The Slippery Truth About Common Roofing Materials

Is Your Commercial Roof an Ice Rink Waiting to Happen? New Research Uncovers Shocking Causes of Slip and Falls

 

Buckle up – we are excited to share valuable groundbreaking insights that will change how you think about commercial roofing safety.

 

Here at Triton Inc., safety is the foundation of everything we do. As a trusted leader in roofing for over 50 years, we are dedicated to the safety of our contractors and clients. For too long, the roofing industry has acknowledged the inherent risks of working at height, often focusing on falls off the roof. After learning that slip-and-fall incidents consistently rank among the most costly workers’ compensation claims, we determined it was unacceptable and insisted on proactive, science-backed solutions. That’s why, in 2024, we proudly partnered with Iowa State University to fund a groundbreaking safety study on roofing materials. The results are in, and we’re diving deep into the findings of this crucial study on slips and falls on commercial and industrial flat and low-slop roofs.

 

This research shines a much-needed light on a frequently overlooked danger: slips and falls on the same level as a flat commercial or industrial roof. This type of incident has historically been under-researched and analyzed, often even accepted as a part of the job. But we thought – what if we could significantly reduce these frequently overlooked risks?

 

We dove into the details in our recent podcast “Roofing Uncovered – Episode 3 – Iowa State University (ISU) Roof Slip and Falls Study”. Scroll down to watch/listen to the detailed podcast – or continue reading below for a summary.

 

The Slippery Truth About Common Roofing Materials

The podcast highlights that roofing often carries the highest insurance and workers’ compensation policy costs in the entire construction sector, and it also accounts for the highest number of injury lawsuits and settlements. Why is this the case? The answer, in large part, lies in the common roof materials. Today’s most common commercial roofing membranes are smooth PVC, smooth TPO, and silicone, which the study has proven are extremely slippery when wet due to rain, dew, frost, snow, ice, or even HVAC condensation. Imagine an outdoor ice skating rink on top of a building, which is the potential reality for anyone walking on a wet roof with these smooth roofing materials.

 

The podcast provides alarming real-world examples from OSHA records with detailed cases as examples. These incidents can lead to substantial financial burdens through medical bills, lost wages, and even future wage loss coverage due to long-term disability. Lawsuits can target both the building owner and the contractor if negligence in safety precautions can be proven.

 

Iowa State University’s Groundbreaking Research

Recognizing the severity of this safety issue, Iowa State University agreed to conduct a comprehensive scientific research study in 2024. This study, led by Dr. Richard Stone, investigated nine common commercial roofing materials, analyzing the impact of material type, coefficient of friction, shoe type, and surface smoothness on slip resistance. The findings were revealing:

 

Material Type:

Material type had the strongest effect on slip resistance, significantly more than shoe type. In fact, the study found that the type of shoe (tennis shoe vs. non-slip work boot) had no meaningful effect on performance.

 

Textured vs. Smooth Thermoplastics

Textured vs. Smooth Thermoplastics Textured TPO and Textured PVC significantly outperformed smooth versions regarding slip resistance. The study meticulously measured various slip events, including micro slips, slides, and actual slips and falls. The results showed overwhelming evidence for the difference between smooth and textured thermoplastics. Quantifiably, the use of textured thermoplastics resulted in an average of a 55% decrease in micro slip events, an 80% decrease in slide events, and a 100% decrease in slip and fall events compared to smooth thermoplastics. (We exclusively offer textured thermoplastics.)

 

Coefficient of friction

Standard lab tests for the coefficient of friction showed a weak correlation with actual real-life performance. For instance, silicone can test with a high coefficient of friction when wet but still be very slippery to walk on.

 

Best and Worst-performing materials

The best-performing materials were a modified bitumen cap sheet with granules, a rubberized spray-applied rubber membrane, and Textured PVC and Textured TPO. The three worst-performing materials were smooth silicone, smooth TPO, and smooth PVC, which were the only materials participants walked on and actually slipped and fell (under controlled safety conditions).

 

 

Summary and Recommendation

These findings of the Iowa State University study are industry-shattering. The research provides concrete evidence of the significant risks of walking on common smooth commercial roofing materials when wet. It highlights the clear safety advantages of textured alternatives. This research presents a compelling case for industry-wide change in the roofing industry, where millions of square feet of smooth, slippery membranes are installed annually.

 

The ISU research reveals that higher friction surfaces lead to lower slip and fall events and increased worker confidence, which, in turn, should decrease workers’ compensation claims. The study goes on to recommend the implementation of textured materials as the minimum standard for safety on commercial and industrial roofs.

 

At Triton Inc., we are committed to prioritizing safety on every project. We believe this research should be at the forefront of industry discussions, prompting a shift towards safer material choices on all roofs.

 

We are dedicated to the safety of all contractors and clients and hope we can all move towards a future where slips and falls on flat roofs are no longer an accepted risk but a preventable occurrence. By embracing textured membranes, we can collectively work towards reducing the alarming rates of slip and fall injuries and the associated financial burdens. Most importantly, we can ensure that everyone who walks on a commercial or industrial flat roof returns home safely to their loved ones.

 

We invite you to explore these findings further by listening to the full podcast episode and visiting our website to learn more before your next commercial roofing project.

 

Click here to see the graphs and read more on the Slips & Falls Research and watch the detailed podcast episode below.

 

PVC vs. TPO: Uncovering the Differences in Commercial Roofing Membranes

What are PVC and TPO?

First, let’s establish some basic definitions. Both PVC (polyvinyl chloride) and TPO (thermoplastic polyolefin) are thermoplastics, meaning they can be repeatedly softened by heating and hardened by cooling, allowing them to be heat-welded together. This heat-weldability is a key advantage of thermoplastics in roofing.

While both are thermoplastics, PVC and TPO differ significantly in many areas. PVC: As the name suggests, PVC contains chloride and is derived from oil, consisting of various polymers and additives. Think of a pool liner, to understand PVC’s flexibility. TPO: TPO is often described as an elastomer-modified polypropylene, essentially polypropylene with a synthetic rubber component (ethylene polymer). While also a thermoplastic, TPO tends to be stiffer and harder than PVC.

 

Fire Retardancy

PVC naturally possesses exceptional flame retardancy due to its chlorine content. TPO, on the other hand, relies entirely on added fire retardants to achieve flame resistance. This makes PVC a potentially better choice for industrial sites with higher fire risks. Click here for a fire test video.

 

Flexibility and Weldability

PVC is inherently more flexible and generally easier to weld due to its softer nature, providing a visual “bleed” during welding that indicates proper fusion. TPO, being stiffer, doesn’t offer this visual feedback, requiring more careful attention to temperature and technique to avoid “cold welds”.

 

Chemical Resistance

PVC exhibits superior resistance to a wider range of chemicals, including animal fats, food grease, oils, lubricants, and hydrocarbons. TPO does not hold up as well in these environments – therefore, PVC is often recommended for environments like restaurants and food production facilities where such chemical exposure is likely.

 

Environmental Considerations

However, PVC contains chlorine and plasticizers, which have raised environmental concerns regarding disposal in landfills if not properly recycled. TPO does not contain these substances, giving it an environmental advantage in that regard. Both PVC and TPO are recyclable.

 

Scrim (Reinforcement Layer)

Both PVC and TPO membranes have a reinforcing scrim layer between the top and bottom plies. However, PVC typically uses a non-wicking scrim, meaning it doesn’t absorb water…. TPO generally uses a low-wick scrim, which can absorb some moisture if the edge is cut and exposed, requiring the use of cut edge sealants.

 

Flexibility and Weldability

PVC is inherently more flexible and generally easier to weld due to its softer nature, providing a visual “bleed” during welding that indicates proper fusion. TPO, being stiffer, doesn’t offer this visual feedback, requiring more careful attention to temperature and technique to avoid “cold welds”.

 

Cost, Longevity and Quality

PVC has a longer track record in the commercial roofing industry, dating back to the 1960s in North America. While TPO was introduced in the 1990s and has seen significant advancements, its long-term performance can be more variable depending on the manufacturer and formulation. As we note in our “Roofing Uncovered” Podcast (Episode 4 PVC vs. TPO), in the US market, TPO is often the lowest-cost option, while in Europe, high-quality TPO can be more expensive than PVC due to different formulations and material usage.

 

Smooth vs. Textured Thermoplastics

In a recent University study, Textured Thermoplastic membranes emerged as a critical minimum for roof safety, while materials like smooth TPO, PVC, and silicone performing the worst in the study. As highlighted in Episode 3 “Roofing Uncovered” podcast (Episode 3 – Iowa State University (ISU) Roof Slip and Falls Study), both smooth TPO and PVC membranes are extremely dangerous when wet, behaving like “ice skating rinks”. This is a critical safety concern that we at Triton Inc. take very seriously. This is why, we only supply textured thermoplastic membranes. These textured surfaces offer significantly improved slip resistance, even in wet or icy conditions, drastically reducing the risk of slips and falls. Click here to learn more about the Research Study.

 

Which One Wins? It Depends.

Ultimately, the “winner” in the PVC vs. TPO debate depends on the specific needs and priorities of your project.

Consider PVC for projects requiring exceptional chemical resistance, inherent fire retardancy, ease of repair, and a long, proven track record, especially in demanding environments. Consider TPO as a potentially cost-effective and environmentally conscious option, but be sure to research the manufacturer’s quality and track record.

 

At Triton Inc., our focus is on providing safe and durable roofing solutions. We encourage you to carefully consider the unique characteristics of each material and, most importantly, to prioritize safety by choosing textured thermoplastic membranes for enhanced slip resistance.

 

Contact us today to discuss your specific roofing needs and explore our range of high-quality, textured, slip-resistant PVC and TPO options.

 

Click here to learn more about our slip-resistant PVC. 

 

Click here to learn more about our slip-resistant TPO.

 

 

 

 

 

 

TPO and PVC: Thoughts & Concerns

Over the last decade, TPO (thermoplastic polyolefin) roofing membranes have become the most popular choice for flat and low-slope roofs. They are even used for roof recovers and attached over old roofs. PVC (polyvinyl chloride) is also a thermoplastic membrane that was the dominate single-ply until the recent rise of TPO. Thermoplastics are strong materials and typically produced in reflective white colors. They comes in rolls and are mechanically attached with fasteners into the deck, fully adhered using glue and adhesives, or heat-welded to induction plates that fasten the insulation or cover board down. The seams are overlapped and welded together with hot air. Typically, TPO and PVC welds hold strong over time. It is supplied in 60 mil (1.5 mm), 72 mil (1.8 mm) or 80 mil (2 mm) thick sheets, though a portion of the thickness is taken up by the reinforcement scrim. There is thermoplastic polymer material, which is the actual waterproofing, above and below this scrim. The thickness above the scrim depends upon the manufacturer and the quality of their TPO or PVC.

Some manufacturers, such as Duro-Last and Fibertite, are even selling 40 mil thick sheets. In this instance, they state in their literature there is only 17 mils of PVC polymer above the scrim. This means you only have 17 mils of waterproofing to withstand UV, ponding water, and the elements before the scrim is exposed.

TPO became popular for many reasons, mostly economical, as it is the cheapest rolled roofing membrane in the market. It is lightweight, safe to install, durable, and energy efficient. No open flames, and no hot kettles. You could lay insulation board or hard board over an old roof, or use fleeceback membrane, and then roll out a TPO or PVC for a completely new, warranted system. However, most of the time this requires thousands upon thousands of fasteners to go through the old roof and the old deck in order to hold it down. Every seam must be welded perfectly, every flashing done correctly, and everything sealed with caulk in order to prevent the creation of a water bed.

The photos below I took in Las Vegas recently on a 14-year-old TPO roof. You can see where the UV rays had been reflecting off of the parapet wall onto the field. What happens is a magnifying effect. The UV that bounces off the wall is more intense and deteriorates the TPO membrane faster. Remember, there is only 15-23 mils on average of material before the scrim is exposed. The scrim can then absorb water and moisture can actual wick through the scrim. This not only causes leaks but accelerates degradation of the rest of the sheet.

TPO became popular due to the discovery that PVC roof membranes had, under ponding water, their plasticizers “migrate”. This means the plasticizers that comprise the PVC polymer structure actually move out of their originally intended position. The result is brittleness and loss of stability. However, this greatly depends on the manufacturer and the type of plasticizers they use and how they are integrated during manufacturing. Plasticizer loss has been studied and analyzed extensively by prominent PVC manufacturers, such as our partner, Protan. I also want to note aged TPO is difficult to weld new TPO to. The welds typically don’t hold, so it must be repaired with tapes or peel-and-stick TPO. Protan PVC, on the other hand, can still be heat welded even after 30 years of service.

The other issue that led to the rise of TPO was the ease of welding during installation Plus, they are much cheaper! It would make sense that TPO is the way to go, right? Unfortunately, you get what you pay for. TPO membranes are struggling to last 10 years in many instances as the TPO polymer materials are not as strong, durable, and long-lasting as PVC. Many of you have likely experienced this firsthand. TPO manufacturers continue to modify and play with their formulations, whereas the highest quality PVC formulations haven’t changed in decades and have proven, documented lifespans.

PVC membranes do have their place in the market, despite some issues and maintenance requirements to ensure watertight performance. They are the most chemically-resistant rolled roofing membrane, lightweight, safe to install, and have predictable life expectancies. Triton believes in full roof replacement situations, or for new construction, PVC single-ply membranes are the best choice. A major downside to both TPO and PVC membranes is the smooth, slippery surface. When wet with dew or rain, this leads to a high number injuries from slips and falls. Triton has changed that by providing the only high-friction thermoplastic membrane in the industry through our partnership with Protan.

All of this proves why liquid-applied membranes are continuing to rise and gain a much larger footprint in the roofing industry. For restoring an existing roof membrane, a liquid membrane like ours makes the most sense. Unless, of course, the existing insulation is saturated or the old roof is completely shot and a tear-off is the only option. As these TPO roofs show signs of premature failure, a lot of money is being saved by being pro-active and restoring them with our TritoFlex 2K thermoset set rubber system.

If you’re interested in learning more about our stronger, safer, and sustainable approaches to roofing, reach out to me anytime.

 

Roof Certifications – The difference between FM, UL, and ASTM

The Slippery Truth About Common Roofing Materials

PVC vs. TPO: Uncovering the Differences in Commercial Roofing Membranes