TPO Roofing: Pros, Cons, and Cost

Find out everything you need to know about TPO roofing, including cost, installation methods, and whether it is the right roofing material for you.

Cameron Bates
Updated Dec 19, 2022
·
7 min read

If you are in the market for commercial-grade roofing, TPO may ring a bell. Since its introduction, this relatively inexpensive rubber roofing material has been making big waves in the industry and is now seen on commercial buildings all over the country.

While the verdict is still out on TPO roofing, some of its qualities such as energy efficiency, cost-effectiveness, and easy installation make it hard to ignore.

Keep reading to find out whether TPO roofing is suitable for your roof.

Get a TPO roofing quote from a local pro

On this page

What is TPO roofing?

Thermoplastic polyolefin, or TPO for short, is a roofing material consisting of a white single-ply membrane composed of various synthetic components and a fabric reinforcing scrim. Over the last several years, TPO has become a staple in the roofing industry, especially for commercial roofing systems.

Like many other roofing materials, TPO’s white membrane reflects heat rather than absorbs it. TPO’s ability to reflect ultraviolet rays (UV) allows the rooms below to stay cooler and conserve energy.

While TPO is mainly known for its use on flat commercial roofing systems, it is also a viable option for residential buildings.

TPO roof options

Color range

With TPO membrane primarily used on flat roofs of commercial buildings, the material's color range and general aesthetics are often not of significant concern. That is why TPO roofing doesn’t offer a lot of variation in terms of color, with white, black, and grey being the main options.

While there are other color options available, the majority of TPO membranes that you will come across will be white. This is due to white TPO roofing systems offering the most benefit with both energy efficiency and UV resistance.

Thickness

Along with having different color options, TPO can also come in a variety of different thicknesses. TPO is typically offered in 45 mil, 60 mil, and 90 mil, but this selection can change depending on the manufacturer and your location.

Generally speaking, commercial-grade TPO will have a thickness of up to 90 mil to help with its durability and longevity. In contrast, residential TPO can have a thickness of between 45 and 60 mil.

TPO membrane thickness is selected on a project-specific basis, with both conditions and requirements considered. For example, a thicker TPO membrane should be considered for a large commercial building that will experience heavy traffic on the roof.

What is single-ply membrane roofing?

As the name implies, single-ply membranes are made of a single waterproofing sheet of rubber and other synthetics. These sheets are then either ballasted, fully adhered, or mechanically fastened to a layer of insulation to form an eco-friendly and durable protective layer on your roof.

In the world of commercial roofing, there are two main categories of single-ply roofing membranes: ethylene propylene diene terpolymer (EPDM) and thermoplastic polyolefin. Not only do these two single-ply membranes differ in their material makeup, but also their energy efficiency and installation methods.

While single-ply roofing membranes can be used in various settings, they are best situated for commercial buildings with low-sloped or flat roofs.

TPO roofing installation methods

There are two primary options for attaching a TPO membrane to your roof.: mechanically fastened and fully adhered. Both installation methods will differ in cost, timeliness, and effectiveness.

Mechanically fastened

Mechanical fastening is the most common installation method for TPO roofing membranes. With this method, the roofing material is laid down directly on the insulation boards with screws driven through into the metal deck below. Screws are drilled on every roll of the membrane seam to ensure everything is fastened securely. Each roll's edge is heat welded together using a hot-air gun to create a watertight seal.

Mechanical fastening is the timeliest and most cost-effective of the two main installation methods. This method is also preferred by most roofing contractors as the workmanship can be easily inspected and verified.

Fully adhered

A fully adhered roof is where the TPO membrane is glued directly onto either the insulation board or a cover board. This means that the roof insulation or cover board is solely responsible for securing the TPO membrane to the metal roof deck.

Roofing companies will often choose this method as it binds the entire membrane to the substrate rather than just the seams. This makes the roof more resistant to leaks and has a higher wind-uplift rating. However, this method, while being more expensive and slower than mechanical fastening, can pose more of a challenge due to temperature requirements and time constraints.

How much does TPO roofing cost?

TPO is one of the most cost-effective options available for commercial roofing. While the exact price will depend on several factors, such as TPO variation, size, roof condition, and installation method, you can expect to pay between $3.50 and $9.50 per square foot. An entire TPO roof can cost anywhere from $6,000 to $18,000.

Pros and cons of TPO roofing

Pros

Cost-effective

TPO is becoming an increasingly popular roofing material because of its affordability. While still offering many of the same benefits, TPO comes at a much lower cost than other commercial roofing options, such as PVC.

With a low upfront cost, TPO roofing can also provide you with considerable energy savings in the long term.

Easy installation

Due to TPO being a lightweight and flexible material, installers find it very easy to maneuver compared to other roofing options. The wider sheets of TPO also mean that fewer are required to be drilled in and sealed. This results in an easier and faster installation process and significantly lowers labor costs.

Energy efficient

Rather than absorb the UV rays as many other materials do, the white TPO single-ply membranes will reflect the UV. With TPO’s reflective properties, the rooms below are naturally kept cooler during the warmer months, and you won’t use your AC as often. This not only creates a more energy-efficient building but will also simultaneously lower your electric bill.

Eco-friendly

There are a few reasons why TPO is an environmentally friendly roofing solution. Firstly, the material is 100% recyclable, allowing used TPO to be reworked and made into new roof sheets.

Another eco-friendly property of TPO is that it does not contain chlorine, a hazardous chemical found in many roofing materials. This means that TPO will not emit toxic fumes in the case of a fire.

Cons

High heat spells trouble

While TPO can cut your energy costs and keep the rooms below cooler, it struggles when exposed to extreme heat or high solar loads. This issue has arisen mainly in the southern states, where temperatures are generally higher throughout the year. If you live in an area prone to experience extended periods of extreme heat, then there may be better options than a TPO roof.

Longevity

With TPO being a relatively new roofing product, many questions remain about its longevity and whether it will stand the test of time. The chemical formula for TPO is still a bit of an unknown, as manufacturers are continuously changing and developing the product. Previous TPO variations have caused some concerns with seam failures and membrane punctures.

While this does not necessarily mean that the current product will have a short lifespan, it is impossible to tell how it will perform in the long run. To be on the safe side, you should look for manufacturers whose products and the formula are proven to stand up against the test of time.

Is TPO roofing the right option for you?

You first need to understand when exactly a TPO roof is necessary. TPO is designed for flat or low-slope roofs, but in some cases, it can be required by building codes.

If your roof has a pitch below 2:12 (less than two vertical units up for every 12 horizontal units out), it will require a TPO membrane or another type of flat roof system, according to building codes.

But, as for whether or not TPO is the best flat roofing system, factors such as the low price point, benefits in energy efficiency, and little to no maintenance make it a compelling argument.

Despite the question marks surrounding its longevity and product development, TPO still has a lot to offer and is absolutely worth your consideration.

Hire a local pro to install your TPO roof today