
Taking Care of a Flat Roof
It isn’t exactly unknown that the winters in Pennsylvania and the surrounding area take a toll on everything. And after a few years of those harsh winters, flat roofing can start looking old and worn, even if a roof isn’t that old. So, does this mean your need to invest in a new roof?
Not necessarily! A cheaper option is to have a professional roof coating applied. What is the best coating for a flat roof? Experienced commercial roofing contractors will recommend a silicone coating for flat roofing update. It has become a popular material above the other roof coating materials that have been used for the past decade. But why?
The benefits of using silicone for flat roofing coating may seem very few, but they are important:
- Aesthetics
- Leak protection
- Improved sustainability
- Extends flat roofing lifespan by 10 to 15 years
For the aesthetics, it won’t have the chalky, shedding that other coatings applied to flat roofing gain after some time. It can indefinitely withstand ponding water because it isn’t water based and doesn’t absorb any moisture. And it doesn’t need to be reinforced with roof fabric, which is a money save on install time and labor. Another money saver is that it takes less silicone for roof coating than other coating materials, almost half as much!
What material is used for a flat roof?
What we refer to as flat roofing is actually Low Slope Roofing. The structures with this type of roofing are used for big box stores, shopping centers, and warehouses. The flat roofing on these structures can be made of four different most commonly used materials:
- EPDM: Ethylene propylene diene monomer is a chemical compound that has elasticity and toughness, which has made it ideal for commercial structures for many decades. It is resistant to ultraviolet light and the damaging rays of the sun. It is inexpensive for commercial roofing but is durable and long-lasting.
- PVC: PVC roofing consists of two layers and has a reinforcement of polyester scrim in between the layers. The top layer is UV resistant, and the bottom ply provides the flexibility that roofing contractors prefer. A durable membrane that is fire resistant. The seams are welded to make it watertight and when completed, it has an appealing visual.
- TPO: This material includes reinforced roof sheets that are heat-welded. A highly reflective membrane made of polypropylene and ethylene-propylene rubber, available in several colors and can be attached with adherence ballasted.
- Modified Bitumen Roofing: A combination of asphalt and a chemical polymer makes this a flexible flat roofing material that is temperature resistant. It is applied in multiple layers using either self-adhesive sheets, hot-mopped asphalt, or torch applied, as well as cold-applied adhesive. Because of how it is installed, it can be installed year-round and when the seams melt together, they are a secure bond that holds up to hail, fire, and high winds.
How long does a flat roof last?
The weather, the material, and the quality of the workmanship installation will all factor into the lifespan of commercial flat roofing. A typical commercial flat roofing membrane can last up to 25 years before it needs replacing. If the workmanship is low quality and the weather is brutal, it may only last 10 years. A professionally installed roof coating of silicone can extend the life by another 10 years.
What is the longest-lasting flat roof material?
A single-ply PVC flat roofing is the longest lasting. It is typically has a lifespan of 15 year minimum and up to 30 years.
What are the disadvantages of a flat roof?
It is important to choose the right roof style and material for your commercial structure. So, if you go with flat roofing, what are the downsides you can expect?
- The larger the building the more unstable flat roofing becomes. They are less costly to construct, but there are important measures that have to be taken to keep them safe.
- A limited lifespan of up to 15 years on average. However, some can last up to 25 years and professional roof coating can help with the longevity.
- Drainage is a common problem with flat roofing. When installed correctly with plenty of drains, it may never be a problem.
- Shrinkage is another common problem. Some flat roofing membranes are more prone to shrinkage than others, and with shrinkage comes leaks.
How do you waterproof a flat roof?
A silicone coating over flat roofing is one of the best waterproofing steps you can have done to your commercial structure.
Can a flat roof be metal?
Yes, and corrugated metal for flat roofing is ideal when coated with zinc. Whether you choose aluminum, copper, stainless steel, or tin, a commercial structure with metal flat roofing is durable, will have a long lifespan, and is heat resistant. Additionally, metal flat roofing will withstand high winds and is impact resistant.
Can I turn my flat roof into a green roof?
Yes, after you’ve had a structural engineering inspection performed. A green roof can help with the utility bills, lessen its footprint on the environment, and be a place for employees and visitors to relax. However, they do require a weight load and you want to make sure the structure can hold up that load without causing any problems.

At The Top Of It All
What are the parts of a flat roof called? Just because it is flat roofing doesn’t meant there isn’t much to one. Maybe not as much of the same things as a sloped roof, but the main components include:
- The Plasterboard Ceiling – The interior part visible to everyone inside the building. All other materials for flat roofing will be on top of the plasterboard.
- Decking: This is the skeleton part of flat roofing, typically made of wood beams that are attached together to form the roof.
- Insulation and Vapor Barrier: Two important parts of flat roofing is the insulation and vapor barrier. Both work to keep the roof cool and dry while it protect the decking from heat or moisture damage. The insulation absorbs and retains sunlight, so the roof isn’t damaged by heat easily.
- Waterproof Layer and Covering: Every roof, flat roofing or sloped roofing needs waterproofing fabric or sheet on top of the other parts. This keeps rain and snow away from the flat roofing should a leak develop.
By bearing all this in mind, you can take the necessary steps to keep your flat roof in shape and looking great.