Exploring the Different Types of Flat Roofing Systems  

Flat roofing systems are a popular choice for commercial and residential buildings due to their modern look, cost-effectiveness, and the ability to maximize usable space. Whether you're considering a new roof for a commercial property or replacing an existing one, understanding the various types of flat roofing systems available is essential for making an informed decision. 

At The Roofers, we specialize in providing expert flat roofing services for the Greater Toronto Area (GTA). In this blog, we will explain the most common types of flat roofing systems, their benefits, and the best use cases for each.

1. Built-Up Roofing (BUR)

Built-Up Roofing (BUR), also known as tar and gravel roofing, is one of the oldest and most reliable flat roofing systems available. It is made up of multiple layers of asphalt or bitumen, reinforced with a variety of materials such as fiberglass or polyester, and topped with gravel or a reflective coating. 

Advantages of BUR: 

• Durability: BUR systems are known for their long lifespan, often lasting 20-30 years with proper maintenance. 

• Weather Resistance: This roofing system is resistant to extreme weather conditions, including heavy rain, snow, and UV rays. 

• Cost-Effective: BUR is one of the more affordable options for flat roofs, especially for large commercial buildings. 

Ideal Use: 

BUR is suitable for both commercial and residential flat roofs and is particularly effective in regions with harsh weather, where a durable and long-lasting roofing solution is needed.

2. Modified Bitumen Roofing

Modified bitumen roofing is a modern evolution of BUR, offering improved performance and flexibility. It consists of asphalt that has been modified with polymers (usually APP or SBS) to enhance its resistance to UV rays, water, and temperature fluctuations. Modified bitumen systems are typically installed in two layers, with a base sheet and a cap sheet, which are either heat-welded, self-adhered, or cold-applied. 

Advantages of Modified Bitumen: 

• Flexibility: The polymer modification allows for better flexibility and resistance to cracking, even in extreme temperatures. 

• Ease of Installation: Modified bitumen is easier to install than BUR because it can be applied with various methods, including torching or self-adhesion. 

• Lower Maintenance: This roofing system requires minimal maintenance and is resistant to punctures and tears. 

Ideal Use: 

Modified bitumen roofing is perfect for both residential and commercial properties, especially those in climates with significant temperature swings. It is a popular choice for flat roofs that require flexibility and durability.

3. EPDM (Ethylene Propylene Diene Monomer)

EPDM is a synthetic rubber roofing material that is widely used for flat roofs. This single-ply roofing membrane is known for its resilience and excellent weather resistance. EPDM comes in large rolls that are typically installed using adhesive, mechanical fasteners, or ballast. 

Advantages of EPDM: 

• Longevity: EPDM roofs can last up to 40 years when properly installed and maintained. 

• Energy Efficiency: EPDM membranes reflect UV rays, which can reduce the amount of heat absorbed by the roof, improving energy efficiency. 

• Low Maintenance: Once installed, EPDM requires very little maintenance and is highly resistant to tears, punctures, and UV degradation. 

Ideal Use: 

EPDM is an ideal choice for commercial and industrial buildings with large, flat roof areas. It is especially effective in warmer climates or urban areas where energy efficiency is a priority.

4. TPO (Thermoplastic Olefin)

TPO is another single-ply flat roofing membrane made from a blend of polypropylene and ethylene-propylene. Known for its energy efficiency and durability, TPO is often used for both commercial and residential flat roofs. The membrane is available in a range of colors, with white being the most popular due to its reflective properties. 

Advantages of TPO: 

• Energy Efficiency: TPO reflects UV rays, which helps to reduce cooling costs by keeping the building cooler. 

• Seam Strength: TPO membranes are welded together using heat, creating strong seams that resist leaks. 

• Environmentally Friendly: TPO is one of the most eco-friendly flat roofing options due to its recyclable materials. 

Ideal Use: 

TPO is perfect for both residential and commercial flat roofs that require energy efficiency, particularly in areas with hot climates. Its excellent seam strength and UV resistance also make it a great choice for buildings that need superior protection from water infiltration.

5. PVC (Polyvinyl Chloride) Roofing

PVC roofing is another type of single-ply flat roofing membrane. Known for its durability, chemical resistance, and long lifespan, PVC roofing is often used for commercial and industrial buildings. The membrane is heat-welded at the seams to form a strong, watertight bond. 

Advantages of PVC: 

• Durability: PVC roofing is resistant to punctures, tears, and water, making it an excellent choice for flat roofs in areas with heavy rainfall or foot traffic. 

• Fire-Resistant: PVC is naturally fire-resistant, providing an additional layer of safety for commercial buildings. 

• Low Maintenance: This roofing material is easy to clean and maintain, reducing long-term upkeep costs. 

Ideal Use: 

PVC roofing is ideal for commercial and industrial properties, especially those that require a high level of durability and resistance to chemicals, oils, and harsh weather.

6. Green Roofs (Living Roofs)

A green roof is a flat roof covered with vegetation, either partially or fully. Green roofs are a sustainable, eco-friendly option that provides insulation, absorbs rainwater, and helps to reduce the urban heat island effect. While not a traditional "roofing system," green roofs are becoming increasingly popular as a way to improve environmental impact. 

Advantages of Green Roofs: 

• Environmental Benefits: Green roofs help reduce air pollution, improve air quality, and promote biodiversity. 

• Energy Efficiency: The natural insulation provided by green roofs can significantly reduce heating and cooling costs. 

• Stormwater Management: Green roofs absorb rainwater, reducing the strain on municipal stormwater systems. 

Ideal Use: 

Green roofs are best suited for commercial buildings in urban areas where sustainability and environmental responsibility are priorities. They are particularly beneficial for those looking to improve energy efficiency and reduce their carbon footprint. 

Choosing the Right Flat Roofing System 

Each flat roofing system has its unique set of benefits, and choosing the right one depends on factors like climate, building type, and budget. Whether you're looking for the durability of BUR, the energy efficiency of TPO, or the eco-friendliness of a green roof, The Roofers can help you select and install the best roofing system for your needs. 

At The Roofers, we specialize in providing expert advice, high-quality installation, and ongoing maintenance for all types of flat roofing systems in the Greater Toronto Area (GTA). If you're ready to upgrade or replace your flat roof, contact us today for a consultation!