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What is TPO Roofing?

TPO roofing is a style of rubber roofing made from a thermoplastic membrane. If you’re wondering, what does TPO stand for, that would be thermoplastic polyolefin. TPO is created by bonding polypropylene and ethylene-propylene rubber using fiberglass, carbon filler, and other additives and stabilizer. While a typical flat roof is renowned for developing leaks, the lightweight TPO material is durable and watertight to ensure a low maintenance, leak-free roof for your building. More often than not, if you see a bright white roof in your area, it’s a TPO roofing installation

While TPO’s only been around since the 1980s, it is one of the fastest-growing roofing systems for commercial roofing and homes with a flat roof. TPO membranes are made from non-toxic, non-hazardous materials with no added plasticizers, making it an earth-friendly option that’s easily recyclable. While an EPDM roofing installation is more prevalent on existing roofing systems, more and more consumers are choosing TPO roofing for new installations because of the advantages it offers over the traditional singleply roofing. 

Benefits of TPO Roofing vs EPDM Roofing

One of the main advantages of this single ply membrane system is the price. TPO roofing cost can be as low as $5.50 per square foot, which is often cheaper than a new EPDM roofing system. The average cost of TPO roof maintenance is also lower since it’s more resistant to damage. You can save even more money by installing your TPO roofing directly over your existing roofing, so long as there isn’t extensive water damage or a loss of structural integrity. 

While TPO and EPDM are both made with a water-resistant roofing membrane, a TPO roof system has fewer seams, so there is even less chance of failure. These seams are welded in place, making them stronger than EPDM seams. TPO is also highly puncture-resistant and resilient against tears or abrasion, which means it’s much safer to walk on your roof, and a falling limb is less likely to penetrate the membrane.

TPO is also much more effective at reflecting UV rays than an EPDM roof. A TPO roof can reflect nearly 90% of UV rays away from the building, which will prevent wear and tear on your roof and keep your cooling bills lower. This means you can expect a life span of 20-30 years from your TPO roofing system, and with proper maintenance, it can last even longer. 

With fire season stretching longer and longer each year, protecting your home from fires should always be at the top of your mind when upgrading your roof. TPO roofing can be manufactured with fire-retardant chemicals that protect your home or business from the spread of wildfire or neighboring structure fires. 

Selecting your insulation

When it comes to TPO roofing installation, you have the freedom to choose the insulation material that best suits your needs. The insulation material is attached directly to the decking, and it is designed to help your house maintain a steady temperature. Your roofing contractor can go over the benefits of various insulation materials and help you make a decision that works with your budget. 

The most common insulation type for roofing applications is Polyisocyanurate. It’s pricier but pays off with a higher R-value rating. Extruded Polystyrene is a mid-range semipermeable insulator. Expanded Polystyrene is another option that offers the best value but doesn’t perform quite as well. The insulator can fully adhere to the base for maximum energy efficiency, or it can be attached with mechanical fasteners for a simpler installation. Additionally, you should consider adding a vapor barrier to protect the insulation from condensation that occurs when the cool air in your building meets the warmer air near your roof. 

Installation materials 

You’ll also need to select the thickness of your TPO membrane. The thickness is measured in mils. One mil is a thousandth of an inch, and the typical thickness ranges from 45 mil to 90 mil. While 60 mil is the most common thickness, many roofs are fine with a 45 mil membrane, as long as you don’t expect many people to walk on it or frequent hail storms. Thicker TPO typically provides a longer service life, but improper installation or poor maintenance can still lead to roof failure. It’s also crucial that you choose a brand with a good reputation, as the quality can vary significantly, no matter what thickness you choose. 

TPO also comes in a variety of colors. Since most flat roofs aren’t visible from the ground, most people select from the standard color options of white, grey, or tan roofing. But if your roof has a higher profile or it will be visible from certain parts of your building, you can choose from premium color options or customorder specific colors to improve your building’s look. These colors can cost you an extra 15% per square foot of your roofing material.

Choosing your installation style

If you decide to purchase a thermoplastic membrane roof, you’ll still have a few decisions to make. There are different advantages and disadvantages of using mechanical fasteners, a ballasted system, or chemical adhesives to attach the TPO roof membrane. It’s best to consult a roofing contractor to help you weigh the pros and cons of each system. 

Mechanically attached roofs are held in place at the seams with fasteners attached to the roof decking. The seams are welded to the fasteners for a secure attachment. This option is cheaper and faster to install, and it doesn’t require a warm day since you won’t be using chemical adhesives. However, the roofing membrane will only be attached at the seams. Wind or pressured air coming from inside your building can cause the membrane to billow up, leading to condensation and moisture build-up on your insulation and eventually mold.

A fully adhered membrane installation is more expensive to install, and it requires a warm day to keep the adhesive and membrane ready to work together. During installation, a chemical adhesive will fully bond each part of the membrane to the substrate, creating a more secure and energy-efficient barrier for your roof. Unless you’re on a strict budget, this is the much better option for your TPO roof installation.

When to consider EPDM roofing

Now that you know what is EPDM roofing, as well as TPO roofing, you can weigh the two options. If you plan on remaining in the building beyond the typical 20-30 year lifespan of TPO roofing, it can be a worthwhile investment to consider choosing EPDM. EPDM rubber roofing can last up to 50 years, rivaling metal roofing in longevity and durability. However, unless you pay the premium to get the white coating, the roofing material will be black. It will absorb a lot of extra heat in the summer and can increase the cost of your cooling system. 

TPO membranes have a laminate surface that makes them a little bit stiff. On the other hand, EPDM is very flexible and can shift and move with your house over the years. TPO roofs are more prone to cracks as they age, and that is the primary reason they don’t last as long. 

While TPO roofing is great at reflecting heat, it’s not able to withstand long periods of high temperatures as effectively as an EPDM membrane can. EPDM roofing can tolerate temperatures of up to 200 degrees without worry. And because this style of roofing is older than TPO, the formula is consistent and proven. TPO formulations can vary from batch to batch and manufacturer to manufacturer, which means you have to source your material from someone reliable to prevent early failure. 

Experience you can count on

TPO roof installation can be very delicate work. It requires experience and skill to ensure you don’t make any mistakes that can compromise your entire building’s structure. Installing the seams requires a hot weld. Done right, and your roof is secure against leaks; done poorly, it might not be watertight. Even a small leak can lead to mold, rot, and other issues if it isn’t addressed quickly. That’s why it’s crucial that you leave all of the TPO roofing details to the pros.

Preman Roofing Solar is a San Diego roofing company that has installed and maintained thousands of roofs in the area since 1999. We are a full-service roofing company that offers new roof installations, TPO roof repair, inspections, and solar energy system installations. We are more than happy to guide you towards the best roofing system for your commercial or residential roofing needs, and all of our quotes and appointments are guaranteed. 

That means once you see a price, you won’t be surprised with any hidden fees or sudden expenses. You’ll also know exactly when to expect us and how long the job will take so you can make any preparations needed to be comfortable while we work on your roof. To learn more about our roofing service or schedule a free estimate, contact us today.