Properties of Liquid Rubber EPDM & Technical Information

There’s only one genuine EPDM Liquid Rubber and its ours. Imagine a durable, easily applied liquid version of traditional single-ply EPDM membrane. This is proven sealing and coating technology that’s been in use for decades. Now it’s available for your projects. 

The science of EPDM gives it two unique properties that no other rubber product offers. Firstly, UV-light and and ozone don’t affect it. Secondly, our genuine Liquid Rubber can handle continuous exposure to temperatures above 150° F (302 °C). Because of the resulting flexibility, this is just one of the properties that gives genuine Liquid Rubber the best ageing properties of all the elastomers. 

Learn about the following on our How to Apply Liquid Rubber page: 

  • Liquid Rubber coverage
  • Preparing surfaces for application
  • How to mix Liquid Rubber
  • Curing 


Volume Solids: 63.5% 

Spreading Rate: A 0.5 mm (0.02 in.)dry film will result when liquid is applied at the rate of 46 ft2 per gallon on a smooth surface.

A rate of 3.7–3.0 m2 (40–42 sq. ft) per gallon allows for average surface roughness.

Theoretical Coverage: 95 m2 (1020 ft2) per gallon at
0.025 mm (0.001 in.) dry. 

Weight per US gallon: 3.63 kg (8 lb) when mixed 

Elongation: 180–200% 

Brittle Point: -52 °C (-62 °F) 

Permeability: 0.1 perm

Weatherometer  2000 hours (ASTM D4459-8-03)

Peel Adhesion: 14.8 N/m (4.85 lb/linear inch) on Firestone EPDM.

Pot Life: 4–10 hours depending on temperature.

Cure rate at 70° F: 7–8 hours to touch
24–30 hours to walk on
5–7 days full cure 

Thinning – to thin Liquid Rubber, you can use most aliphatic and aromatic hydrocarbon solvents including the following: 

  • Mineral spirits
  • VM&P Naphtha
  • Xylol. 

IMPORTANT: to minimise distortion, always use weaker solvents when coating EPDM rubber sheet.

Chemical Resistance – Cured EPDM rubber resists acids, alkalis and polar solvents (alcohols, ketones and glycols). However, you should avoid getting oils and fats into contact with the Liquid Rubber because these substances will soften it. 

The information presented herein is furnished free of charge and is based on technical data that we believe to be reliable. It is intended for use by persons having technical skill and is at their own discretion and risk. Since conditions of use are outside our control we make no warranties, express or implied, and assume no liability in connection with any use of this information. Nothing herein is to be taken as a license to operate or a recommendation to infringe any patents.