Acrylic vs. EPOXY Waterproofing: What Are the Differences?

Written By Adam Paul - Waterproofing Expert

Acrylic waterproofing and EPOXY 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 acrylic vs EPOXY waterproofing. We have included main differences in material composition, water resistance, breathability, flexibility, chemical resistance, temperature stability, 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 Acrylic and Epoxy Waterproofing

These are the material composition, performance, durability, and environmental resistance comparisons of Acrylic and EPOXY waterproofing

Acrylic waterproofing is a water-based, polymer-modified coating that is made from acrylic resins, while EPOXY is a two-component system consisting of epoxy resin and a hardener
Acrylic waterproofing has a lower water resistance than EPOXY waterproofing
Acrylic waterproofing is more breathable than Epoxy waterproofing
Acrylic waterproofing is more flexible than EPOXY waterproofing
Acrylic waterproofing has a lower chemical resistance than EPOXY waterproofing
Acrylic waterproofing has a lower thermal stability than EPOXY waterproofing
Acrylic waterproofing has a higher UV resistance than EPOXY waterproofing

Composition Difference Between Acrylic and Epoxy Waterproofing

Acrylic waterproofing is a water-based, polymer-modified coating that is made from acrylic resins, while EPOXY is a two-component system consisting of epoxy resin and a hardener.

Acrylic waterproofing is a water-based, polymer-modified coating that is made from acrylic resins. Acrylic waterproofing consists of compounds such as acrylic polymer, water, fillers, pigments, additives, and preservatives. Acrylic forms a highly water resistant, UV resistant, flexible protection layer on the substrate after it is applied on. Acrylic waterproofing is an environmentally friendly coating with low VOC.

EPOXY waterproofing consists of epoxy resin and hardener. Once they mixed together to a recommended proportion, it forms a solid compound. When the epoxy compound cures, it forms a solid, non-porous layer that helps to prevent water leaking through the layer. Epoxy waterproofing is a highly water-resistant, less flexible, higher tensile strength, and highly effective for positive and negative water pressures.

Water Resistance Difference Between Acrylic and Epoxy Waterproofing

Acrylic waterproofing has a lower water resistance than EPOXY waterproofing

Acrylic has a moderate water resistance compared to epoxy waterproofing. Acrylic waterproofing layer is more permeable than epoxy. Hence, it is prone to degradation due to constant water exposure. Its resistance is sufficient for surfaces with minimal water accumulation, but prolonged moisture can lead to wear over time. To prevent tis and improve the longevity, multiple acrylic coatings should be applied on the surface.

Epoxy membranes offer superior water resistance due to their less flexibility and higher tensile strength. Epoxy waterproofing effectively handles both positive and negative side water pressures.

Breathability Differences Between Acrylic and EPOXY Waterproofing

Acrylic waterproofing is more breathable than Epoxy waterproofing.

Acrylic waterproofing is highly breathable. Acrylic waterproofing allows to escape the trapped moisture from the substrate. Higher breathability of the acrylic waterproofing reduces the risk of blistering and peeling the waterproofing membrane, and making it suitable for areas prone to dampness

Epoxy waterproofing membranes are not breathable due to their seamless, non-porous resin composition. Therefore, epoxy waterproofing is ideal for industrial areas and chemical storage areas. Due to the less breathability, moisture can be trapped on the surface. This causes to blistering of the layer and prolonged water-related problems over time.

Flexibility Difference Between Acrylic and EPOXY Waterproofing

Acrylic waterproofing is more flexible than EPOXY waterproofing

Acrylic waterproofing is highly flexible due to its elastomeric nature, allowing it to expand and contract with structural movements. Acrylic waterproofing’s elasticity depends on the thickness and reinforcement used for the mixture. Hence, acrylic waterproofing has a limited stretch range and should not be used in high-movement areas.

Standard EPOXY waterproofing is not flexible. But some improved epoxy waterproofing can be flexible due to polymer resin compositions. We highly recommend you to use a limited flexible epoxy for the minor movable structure in order to protect the substrate properly.

Chemical Resistance Difference Between Acrylic and EPOXY Waterproofing

Acrylic waterproofing has a lower chemical resistance than EPOXY waterproofing

Acrylic waterproofing has moderate chemical resistance. Hence it is suitable for general outdoor and residential applications. Acrylic waterproofing can withstand mild acids, alkalis, and UV exposure, but prolonged exposure to harsh chemicals or industrial pollutants can degrade its performance over time.

Epoxy waterproofing membranes, however, possess superior chemical resistance due to their robust, resin-based formulation. EPOXY waterproofing withstands exposure to harsh chemicals, solvents, and acids effectively. Therefore, epoxy waterproofing is highly recommended for industrial facilities, laboratories, garages, and chemical storage areas.

Temperature Stability Difference Between Acrylic and EPOXY Waterproofing

Acrylic waterproofing has a lower thermal stability than EPOXY waterproofing

Acrylic waterproofing has a lower temperature stability than the EPOXY waterproofing. It has a narrow range, hence it can soften under extreme heat or become brittle in freezing conditions. Hence acrylic waterproofing is suitable for temperate climates but may require additional protection in areas with severe temperature fluctuations to protect the layer from extreme temperatures.

Epoxy waterproofing membranes have an excellent temperature stability. It can withstand a wide range of temperature variations. Hence it is suitable for both high-temperature areas and outdoor applications exposed to severe climatic changes, such as rooftops and terraces.

UV Resistance Difference Between Acrylic and EPOXY Waterproofing

Acrylic waterproofing has a higher UV resistance than EPOXY waterproofing

Acrylic waterproofing has excellent UV resistance, making it ideal for outdoor applications like roofs, facades, and terraces. Its formulation includes UV-stable polymers that prevent degradation, discoloration, and brittleness when exposed to prolonged sunlight.

Epoxy waterproofing membranes generally offer a lower UV resistance. Epoxy waterproofing layer can deteriorate under prolonged sun exposure, leading to discoloration, chalking, and reduced effectiveness due to UV rays. To enhance UV stability of the EPOXY waterproofing, the top coat should be applied.

Read our similar expert guide related to acrylic and epoxy waterproofing

Functional and Environmental Impact Comparisons Between Acrylic and EPOXY Waterproofing

These are the mechanical strength, safety, environmental impact, and usability comparisons between Acrylic waterproofing and epoxy waterproofing.

Properties	Epoxy Waterproofing	Acrylic Waterproofing
Adhesion	Strong adhesion to concrete, metal, and tiles	Good adhesion but may require a primer on some surfaces
Tear resistance	High tear resistance due to rigid structure	Moderate tear resistance but flexible against cracks
Seam integrity	Seamless application, forms a monolithic layer	May have weak points at overlaps or joints
Root penetration capability	Low resistance to root penetration	Better resistance, often used in green roofs
Eco-friendliness	Contains solvents, less environmentally friendly	Water-based and eco-friendly with low VOCs
Fire resistance	High fire resistance, does not catch fire easily	Moderate resistance, may require fire-retardant additives
Anti-slip resistance	Smooth surface, may need an additive for slip resistance	Naturally textured, offering better slip resistance
Toxicity	Can release harmful fumes during curing	Non-toxic and safer for residential use
Self-expanding capability	No self-expansion, remains rigid	Expands and contracts with surface movements