All roofs have the same primary function: to protect the property from the elements. However, beyond this similarity, commercial and residential roofs are extremely different in many ways. These differences are significant to note when it comes to commercial roof construction. Otherwise, the building may not have the necessary protection, leaving it vulnerable to severe and costly damage.
This guide will cover new commercial roof construction with everything you need to know to ensure a proper roof design and installation.
What is Commercial Roofing? How Does it Differ from Residential Roofing?
Commercial roofing refers to roofing systems installed on any non-residential buildings. These include businesses, warehouses, and other similar, large commercial structures.
As said before, the primary similarity between commercial and residential roofing is the protection they provide. While they can have similar options, commercial roofing is more limited in its options. It is in the possible materials where they differ the most. Commercial roofing is typically more industrial, heavy-duty materials like TPO, PVC, modified bitumen, and more.
Ensuring a well-constructed and installed commercial roofing is vital not just for the protection of the building but to ensure day-to-day operation can go undisrupted.
Factors That Determine What Commercial Roof Design Is Best
Like residential roofing, a commercial roof is an investment, and the various roofing materials available for commercial roof construction offer different advantages and disadvantages. They also have different levels of durability, life expectancy, and cost. So, what factors help determine the best commercial roof for a building?
Desired Lifespan
All roofs need to be replaced at some point. The question you need to ask is, how soon do you want to replace yours? Commercial roofing is an investment, and longevity is something many desire. Therefore, you want to pay attention to the lifespan of the materials you are considering and the length of the warranty.
Durability
Durability is another critical factor to consider in commercial building roof construction. Consider the climate of your geographical location, the commercial roof should be able to withstand all of it without becoming damaged. It also needs to be able to withstand heavy foot traffic if there is rooftop equipment that will require serving. All of this will help point to the suitable material and thickness.
Energy Efficiency
Energy efficiency is another consideration that can be especially important for commercial roofing construction in hotter climates. Roofing systems with higher R-values will absorb less heat, meaning the building will not get as hot, lessening the need to put the building’s air conditioning on high levels, which will cut down on energy costs.
Commercial Roof Slope
Slope is an essential part of commercial building roof construction. Commercial roofs can be either low-sloped (or flat) or steep-sloped.
Low-Slope Roofing: Low and flat-sloped roofing systems are the most common commercial roofing you see and are typically found on warehouse buildings, big box stores, and shopping centers. This roof style allows for equipment to be installed on top, like HVAC units and other mechanical equipment that building owners would want to remain out of sight. With this roof style, material options include EPDM, PVC, and TPO.
Steep Slope Roofing: Steep-sloped roofs are more common on residential properties than commercial properties, but that doesn’t mean you can’t find commercial buildings with a steep slope. You can find this style of roofing in office buildings and educational institutions. They are also common on historic structures.
Steep-sloped roofs are better suited to traditional roofing materials, like metal roofing, shingles, slate, and tile. Steep roofs are ideal for places with heavy snow or rainfall, as the steep sides will allow the elements and debris to roll off rather than accumulate and potentially damage the roof system.
Commercial Roofing Materials
The slope of your new commercial roof construction is only the first step. Then, you must consider which system is best for your building and needs. Some of the most common commercial roofing systems include:
Single-Ply
Single-ply roofing is an umbrella term that refers to a group of commercial roofing systems that include TPO, PVC, and EPDM. All of these systems offer great flexibility and are incredibly robust. Many building owners prefer them due to their resistance against weathering, including peeling and cracking.
Their defining characteristic is that they are designed, as their name implies, for single-layer installation, which can vary in thickness. The higher the number, the thicker the membrane will be, and the longer the warranty will be.
Thermoplastic Polyolefin (TPO)
TPO is a single-ply roofing membrane that is common in North America. It involved reinforced sheets with heat-welded seams that are highly reflective. TPO membranes are composed of a combination of polypropylene and ethylene-propylene rubber that has been polymerized into a single product.
It falls into the thermoplastic membrane category and is offered in various colors, with the most popular options being white, gray, and tan. It also has the benefit of offering several installation methods.
Polyvinyl Chloride (PVC)
PVC roofing systems are a single-ply thermoplastic membrane comprising two layers, separated by a polyester reinforcement scrim. The top layer contains various additives to help make the system UV resistant, and the bottom layer is darker and contains plasticizers that help with flexibility. It is an option that offers longevity and durability for new commercial roofing construction. It is also fire resistant, and adjoining sheets can be welded together to form a watertight seal.
This ability to weld adjoining pieces can create the appearance of a standing seam roof, which could make for a more aesthetic appearance at a lower cost. PVC membranes also have the added benefit of being recyclable.
Ethylene Propylene Diene Monomer (EPDM)
EPDM is a thermoset membrane and a chemical compound known for its toughness and elasticity and is resistant to the sun’s rays. Specifically, it is a synthetic rubber composed of natural gas and oil. It is one of the most popular materials currently used because it is a resilient material that is also low-cost.
Modified Bitumen
Another roofing arterial for commercial roofing construction includes modified bitumen roofing systems. These systems combine asphalt and chemical polymer, which are known for their flexibility and temperature resistance. You can apply it in multiple layers and several different ways, including self-adhesive sheets, hot-mop asphalt, torch application, and even cold-applied adhesives.
This makes it an excellent option for installation in any season. The membrane seams are melted together, forming a secure, watertight bond. Further, modified bitumen is wind, fire, and hail resistant, making it ideal for storm-prone areas.
Built-Up Roofing (BUR)
BUR systems are some of the oldest systems for commercial building roof construction. They consist of three to five layers of fiberglass rolls and hot tar for the best protection, especially when installed in more extreme climates that can go from high to low.
The top layer is most important, as the roof is typically flooded with 450º to 500º tar, sometimes with rocks mixed in. It makes for a more durable roof that can withstand heavy foot traffic, and this top layer will help you determine if the roof can be repaired and maintained successfully. It is a more expensive option listed so far.
Metal Roofing
Metal roofs are known for their aesthetics, long lifespan, and durability. They are also one of the more versatile commercial roof construction types, compatible with other low-sloped and steep roofing systems. Two of the most common metal roofs used for commercial buildings include standing seam and screw-down systems in either aluminum, steel, or Galvalume, which are the most cost-effective options and offer a variety of aesthetics and price ranges.
Liquid Applied Systems
Liquid-applied membranes are systems constructed in place using resin and a reinforcing polyester. It can get into hard-to-reach places the other systems cannot, giving it superior waterproofing abilities. It can be sprayed or rolled on and is typically done in two coats. This application method doesn’t create strong or harmful odors so that work can continue during installation.
Green Roofs
Green roofs are not an ideal roofing option for all commercial roof construction types. They are best on flat roofs and consist of a waterproof membrane covered in growing medium and a layer of vegetation. When available, they are an excellent option as they create usable space, help reduce energy costs, and can absorb stormwater, lessening the need for costly, expansive drainage systems.
Photovoltaic (PV) Solar Panels
Everyone knows what solar panels are. PV panels can generate significant long-term savings, especially when installed in very sunny areas, by lessening your reliance on electricity.
Steep Sloped Roofing Options
Steep-sloped roofing materials are suitable for roofs with slopes of 3:12 or higher. Again, while this slope is typically seen on residential homes, commercial buildings opt for this type of commercial building roof construction, typically for the aesthetics of the design. Besides metal roofing, which is mentioned above, options include:
Asphalt Shingles
The most common type of asphalt shingles on commercial roofs are design shingles, which provide better wind protection and curb appeal. Designer asphalt shingles can last 25 to 35 years with proper maintenance, but that is much less time than other materials, and certain climate conditions can shorten their life.
Slate Roof
Slate roofing is known for its durability and extremely long life expectancy, lasting up to 100 years or more. They are low maintenance, fireproof, and wind resistant. However, they are extremely heavy, require additional structural support, are very expensive, and have a labor-intensive installation process. Tiles cost about $10 to $30 per square foot.
Clay Tiles
Clay is another aesthetically pleasing option that can give a commercial building a Latin or Mediterranean feel. Like slate, they offer extreme longevity, are resistant to fire and rot, and do very well in hot climates. Also, like slate, they are heavy enough to need additional structural support and are very expensive. They can also be brittle, especially individually, and can break during installation. They can cost around $5 to $14 per square foot.
Wood Shakes
Wood shakes and shingles can provide a rustic look that is eco-friendly and insulating. However, they aren’t fire resistant on their own, and even with fire-resistant treatments, they are banned in some areas. They are also high maintenance and susceptible to moisture and insect damage.
Synthetic Tiles
Synthetic tiles are another option that works for low and steep-sloped commercial roof construction. They are often made using recycled plastics or other sustainable materials. They mimic the styles above, offering realistic alternatives to heavy materials like clay and slate tiles and maintenance-heavy options like cedar shakes. Synthetic tiles are more durable, with fire and impact resistance.
They are also resistant to rats and insects, are lightweight, energy-efficient, and easy to install. Choosing quality brands is essential to get a reliable, long-lasting, and realistic product.
Choosing the Best Roof for Your Commercial Building
Different commercial buildings have different needs. Before you choose one of these materials, it is essential to consider all possible factors: the slope of the roof, the amount of foot traffic, the climate, longevity, etc. These will help you make the best choice for your new commercial roofing construction, ensuring you have the perfect roof.
Contact Brava today to learn more about our synthetic roofing materials.
