5 things you need to know before choosing a TPO roofing membrane

TPO membranes have been on the rise since its introduction in the 1990s as a waterproofing system for flat and low slope commercial roofs. They offer a combination of energy efficiency, durability, cost-effectiveness, ease of installation, environmental benefits, and design flexibility.

However, not all TPO membranes are created equal. There is a big variety of TPO membranes in the market, with varying degrees of quality. Let’s look at some key aspects to consider before choosing a TPO roof membrane:

TPO (Thermoplastic Polyolefin) is a type of single-ply synthetic roofing membrane. It is typically composed of 3 layers: a TPO polymer base, a polyester-reinforced scrim, and a TPO compounded top ply. It combines the flexibility of rubber with the heat-weldability of a thermoplastic in a flexible sheet with excellent lay flat characteristics. This makes it particularly suitable for medium and large-size commercial and industrial roofs.

TPO membranes are typically available in reflective white or light-colored options. Their reflectivity helps reduce heat absorption and can contribute to improving the energy efficiency of the building. In warmer climates, this can lead to lower cooling costs, particularly in buildings that have moderate or no roof insulation layer.

TPO roofing membranes are an environmentally friendly roofing option as they are free from harmful substances such as chlorofluorocarbons and halogens. They also require less energy during manufacturing than other types of membrane. 

The sustainability of any roofing membrane, however, is proportionally linked to its longevity. The durability of a TPO membrane can vary significantly, depending on the quality of its formulation. A high-quality TPO membrane is estimated to have a lifespan of between 25 and 30 years.

TPO is also suitable for use under green, solar and blue roofs. These types of installations enhance the sustainability of any building.

TPO membranes are available in different sizes and thicknesses for flexibility in design and ease of installation. They can be fully adhered, ballasted or mechanically attached to the support. Seams between adjacent membranes are welded together using a hot-air welding machine, which bonds the top and bottom sheets together, delivering consistent seam quality and high strength. Details around roofing elements such as chimneys, air-conditioning equipment and skylights can be easily done with specific flashing accessories. In addition, installation is completely flame-free, which results in safer working conditions.

On refurbishment projects, TPO membranes can be installed directly over most existing roofing systems. This eradicates the need for tear off, significantly minimizing construction waste.

TPO membranes need very little maintenance. A twice-yearly roof inspection is in most cases enough to spot any issues. As with any light-coloured membrane, however, TPO will eventually get dirty and a loss of reflectivity will inevitably happen over time. It is estimated that between 30-50% of the membrane’s reflectivity is lost in the first 3 years after installation, so regular cleaning might be necessary.

TPO membranes are also easy to repair, even after several years of direct UV exposure.

The Elevate UltraPly TPO roofing membrane was introduced in 1996, with a premium chemical formulation that has remained unchanged since the beginning. Its base polymer is made from the incorporation of ethylene propylene rubber into a thermoplastic matrix of polypropylene. This results in a membrane with outstanding elastomeric and thermoplastic properties. UltraPly TPO does not contain chlorine, halogens or plasticizers that can migrate from the sheet in the long term. 

The high-quality formulation of UltraPly TPO allows it to withstand UV and ozone weathering and heat degradation from the manufacturing process onwards. The correct balance between fire retardants, antioxidants, UV stabilizers and polymer content also has an important impact on the weldability of the membrane.

Installation of UltraPly TPO is very straightforward. The same membrane can be used for all roof areas (main roof area, upstands, etc), all applications (green roofs, solar roofs, etc) and all types of systems. Its wide welding window enables it to be installed year-round and it can be used both on new roofs and on refurbishment projects. UltraPly TPO is available in thicknesses ranging from 1.1 to 2 mm, and rolls up to 3.05 m wide by 30.5 m long, allowing a fast and cost-effective coverage. 

Having successfully passed the EN 13948 test for resistance to root penetration, UltraPly TPO is perfectly compatible with green roof systems and can also be combined with any type of PV installation due to its reflectivity, high-temperature resistance and outstanding wear and tear resistance.

Due to its stable and consistent formulation and the presence of the correct amount of antioxidants, UltraPly TPO is easy to repair, even after several years of exposure. Membranes in service only require proper cleaning with a solvent-based cleaner prior to welding.

UltraPly TPO is also easy to recycle. Since it does not contain halogenated flame retardants, chlorine, heavy metals or plasticizers, it can be easily grounded and incorporated into the bottom ply to produce a new membrane, resulting in a 100 % reuse of recycled material.