Flat Roof Systems
- Modified Bitumen
This is an asphalt roofing system with modifiers added to give it plastic or rubber like qualities. The two most common types are Actactic Polypropylene (APP) and Styrene Butadiene Styrene (SBS). They have good performance on residential and commercial roofs and are recommended for slopes not less than 1/4” per horizontal foot.
- Built-up (Tar & Gravel)
This is the oldest and most reliable flat roof system, and consist of two types: asphalt and coal tar. This type of system contains three components, the water proofing component, reinforcing component, and surfacing component (protects other components from the elements) that give it great durability. Systems last between 15-25years depending on the number of plys.
TPO or Thermo-Plastic Olefin is another flat roof option. It comes in several colors: white, light grey, black or tan, and comes in two thickness: .045” and .060.” TPO has several pros and cons. This roofing system is economically affordable, versatile for many homes or businesses, durable (resists mold, dirt build-up, impact, UV and chemical exposure, and is flexible to home/building shifts), easy to install, energy efficient (heat reflective properties), and environmentally friendly (100% recyclable). However, the longevity of this roofing system is still in question because it is still a fairly new product (10years) and does not stand up well to extreme heat pressure (the thicker the material the more it can withstand heat).
Metal Roofing Systems
Metal roofing systems are a great way to go for commercial businesses and buildings. Although they can be a bit pricey, the benefits more than make up for that. These roofs are energy efficient, durable, sustainable, long term, low maintenance, fire and wind resistant, light weight and aesthetically pleasing.
Commercial buildings consume 1/3 of the energy and 2/3 of the electricity in the US according to the Metal Initiative. This is especially the case in large cities and/or cities with large energy demands. Think about the rolling blackouts that have occurred in cities such as New York due to energy shortages. Metal roofs can save up to 40% in energy usage each year, and if it is a pre-painted or granular coated metal roof it can reduce energy consumption up to 90%. This is because of the reflective quality of the roof added to the re-emissive quality. Re-emissive means that it not only reflects the sunlight but also discharges the heat into the air instead of absorbing it into the building/home.
These roofing systems are also environmental friendly or “green” roofs. They add less waste to landfills because they can be made from recycled materials, can be recycled and can be reused.
Their durability comes from the fact that they are resistant to cracking, shrinking and eroding. They can also withstand extreme weather such as snow, hail, fire and wind. Most come with a warranty of up to 50 years and some insurance companies give discounts when metal roofs are used. The slope design also adds to the durability because it allows for run-off and self cleaning. This is important in their energy saving aspect as well because they dirtier they get, the less they will reflect and re-emit. This decreases the energy savings the roof provides.
Metal roofs can be made of many materials such as corrugated galvanized steal, stainless steal, aluminum, copper, and a blended steal. Two types of coating are available-ceramic and solar reflective. They can add to the aesthetics of the building by resembling wood shake, slate, shingles or clay tiles, come in multiple colors and textures, and can be used for steep or low slope roofs.