Why Do Commercial Buildings Have Flat Roofs?

Most commercial buildings have flat roofs in the U.S. But is there any reason behind it or is it just a coincidence?

At McClellands Contracting and Roofing, LLC, we are your local roofing professionals serving Pittsburgh and the nearby regions in Pennsylvania.

In today's article, we will go over why flat roofing systems are commonly used on commercial buildings. If you are looking for high-quality roof installations in Pennsylvania, feel free to call us today at (412) 353-5660.

Reasons Why a Flat Roofing System is Popular for Commercial Buildings

Here are just some of the reasons why flat roofs are a common choice for commercial buildings.

#1 Cost-Effective Installation and Materials

One of the biggest reasons why commercial buildings have flat roofs is simply because they are more cost-effective. Flat roofs require fewer materials to cover the same square footage compared to pitched roofs. 

The installation process is also much faster and simpler, which means lower labor costs for building owners. For large commercial spaces, this cost difference can be substantial, making flat roofs an affordable choice that makes sense for most business owners.

#2 Increases Interior Space 

Commercial flat roof construction allows businesses to make the most of their interior space. Unlike pitched roofs that create awkward angles and unusable areas, flat roofs provide a straightforward ceiling structure that increases the usable square footage inside. 

This is especially important for commercial buildings where every inch of space translates to potential revenue. Whether it's retail space, office areas, or manufacturing floors, flat roofs help businesses utilize their interior space efficiently.

#3 Perfect for Equipment Placement

If you've ever looked at commercial buildings from above, you've probably noticed that many flat roofs are home to HVAC systems and other equipment. This is one of the most practical reasons why flat roofs are common on larger commercial buildings. 

The flat surface provides a suitable place to install air conditioning units, ventilation systems, and other necessary equipment without taking up interior or ground-level space. Plus, placing this equipment on the roof keeps it secure from vandalism and reduces noise inside the building.

#4 Better Energy-Efficient Options

Modern commercial flat roofs are generally very energy efficient. Many flat roofing materials are available in light colors or with reflective coatings that lower the amount of heat absorbed into the building. This "cool roof" effect can lower cooling costs in warmer months, making flat-roof commercial buildings more energy-efficient. 

Some buildings even use their flat roofs for solar panel installation, further enhancing energy savings and sustainability.

#5 Simplified Maintenance and Access

When it comes to maintenance, flat roofs on commercial buildings are much easier to access and work on. Maintenance crews can walk safely on the surface without special equipment or extensive safety gear that would be needed on steep slopes. 

This ease of access makes regular inspections, repairs, and maintenance much simpler and less expensive over time. For building owners and property managers, this translates to lower long-term maintenance costs for commercial flat roofs.

#6 Additional Usable Space

A flat roof commercial building gains extra usable space that simply isn't possible with pitched designs. The roof itself can become a functional space for various purposes. 

Some businesses use their flat roofs for employee break areas, rooftop gardens, additional storage, or even as event spaces. This extra usable area can be a significant advantage, especially in urban areas where ground space can be limited.

#7 Advanced Drainage Systems

While most people think water drainage would be a problem for flat roofs, modern commercial flat roof construction includes sophisticated drainage systems specifically designed to handle water efficiently. 

These systems use slight slopes (generally 1/4 inch per foot), interior drains, scuppers, and sometimes siphonic systems that move water much faster than traditional gravity drainage. These advanced systems ensure water doesn't pool on the roof, protecting the building from potential leaks and water damage.

#8 Long-Term Durability

Materials like TPO, EPDM rubber, modified bitumen, and built-up roofs can provide decades of service when properly installed and maintained. 

Some commercial flat roofing systems can last up to 30 to 50 years, making them a durable and reliable choice for business owners who want long-term protection without frequent replacement costs.

#9 Fits Modern Construction Methods

The flat roof structure works particularly well with concrete and steel building techniques commonly used in commercial construction today. These materials expand and contract at different rates from wood, making flat roof designs more compatible with contemporary building materials than traditional pitched roofs would be.

Can You Install a Pitched Roof on a Commercial Building?

Yes, it's technically possible, but it is very uncommon because pitched roofs are complex to install on large commercial buildings. 

The larger the building's footprint, the more challenging and expensive it becomes to construct a pitched roof. The framing requirements alone would add significant costs and construction time to the project.

Additionally, pitched roofs make it difficult to place HVAC systems and other equipment that are typically installed on commercial roofs. 

Most businesses find that the practical benefits of flat roofs simply outweigh any aesthetic advantages that pitched roofs might offer for their commercial buildings.

Get Professional Commercial Roof Services in Pennsylvania

McClellands Contracting and Roofing, LLC, is your trusted local roofing company based in Pittsburgh, Pennsylvania. We are committed to providing high-quality home improvement and roofing services in Pennsylvania. 

Our team can help you choose the best flat roofing solution for your specific needs. Whether you need a new flat roof installation, repairs to your existing commercial roof, or just want an expert opinion on your current roof's condition, our professionals have the skills and experience to deliver exceptional results. 

We work with all types of commercial flat roofing materials and can recommend the best option based on your building's requirements, local climate conditions, and your budget.

To schedule a free roof inspection today or for a no-obligation discussion with our professionals, contact us at (412) 353-5660.