Fibreglass GRP Flat Roofing vs Rubber EPDM Flat Roofing 

Roofing Kits Direct provide flat roofing kits, tools and materials for both Rubber and Fibreglass projects. Therefore we are not biased, our ethic being to provide our clients with choice and the best result. Below are appraisals of the two systems which try not to be influenced by opinion or rumour. We understand that each contractor will have a preference of system. That's good, give us a call.

Fibreglass (GRP) roof inc expansion trim and edging trims

F - Lifecycle - Evident in the UK for 25 - 30 years much more popular in the last 10 years as practices and products have vastly improved

Rubber roofed garden room in woodland backdrop

R - Lifecycle - Evident in the US for 50 years now very popular in the UK

F - Longevity- Guaranteed for 25 years. probably reasonable to expect a little longer although colour may fade over extended time

R - Longevity - Life expectancy 50 years as this system has been around longer. 

F - Certification - NHBC approved  - Fire Retardent

R - Certification - BBA approved - NHBC approved - Fire rated

F - Cost -  Slightly more expensive than EPDM alternative.

R - Cost -  competitive Slightly more cost effective than GRP but more than traditional felt.

F - Suitability - 

  • Green roofs

  • Lightweight 

  • Visually attractive

  • Colour options

  • Strong

  • Jointless under 50 sq.m

  • Complex shape compatible

  • Large roofs require expansion joints

  • No hot flame required.

R - Suitability - ​

  • Green roofs

  • Lightweight

  • Flexible

  • Strong

  • Complex shape requires joins

  • Suits uniformly shaped roofs

  • No hot flame required.

  • Visually standard

F -Damage Resistance - Very high even to vandalism

R - Damage Resistance - Good and durable. Issues with sharps and not impervious to vandalism (Knives etc)

F - Repair profile - Very good, can be almost invisible

R - Repair profile - Very good, but more visible

F - Appearance - first class, easily cleaned

R - Appearance - Good, clean black appearance.

F - Pros

  • Visually

  • Complexity compatible

  • Foot traffic compatible 

  • No joins

  • Resistant to sharps

  • Good repairability profile

  • Not hot flames required

  • Good Longevity

  • Small roofs good for DIY



  • More expensive than EPDM

  • Mandatory to be dry throughout installation

  • Mixing ratios to be considered

  • Large roofs require expansion joints

R - Pros

  • Cost effective

  • Easy to install

  • One piece

  • Can be joined

  • Good repairability profile

  • Not hot flames required

  • Great longevity

  • Good for DIY


  • Complexity means joins

  • Requires additionals for foot traffic

  • Needs to be dry

  • Potential shrikage

  • Susceptible to sharps

We trust the above will help you in your choice - good luck for a successful project