Flat roofs are very common on large commercial buildings and warehouses. There are a number of different types of flat roofs that can be installed on these types of buildings. The key is knowing which one will best suit your needs and budget. For the most part, a rubber membrane roof is the highest value option in terms of durability, longevity and installation cost. The issue is knowing which type of rubber membrane roof will be the ideal choice for your needs. There are two main types of rubber membrane roofing materials to choose from: Thermoplastic Olefin, known as TPO, and Ethylene Propylene Diene Monomer known as EPDM. Each one has its own benefits and drawbacks when used as a flat roofing material for buildings in the Vancouver area. Lets take a look at how TPO and EPDM roofs compare according to things like cost, durability and longevity, maintenance and efficiency.
Durability & Longevity TPO vs EPDM
To start, both of these roofing materials are designed to last for decades so long as they are properly installed. Like most roofing materials, improper installation will lead to premature deterioration and the added costs of repairs and possible replacements. When it comes to the durability of each rubber roofing membrane, it starts with the thickness. A thinner membrane made of either TPO or EPDM will not last as long as one that is thicker. Beyond thickness, the factor that most affects the lifespan of a rubber membrane roof is how well the seams are attached together. If a seam is improperly closed, water will almost certainly get under the roof and cause major issues like leaks and structural damage. Although TPO is a newer material, the strength of its seams compared to EPDM seams is three to four times stronger. This however, does not mean TPO is all together stronger than EPDM.
Since it is a newer material, there is no existing TPO roof that is older than 15 years. This doesn’t mean a TPO roof won’t last for multiple decades as it was designed. Due to reformulations of the product to improve its structure, there just aren’t any examples of TPO roofs that have been in existence for more than 15 years. EPDM roofs on the other hand have been available for much longer, and there are plenty of examples of roofs built using EPDM material that are up to 25 years old and still completely intact. With properly installed seams and flashing, an EPDM roof will have no problem lasting up to 25 years. Furthermore, EPDM roofs have proven to last longer in colder climates, which should be a consideration for any commercial property owner in the Vancouver area.
Roof Maintenance TPO vs EPDM
For the most part, these single ply roofing membranes require little maintenance over their lifespan. In cases where maintenance is required, it will likely have to do with the roofing seams. EPDM roofs are more likely to require some type of maintenance over their 25 year lifespan because of the way the seams are attached. Unlike a TPO roof, where seams are hot-air welded together creating a permanent seal, EPDM roof seams are treated with an adhesive. This makes them more likely to come apart, particularly if the seams were improperly closed upon installation.
In cases where TPO roofs do happen to require maintenance or repairs, it is much more difficult to weld new materials to the existing roof. Over time, the TPO roof will naturally deteriorate due to exposure to the sun and other elements. This makes the membrane lose pliability and thermoplastic capabilities, meaning an activator is required to make it possible to attach new material to the old membrane. In the case of EPDM, repairs and patches are more easily accomplished, and require no special activators.
Cost & Efficiency TPO vs EPDM
Since they feature newer technology, TPO roofs usually will cost more to install compared to EPDM roofs. No matter which roof you choose, it will cost more upfront to get a thicker membrane, but the thicker the roof, the longer it will last. In terms of energy efficiency, the TPO roof will likely help you save more in the long run compared to an EPDM roof. This is due to the newer built in reflective technology that prevents solar heat absorption. While there are EPDM roofs that are available in light reflective colours like white, they still cannot replicate the built in reflectiveness of a TPO roof, an therefore cannot offer the same energy savings.
No matter what type of roof you choose, the roofing team at Coast Mountain Roof will be sure to provide you with top quality roof installation, so you can rest assured you will get the most out of your new flat commercial roof. To learn more about our commercial roofing services, or to book a free consultation for your upcoming project, be sure to contact Coast Mountain Roof today!
Brad Gordon and his team of professionals have been installing roofing, waterproofing and architectural sheet metal systems in the Greater Vancouver area for over 20 years.