Does Walking on A Flat Roof Damage It? – Explained by expert!

Flat roofs are making quite a big comeback these days due to their stylish and functional design. But despite having great functionality, they aren’t immune to damage under severe pressure build-ups. That brings up the question, does walking on a flat roof damage it

Walking on a flat roof will not necessarily damage it instantly. But it may weaken the infrastructure and damage the pressure points. And if that happens, there’s the possibility of heavy damage later on.

It’s important to find out what happens when you walk on flat roofs to know why it’s considered bad. So, let’s have a look into how flat roofs work and what may cause them to collapse in the future. 

What Type of Roofing Is Used for A Flat Roof?

Water damage and impact resistance – these two are the main roofing material criteria for flat roofs. Here is a short overview of the most common materials to tackle these needs.


PVC (PolyVinyl Chloride) roofing is best known for its longevity and affordability. It contains a coating of durable weathering film and a flexible fiberglass mat on top of the bottom ply. 

And to top it off, it comes with an acrylic finish. It takes about 350 pounds per inch to reach the breaking point of these types of flat roofing. 


BUR refers to the Built-Up Roofs. These roofs contain multiple layers of ply sheets and cover boards bonded by asphalt and hot tars. 

Furthermore, the surface is topped off with rocks and gravel for an extra sturdy framework. Due to its multi-layer protection, it can withstand a much greater force than usual flat roofs like PVC or TPO. 


TPO is pretty much like a budget-friendly version of the PVC coating. It costs almost half the usual PVC roofing and is pretty resistant to heavy water damage.

However, TPO is a single-ply roofing system made with a very lightweight material. As a result, it’s good for homes that can’t withstand a heavy roof like BUR roofing. But that also means that it isn’t very effective against impact or pressure damage.

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Chemically, EPDM refers to Ethylene Propylene Diene Monomer. It’s practically a rubber roofing system that’s currently super popular among new homeowners. 

Its popularity is mainly due to the use of highly durable and long-lasting synthetic materials. It can also withstand a good amount of force due to elasticity. But that’s also its major weakness as extreme heat can weaken the structural integrity from within. 

Modified Bitumen

Finally, modified bitumen is also, well, a ‘modified’ version of the heavy-duty BUR roofing. It normally comprises polyester or fiberglass-reinforced fabric with a base coating of asphalt emulsion. 

Modified bitumen roofing certainly adds to the aesthetics of a home but it’s also the weakest out of the five. It has the lowest resistance against impact force and the fragile surface can easily break apart at minor inconveniences. 

Can A Flat Roof Hold Your Weight?

Whether a flat roof can hold your weight or not, depends directly on how much impact your roof can withstand. If the amount of force applied is greater than the impact resistance level, your flat roof may collapse upon walking. 

Take the resistance level of PVC roofing for example. You already found out that they can withstand up to 350 pounds of pressure per inch. So, what if you stomp on a PVC flat roof and end up going beyond that pressure limit? What do you think is going to happen?

Precisely. It will most likely collapse. The same concept stands true for all other types of roofing materials. Different materials have different impact resistance levels that decide their breaking point. 

And as for your weight, it eventually boils down to how much pressure you’re applying on the roof. That’s why it doesn’t matter even if you’re lightweight, your safety up there isn’t necessarily guaranteed. 

How Walking on A Flat Roof Might Damage It?

Walking or stomping usually damages the structural integrity of a flat roof. Here’s how walking on a flat roof can contribute to such rough conditions. 

  • Uneven Distribution of Force
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Do you know why people are asked to consistently run around when they get stuck in quicksand? Because as long as there’s even distribution of force on the sand, the surface level can’t break and drown you. 

Quite a similar concept works with flat roofs. Since it’s comparatively wide-spread, the full roof works together to create a surface tension of some sort. Not like a water surface, though.

Anyway, while walking, if you stand still and firm, you can create an imbalance in this surface tension. As a result, by causing an uneven distribution of force, you can end up damaging the surface framework. 

  • Lack Of Proper Sealing

Most roofs, especially flat roofs, use heat-resistant sealing on the surface. Since the roofs are exposed to direct sunlight all day long, this sealing is extremely important. It prevents damage to the roof by protecting the inner materials and shingles. 

Multiple layers of sealings are usually needed as the sunlight can directly reach every corner of a flat roof. Again, if the sealing material is of poor quality, it can melt the adhesives within the roof layers. 

And that can lead to internal breakage and even cause it to collapse later on. And walking on such cracked surfaces will accelerate the procedure.

  • Use Of Fragile Materials

The use of poor-quality materials and adhesion are the primary reasons behind collapsed roofs. And that doesn’t just stand true for flat roofs but all types of roofs out there. 

People settle for the cheap materials thinking they saved a few bucks but end up destroying the entire roof. And the last time I checked, that’s not very ergonomically sound at all. 

Cheap materials are more prone to breakage as they are less likely to prevent heat and water damage. Furthermore, they don’t have a high-pressure tolerance either. Like the modified bitumen roofs, even normal walking can cause fractures to the framework. 

  • Severe Leaking
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Like heat, water can also end up damaging the internal framework and reduce the impact resistance. The worst thing about water damage is that it literally rots the materials from within and weakens them over time. 

That’s why it’s important to use waterproof materials or at least sealings on a flat roof. Like slanted roofs, flat roofs don’t get to roll the water down in a downward slope. 

Without proper care, this stored water can dampen the surface and leak into the inner layers of a roof. If you walk on such roofs, you’ll apply pressure to the dampened parts and make them distorted. Furthermore, the slippery surface can cause you to fall down as well. 

  • Deformities In Framework

Many people think that the harder the roof surface, the stronger it is. That is a pretty big misconception. For instance – the popularity of BUR roofing is skyrocketing nowadays due to the use of rock and gravel in them. 

People think that they are best (which is indeed true sometimes) because they have such a sturdy framework. But what they fail to realize is that a strong and sturdy roof also needs a sturdy support system. 

So, if your house doesn’t have multiple extra-strong pillars, what’s the point? The heavy roof will continue to suppress down the supporting pillars and end up deforming the pressure points. And the lack of balance will ultimately result in an extremely damaged roof. 


So, does walking on a flat roof damage it? Turns out, with the right pressure and force, it definitely can! 

To prevent that from happening, check the structural integrity of your flat roof every once in a while. And the next time you’re up there to change a tile, make sure to do it as discreetly as possible. Stay on alert at all times and get down immediately at any signs of trouble.