Understanding Flat Roofing Systems

March 30, 2023by Nick

Flat roofing systems are a popular choice for many commercial and residential buildings. They have a distinctive look and can offer several benefits including affordability, ease of maintenance, and space utilization.

This article will explore the differences in flat roofing systems to help you make an informed decision about whether it’s the right choice for you.

What Is a Flat Roof?

A flat roof is a roof that is nearly level, with a shallow pitch of no more than 10 degrees. So not completely flat, but close to it.  Flat roofs are typically constructed using a layer of insulation over a waterproof membrane. This creates a barrier that keeps moisture from entering the building’s interior.

Examples of Flat Roofs

Flat roofs are ideal for residential buildings because they make efficient use of space, allow for easy installation, and often cost less than other roofing systems. Some examples of flat roofs for residential buildings include rubber membrane roofs, Flintlastic, modified bitumen roofs, TPO roofs, built-up roofs (BUR), PVC membranes, single-ply membranes, and EPDM roofing.

What Is a Rubber Membrane Roof?

A rubber membrane roof is a type of flat roof made from a rubber material that is installed in layers. It’s lightweight and easy to install but it has some potential drawbacks such as the potential for cracking or puncturing over time.

What Is a Modified Bitumen Roof?

A modified bitumen roof is also a type of flat roof made from asphalt and rubber. It’s typically installed in layers like a rubber membrane roof, but the layers are bonded together for extra strength and durability. This makes it more resistant to weathering than a rubber membrane roof but it can still crack or puncture over time.

Considering TPO roofing?

If you are searching for a cost-effective roofing option that fits your needs, a TPO roof from St Joseph’s Roofing could function as the perfect option. TPO roofs are durable and resistant to debris build-up, bacteria, and dirt leaving your roof with a cleaner appearance and sustainable infrastructure. The flexibility of our TPO roofs makes it less susceptible to tears and other impact damage. Our goal is to deliver a solution that meets your needs without disrupting the harmony of your day-to-day life or workflow in your business.

What Is a Built-Up Roof (BUR)?

A built-up roof (BUR) is a type of flat roof made from several layers of asphalt, tar, and gravel. These layers are typically covered with a protective membrane to create a waterproof layer. BURs are known for their durability and resistance to water damage but they can be more expensive than other types of flat roofs.

What Is a PVC Membrane Roof?

PVC membrane roofing is a type of flat roof made from PVC material. It’s lightweight and easy to install, but it can be more expensive than other types of flat roofs and may require specialized maintenance.

What Is a Single-Ply Membrane Roof?

Single-ply membrane roofing is a type of flat roof made from one single layer of rubber material.  It’s another lightweight and easily installed roof but it can also be prone to cracks and punctures.

What Is an EPDM Roof?

An EPDM roof is a type of flat roof made from ethylene propylene diene monomer (EPDM) rubber material. It’s known for its high resistance to water damage and long-life span but it can be more expensive than other types of flat roofs.

What is CertainTeed Flintlastic®?

Is your flat roof looking old and worn, is the color too contrasting to your shingle color…?? If you answered yes to either question, then consider installing CertainTeed’s Flintlastic Low-Slope System.

Self-adhered roofing offers the time-tested protection of modified bitumen roof systems for a fraction of the labor with no fumes, flame, asphalt kettle or occupant disturbance. The application of self-adhered low-slope roof systems is also easier to master than traditional bituminous application methods.

As a residential homeowner you are no longer confined to the old color standards of white or black. By installing Flintlastic, you have the opportunity to remove the current “eye-sore” and select a color that closely matches your existing shingle color. Not only do you achieve a roof that is more appealing, but if your current flat roof is black, you can significantly reduce the radiant solar heat you feel during those hot, humid summer months by selecting are more energy conscious color.

When to Install a Flat Roof

Flat roofs are particularly beneficial when the building’s design involves a large surface area where a pitched roof would be difficult to install. Flat roofs are also ideal for buildings that have an emphasis on outdoor living such as rooftop gardens or decks. They can also provide great spots for installing solar panels for energy efficiency and cost savings.

Are Flat Roofs Better for Residential or Commercial Buildings?

While flat roofs are a great choice for both residential and commercial buildings – they are more common on commercial buildings. Being low maintenance and cost effective makes them an attractive option for companies building new commercial buildings.

However, the type of flat roof you will need to install depends on the size and shape of your building, as well as its location and climate. Be sure to consult a professional roofer to determine the best type of flat roof for your building.

Pros of Flat Roofing Systems:

Affordability: Flat roofing systems are often less expensive than sloped roofs because they require fewer materials and less labor to install. This makes them a cost-effective option for many building owners.

Easy to Maintain: Flat roofs are generally easier to maintain than sloped roofs because they are easier to access. This makes them ideal for buildings with HVAC systems or other rooftop equipment that requires regular maintenance.

Space Utilization: Flat roofs offer additional usable space that sloped roofs do not. This can be utilized for a rooftop garden, patio, or even additional living space in the case of residential buildings.

Energy Efficiency: Flat roofs can be designed with a reflective coating or other materials to improve energy efficiency. This can help reduce heating and cooling costs, making them a sustainable option.

Design Flexibility: Flat roofs offer more design flexibility which allows for a variety of shapes and sizes. This makes them a great option for creative or unique designs.

Low Profile: Flat roofs are low profile and unobtrusive, making them a great choice for buildings in areas with strict height restrictions.

Environmentally Friendly: Flat roofs can be designed to maximize energy efficiency and reduce the building’s carbon footprint. They can also be designed to collect rainwater for reuse or repurposing.

Cons of Flat Roofing Systems:

Susceptibility to Leaks: Flat roofs are more susceptible to leaks and water damage because they have less drainage. This can lead to problems such as pooling water, which can cause leaks and eventually compromise the roof’s structural integrity.

Lack of Aesthetics: Flat roofs are not as aesthetically pleasing as sloped roofs. This can be a drawback for buildings that require a certain visual appeal such as in historic areas or residential neighborhoods governed by an HOA.

Limited Lifespan: Flat roofs typically have a shorter lifespan. This is because they are more susceptible to water damage and require more frequent maintenance.

Drainage Issues: Flat roofs require a proper drainage system to prevent water damage. If this system is not built correctly, water can pool on the roof which can lead to leaks and other issues.

Higher Risk of Damage: Flat roofs are more susceptible to damage from hail, high winds, and debris. This can lead to costly repairs or even the need for a complete roof replacement.

Inability to Support Heavy Loads: Flat roofs can be susceptible to sagging or other structural damage if they are not designed to support the weight of heavy objects on the roof. This can be a concern for buildings with large amounts of rooftop equipment.

Consult With a Local Roofing Pro

In conclusion, flat roofing systems offer several advantages including affordability, easy maintenance, space utilization, and energy efficiency. However, they also have some drawbacks such as susceptibility to leaks and water damage, lack of aesthetics, and potential drainage issues.

When considering a flat roof, it’s important to weigh the pros and cons carefully to make an informed decision that meets your specific needs and requirements. Consulting with a professional roofing contractor like SJ Roofing can help you correctly pick the type of flat roofing system best for your budget and needs.

Contact SJ Roofing today for a free estimate on your flat roof.

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St Joseph’s Roofing is the #1 licensed and insured roofer in Northern Virginia’s for all your residential and commercial roofing needs. Our estimates are free and our work is world-class.

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