What Should You Know About 2-Ply Commercial Roofing?

Posted on: 25 January 2022


Commercial roofing comes in many flavors, but most people think of flat roof membranes in a commercial context. Flat roofing minimizes construction costs, so it's a standard option on large structures utilized primarily for businesses. However, flat roofs also come with their own challenges and require specialized roofing techniques.

While the underlying structure of these roofs is often highly durable, maintaining that structure requires the installation of a waterproof protective membrane over the top. Typical systems include thermoplastic polyolefin (TPO) and EPDM. These systems are known as 1-ply roofing since they go on in a single layer, but they aren't the only option available.

2-Ply Roofing Explained

Commercial roofing can consist of numerous layers, depending on the specific needs of the structure and the budget of its owner. 2-ply roofing is an upgrade from 1-ply systems, although it's not the thickest option available. Built-up roofing (BUR) options use multiple coats of asphalt to build a durable and thick watertight layer.

2-ply roofing systems consist of a base layer mat with a modified bitumen membrane applied to the top. The primary advantage of a 2-ply system is that it provides drastically more thickness and longer life when compared to single-ply roofing membranes. Unlike these thinner membranes, a 2-ply system can resist punctures and wind damage, offering similar strength to thicker BUR roofing systems.

When to Choose 2-Ply Roofing

2-ply systems offer more strength and durability than single-ply systems, but this isn't the only reason to consider this roofing option. One common issue with single-ply systems is their relative inflexibility. These systems require a flat, clean roofing surface, and you'll usually need to remove any existing membrane before you can begin your installation.

On the other hand, modified bitumen roofing is easier to install over an existing roof and offers more flexibility for structures with unusual shapes or special needs. In some cases, it may be cheaper to go with a 2-ply system simply because the difficulty of installing a single-ply system may substantially increase labor costs.

These systems also work well for roofing that serves a functional purpose with the building. For example, if you have HVAC or other maintenance equipment mounted on your roof. Since maintenance personnel will need to access the top of the structure routinely, a 2-ply system can offer much better protection against accidental punctures or damage.

Remember that all forms of commercial roofing ultimately have their own set of pros and cons. Before deciding on the best option for your building, you should schedule an initial inspection with an experienced contractor to determine which system will work best for your structure's needs.

For more information on commercial roofing, contact a company like Drey Roofing.