Flat Roofing For Commercial Properties
Flat roofing differs from the traditional room as you might guess. While a traditional roof has a pitch or slope to it, the flat roof is level – almost. But because it is a must for a flat roof drain to be possible, it must have a very slight incline of about 10°, so slight the naked eye won’t see the slope.
Flat roofing style isn’t anything new, they were used in ancient times in arid climates like Arabia, Egypt, Persia, or like countries, and used as a second living space. They may have another purpose in other countries, and they are made from different materials based on the location.
For instance, in an area that doesn’t have much rain or and the temperatures never drop to freezing, flat roofing will be made from concrete or masonry. In parts of the country where the rain is heavy and roofs may leak and the temperatures do drop to freezing, the flat style roof wouldn’t withstand that weather.
In this article, we are going to discuss flat roofing and flat roof types in some depth, answer questions that are commonly asked and the next time you plan construction of a new building, you’ll have more knowledge to know what is better for you, a flat roof or a sloped roof.
What is the best material for a flat roof?
There are three flat roofing materials, commonly back with a 10 to 20-year warranty, sometimes, depending on the area and climate, they may be warrantied for 25 years.
The Built-Up Roof (BUR)
This is the more traditional material for flat roofing, the hot-tar-and-gravel style, also known as BUR. Three or more stacks of waterproof material are used to build these roofs, alternating layers between hot tar and smooth river stone. At one time, tar paper was used instead, and as materials improved, fiberglass membrane became more popular.
The gravel acts as a fire retardant and if there is a second floor, it makes the view more attractive from decks and windows overlooking it. Of the three materials that we’ll discuss here today, this flat roofing material is the least expensive.
The first downside to this type of flat roofing material is the smell while it is being installed. And if there is a leak, it can be challenging to find. Gutters and the downspouts are clogged easily by the gravel when rain runs off.
This flat roofing material consists of a single-ply rolled roof comparable to ice-and-water shield, but it is impregnated with a surface of mineral-based wear. When this type of material is being installed, a torch-down system is used to heat the adhesive as it is unrolled. There is a peel-and-stick type available today that is easier to install and a safer process.
The Modified Bitumen
Unlike the torch-down system that required installed by a professional, the peel-and-stick flat roofing material can be done by the building owner, saving you money. This material is a light-colored mineral that reflects heat and will cut back on your energy bills. Pricing of this material is middle of the road.
A downside to this type of roofing material is the torch-down application system creates a fire hazard, and as such, it is recommended to be applied to buildings that are not occupied. This material is not as resistant to scuffs and tears as the net flat roofing material we’re going to discuss.
The Rubber Membrane
This flat roofing material is a true rubber material, ethylene propylene diene monomer (EPDM for short), is comparable to that of an inner tube. It is a durable material that resists sunlight damage and can be anchored mechanically using ballasted with stone, fasteners, or glue.
This flat roofing material is also building owner-friendly to install and is light-weight yet high resistants again scuffs and tears. Leaks are easily detected and easily patched.
The downside to this roofing material is it absorbs heat and can increase energy bills in a warm climate. It is the more expensive option and is vulnerable to damage like punctures.
What’s the best covering for a flat roof?
The options are many yet limited when it comes to covering flat roofing. What does this contracting statement mean? The traditional roofing material like asphalt shingles, concrete tiles, or corrugated metal is not an option. This leaves you with EPDM rubber, PVC, or TPO materials, each having pros and cons. From the most popular flat roofing materials, here is their expected lifespan:
- EPDM – Ten to Fifteen Years
- PVC – Fifteen to Thirty Years
- TPO – Seven to Twenty Years
Where asphalt, concrete, or clay roofing materials are installed with each row overlapping the next, working cohesively with the roof pitch so that rainwater and snow shed. Because the pitch with flat roofing is minimal, rainwater could work itself under those materials and eventually would rot the substrate with the possibility of leaks increased.
When choosing a material for flat roofing covering, there cannot be any seams, with the biggest threat being water. Water will find its way into and through anything unless the seams are adequately sealed with a roofing membrane. When covering a flat roof, it is important to choose a material that water cannot penetrate.
How do you protect a flat roof?
The flat roofing on your building is protecting your business and all inside it, most likely the biggest investment you’ll ever make. Therefore, you want to keep it in good condition and well-maintained. Here we offer you five tips for protecting it:
First, you must realize that your flat roof is completely flat. There is an ever-so-slight slope, usually of 10 degrees, that allows water to run off the roof. If your roof starts to have ponding and puddling, this indicates low spots and this can quickly turn into leaks.
By choosing the best material for your flat roofing, and the type of flat roof construction it was built with, you shouldn’t ever have to worry about that happening. Some of the best materials recommended industry-wide are:
- EPDM, PVC, or TPO – All are single-ply membrane
- BUR – Also known as Built-up roofing
- A Spray coating
- Ballast – The flat roofing material of crushed stone that is placed on single-ply roofing
Have Your Flat Roof Inspected – Experts of flat roofing styles recommend that it should be inspected twice a year, but no less than once a year. The earlier a leak or other problem is found, the earlier it can be fixed and avoid any expensive repairs to the roof and your business.
Keep Your Flat Roofing Surface Clean – When you have your flat roof inspected semi-annually, have it cleaned of any debris, litter, and organic materials. This step is one of the best protection you can give it because it keeps plant growth from occurring and will show any signs of blunt impact or punctures that have damaged it.
Avoid Walking On Your Flat Roof – Keeping physical contact to an absolute minimum and be sure that any vendor or worker that is on the roof has taken care not to disturb the roof which can cause a leak. This includes the use of tools when the HVAC system is repaired, or cables or wiring stretched across it. Friction is not a friend to flat roofing.
Consider The Best Coating For Your Climate – If the climate you’re in is a hot one and your building is exposed to a lot of sun, choose a light-colored flat roofing material versus a dark-colored roofing material for energy dollar savings. A spray-on coating is more reflective and better waterproof. Your choice of flat roofing material will determine the lifespan of your roof.
Can you stand on flat roof?
Using a flat roof can offer temptation to utilize the space for a balcony or terrace – after all, they do it in movies, right? But, in the real world, flat roofing is typically not constructed to withstand the weight of people walking on it. Even though it may not collapse right then and there, over time, it will become weak and then become hazardous.
Any roof is precarious, but a flat roof isn’t as precarious as a pitched one. However, walking on it can damage the felt and the membrane. If you must walk on your roof, or a have a contractor that will be walking on your flat roof, request they lay boards over the area they’ll be walking and walk across those instead of directly on the roof.
If you intend to use your flat roofing area for recreation or you’re considering planting a roof garden, you need to have a structural engineer inspection done to assure it is up to the weight. Otherwise, consider it to be off-limits for anyone other than a professional.
Do flat roofs always leak?
Too often, a building owner will steer away from a flat roofing system because of rumors about problems with leaking. And while they can’t shed water as easily as a pitched roof, if they are constructed correctly, they don’t have any more possibility of leaking. Keep in mind, that while they appear flat, they are in fact, have a slight pitch.
If a flat roof does leak, the culprit is usually poor construction, aka human error. When a building owner is budget-conscious, and the roofing contractor is trying to stay within their budget, they will often cut corners.
When you’re constructing something precarious already like a flat roofing system, cutting corners is the last thing you need to do. And even the tiniest mistake by the contractor can lead to a leak eventually. A well-constructed flat roof can last up to 30 years with the right material covering it. Voegele Co. is your source for quality flat roofing systems. Need flat roofing in Pittsburgh, PA? Call us today at (412) 227-8488!