Flat roofs are common on commercial buildings, but they offer challenges you don't find with roofs that have slopes. Since the roofs are flat, rain might puddle up on the roof and cause a roof leak. That's why this type of commercial roofing has to be watertight to keep out the rain. Here's a look at how different types of commercial roofing are made watertight to protect your building. 

Plastic Membrane Roofing

Plastic membranes are popular for commercial roofs, and they have a unique way of being installed to keep water out. The roofing contractor uses heat to bond the seams of the membrane together. The heat fuses two membranes to each other to create a tight seal that keeps rain out. The risk of gaps forming along the membrane is low since there is no worry over adhesives deteriorating in the sun.

Rubber Membrane Roofing

Rubber roofing is installed in sheets that are fused together too, but these use seam tape and adhesive. The bond created is tight and usually lasts a long time. As long as the bond holds, the roofing is watertight. When the roofer makes scheduled inspections, they check the seams of membrane roofing closely. If a seam starts to open up, it is sealed by applying more tape and adhesive as a form of roof maintenance.

Built-Up Roofing

Built-up roofing is another popular choice for flat roofs. It is installed by alternating layers of felt membranes and roofing tar. Because there are multiple layers on the roof, the roofing is made watertight. The tar binds the membranes and layers together to keep the rain out.

Spray Foam Roofing

Spray foam is unique in that it has no seams to worry about. The foam flows together to create a single blanket of roofing material that even wraps around vent pipes to create flashing with no seams. This type of roofing is watertight and it can also be applied with different levels of thickness to create a slope that ensures good drainage of rain.

While all of these roofing types are watertight when installed, they can all develop leaks due to punctures. Hail strikes and foot traffic can cause puncture holes and rips that allow rain to seep under the roofing material. For that reason, it's important to have your flat roof inspected regularly to make sure it doesn't have any damage that could lead to a roof leak.

Flat roofs may have the potential to leak more than sloped roofs, but if you maintain the roofing properly, your building will have the best protection possible.

Contact a local roofing company, such as Diamond Roofers LLP, to learn more.