier to install. TPO is made of a heat-reflective single-ply polypropylene membrane. This type of flat roofing material is very lightweight and is laminated. The lamination keeps flat roof problems like algae or fungus from being able to grow on it. TPO is made of a white material. Many property owners like the white color as it reflects the Sun’s heat and helps in lowering the heating & cooling bill. TPO is a specialized flat roofing material, so a flat roofing contractor is recommended for both installation and maintenance of it. TPO roofing lasts an average of 15 to 20 years.
PVC has been around longer than TPO. Like TPO, PVC comes in lighter colors and is therefore highly reflective of the Sun’s heat. It is debated that TPO has a slightly better tear and break resistance and superior weathering than PVC. Having said that, PVC has characteristics that certain customers prefer and/or need. PVC has better chemical resistance than TPO. Oils and greases do not get absorbed into it which would lead to weakening the membrane. With PVC, the welded seams can be rewelded over the roof’s lifetime, and are stronger than the material itself. These characteristics make PVC the preferred flat roof membrane for restaurants and other commercial buildings that have grease traps on the roof. Finally, different from other roofing membranes, PVC trim from manufacturing is entirely recyclable. Post-consumer membranes can be returned and made into new membranes.
Also Known As BUR
Built-Up Roofing has a long track record and has been used in the United States for over 100-years. Built-Up Roofing is often referred to as tar and gravel roofing. Unlike the single-ply roofing options that are so popular today, this type of roofing is created by alternating layers of bitumen and fabrics together to form a “membrane.” That membrane is then finished with an aggregate layer or coating. Typically, underneath a BUR Roof is a rigid insulation layer. After that, there are layers of felts, fabrics, or mats that are saturated with bitumen. The most common being asphalt (which works as a better fire retardant than the others). Other types include cold-applied adhesive or coal tar.
When the roofers are spreading a gooey black substance on their roofs with mops and mechanical spreaders, you might have been watching them create built-up roofs. Built-up roof finishes often resemble rocky beaches because they contain gravel, slag, and small rocks mixed in with the asphalt. Built-up roofing systems have a variety of options, including mats that reinforce the ply sheets and types of bitumens used.
Modified Bitumen Roofing
Also Known as Torch Down Roofing
One of the most popular and fastest-growing flat roof systems in residential and commercial applications is modified bitumen flat roof systems (MBS). To seal the roof, a modified bitumen system uses a special combination of coated basemat layers instead of applying a hot liquid adhesive to the uncoated basemat. Modified bitumen flat roof systems have a reduced installation time when compared to a BUR flat roof systems. Another great advantage of a modified bitumen flat roof system is that you can install it on top of an older modified bitumen flat roof without taking off the old roof. Using this method, the flat roof actually becomes stronger and resists punctures due to the increased layers’ thickness. Not having to pay for the tear-off of the old modified bitumen flat roof systems is a huge cost-savings benefit.
There are two basic types of modified bitumen flat roof systems: 1) Torch-down and 2) Self-adhering:
Flat Roof Torch-Down Systems are installed with the help of specially designed substrates using a special combination of layers to torch-seal the bituminous product layers.
Self-Adhering Flat Roof Systems (SAS) are similar to conventional modified bitumen flat roof systems. The Self-adhering Flat Roof system uses a coated bitumen basemat to provide a waterproof seal on low-sloping and flat roofs. When a torch cannot be used, this product is ideal. Garage roofs or extending porches that intersect with wood or vinyl siding are common places where you will see a Self-Adhering Flat Roof system.
Trust GoTech Roofing in Washington DC and Northern Virginia
For over a decade, the team at GoTech Roofing has provided high-quality roofing services in Washington DC with flat roof repair and flat roof replacement services and in Arlington VA with flat roof repair and flat roof replacement services. Whether you need repairs or a roof replacement, you can count on our workmanship to take care of your roofing needs. Flat Roofs – Everything You Need to Know