EPDM vs TPU Waterproofing: What You Should Know?

Written By Adam Paul - Waterproofing Expert

EPDM waterproofing and TPU waterproofing are two types of most used waterproofing membranes, which are used to protect buildings from water and moisture penetration. In order to choose the right type of the waterproofing membrane, you should know the differences between them before you apply.

So as waterproofing experts, Aqviz, we prepared a complete comparison guide by considering the EPDM vs TPU waterproofing. We have included main differences in material composition, water resistance, breathability, flexibility, chemical resistance, and UV resistance. As minor differences, we included adhesion, tear resistance, seam integrity, root penetration resistance, eco-friendliness, fire resistance, anti-slip resistance, toxicity and self-expanding capability.

Material Properties Comparisons Between EPDM and TPU Waterproofing

These are the material composition, performance, durability, and environmental resistance comparisons between EPDM and TPU waterproofing.

EPDM (Ethylene Propylene Diene Monomer) waterproofing membranes are made from synthetic rubber membrane, while TPU (Thermoplastic Polyurethane) is a blend of urethane polymers.
Both EPDM and TPU membranes offer strong water resistance
EPDM waterproofing has a very low breathability, while TPU waterproofing has a moderate breathability
EPDM waterproofing is more flexible than TPU waterproofing
EPDM waterproofing has a lower chemical resistance than TPU waterproofing
EPDM waterproofing has a higher thermal stability than TPU waterproofing
EPDM has a higher UV resistance than TPU waterproofing

Composition Difference Between EPDM and TPU Waterproofing

EPDM (Ethylene Propylene Diene Monomer) waterproofing membranes are made from synthetic rubber membrane, while TPU (Thermoplastic Polyurethane) is a blend of urethane polymers.

EPDM (Ethylene Propylene Diene Monomer) waterproofing is a synthetic rubber membrane that is made from ethylene and propylene. EPDM waterproofing membranes have an excellent elasticity and UV resistance. It is highly flexible and can stretch without cracking, making it ideal for various roofing and waterproofing applications.

TPU waterproofing membranes are thermoplastic polyurethane-based material. TPU waterproofing membranes consist of hard and soft segments chemically bonded together. It helps to increase tensile strength, better abrasion resistance, and enhanced toughness. Due to their thermoplastic nature, TPU waterproofing membranes can be welded. Hence it can join more tightly than EPDM.

Water Resistance Difference Between EPDM and TPU Waterproofing

Both EPDM and TPU membranes offer strong water resistance

EPDM waterproofing provides outstanding water resistance due to its seamless application and high elasticity. EPDM waterproofing prevents cracks that could lead to water infiltration to the substrate. It resists ponding water, making it a popular choice for low-slope roofs.

But TPU waterproofing membranes are not completely waterproof due to their weldable seams. If there is any loose in the seam, water can leak to the substrate and can cause many water related problems to the structure over time. So it is highly recommended that precise seam-welding techniques be used when installing TPU waterproofing membranes.

Breathability Differences Between EPDM and TPU Waterproofing

EPDM waterproofing has a very low breathability, while TPU waterproofing has a moderate breathability

EPDM has a very low breathability compared to the TPU waterproofing membranes. Hence, EPDM tends to create a vapor barrier on the substrate, considering the TPU membranes. Therefore EPDM can be used to block completely vapor on surfaces such as flat roofs and slabs.

TPU waterproofing membranes have a moderate breathability due to their semi-permeable polyurethane composition. It allows moisture vapor transmission through the layer. This characteristic helps minimize condensation and mold growth beneath surfaces, ideal for decks or balconies.

Flexibility Difference Between EPDM and TPU Waterproofing

EPDM waterproofing is more flexible than TPU waterproofing

EPDM waterproofing offers superior flexibility due to its synthetic rubber composition. EPDM waterproofing can stretch up to 300% without tearing. This elasticity makes it ideal for structures that experience movement, expansion, or contraction. EPDM waterproofing performs well in extreme weather conditions, adapting to substrate shifts without cracking it.

TPU waterproofing also has a good flexibility, but it’s slightly more rigid because of its thermoplastic nature. TPU waterproofing is better suited for environments demanding durability under moderate movement, such as balconies or terraces, rather than high flexibilities and movements.

Chemical Resistance Difference Between EPDM and TPU Waterproofing

EPDM waterproofing has a lower chemical resistance than TPU waterproofing

EPDM is resistant to acids, alkalis, and ozone. Therefore EPDM can be used for outdoor usages such as roofs, and slabs. But when it is prone to petroleum-based solvents, it can be degraded over time.

But TPU waterproofing membranes consist of a polyurethane based composition. Hence it can withstand acids, alkalis, ozone as well as oils, solvents, and industrial chemicals. Hence TPU is applied for garages and industrial floors where chemical exposure occurs frequently.

Temperature Stability Difference Between EPDM and TPU Waterproofing

EPDM waterproofing has a higher thermal stability than TPU waterproofing

EPDM membranes have excellent temperature stability. EPDM waterproofing temperature withstand from -50°C (-58°F) to 150°C (302°F). Hence EPDM waterproofing is ideal for climates experiencing extreme temperature fluctuations. In our experience at Aqviz, EPDM has consistently performed well on roofs exposed to intense sunlight and freezing winters.

TPU waterproofing membranes offer moderate temperature stability, typically from -40°C (-40°F) to 100°C (212°F). TPU waterproofing can deform under sustained extreme heat. Hence it is not able to use on harsh conditioned environments.

UV Resistance Difference Between EPDM and TPU Waterproofing

EPDM has a higher UV resistance than TPU waterproofing

EPDM has excellent UV resistance due to its rubber-based composition and carbon black content, which helps absorb and dissipate UV radiation. This makes it highly durable in prolonged sun exposure, preventing cracking, fading, or degradation over time. EPDM membranes can last over 50 years with minimal UV-related damage.

TPU waterproofing membranes have moderate UV stability. TPU waterproofing can degrade under prolonged UV exposure without additional protective coatings or stabilizers. Therefore, Aqviz we, recommends EPDM waterproofing for external applications with constant sunlight exposure over time.

Read our similar expert guide related to EPDM and TPU waterproofing

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PVC vs TPU waterproofing

Functional and Environmental Impact Comparisons Between

These are the mechanical strength, safety, environmental impact, and usability comparisons between EPDM and TPU waterproofing

Properties	EPDM	TPU
Adhesion	Requires adhesives for bonding, moderate adhesion strength.	Naturally high adhesion to various surfaces, reducing the need for additional adhesives.
Tear Resistance	Good tear resistance but can puncture under sharp objects.	Superior tear resistance due to its high tensile strength.
Seam Integrity	Requires seam adhesives or tapes, potential weak points in seams.	Heat-weldable seams create a stronger, seamless finish.
Root Penetration Capability	Moderate resistance, can be compromised over time.	High resistance to root penetration, ideal for green roofing applications.
Eco-Friendliness	Recyclable but contains synthetic rubber, making disposal challenging.	More eco-friendly, often recyclable with lower environmental impact.
Fire Resistance	Poor fire resistance, requires additional fire-retardant coatings.	Better fire resistance due to polyurethane properties.
Anti-Slip Resistance	Smooth surface, can become slippery when wet.	Naturally higher slip resistance due to its textured formulation.
Toxicity	Low toxicity, but may release minor VOCs over time.	Generally non-toxic and safer for human contact.
Self-Expanding Capability	No self-expansion, remains in its installed state.	Some formulations can expand slightly, adapting to surface changes.