Polyroof’s 185 system is the UK’s leading GRP roofing system and has become synonymous with premium performance. Polyroof 185 was the first ever fibreglass system to receive BBA certification and has been installed on roofs and balconies continuously since 1984. Always applied to a Polyroof approved OSB3 or plywood deck, the system carries a 30 year durability rating and provides an exceptionally tough and hardwearing membrane.
grp roof

Extra-Tough and Hardwearing GRP Roofing System


  • The 185 system is always applied to Polyroof approved plywood or OSB3 boards.
  • Refurbishments: Usually used on roofs involving strip-and-replace works.
  • New Build: Ideal for any new build timber roof applications.
  • Roof Designs: Ideal for use as part of a warm or cold deck roof design.
  • Balconies & Walkways: Available with a BBA approved extra tough anti-slip finish for trafficked areas.


  • Ideal for small to medium sized projects requiring an extra tough, durable and highly impact-resistant finish.
  • Extremely hardwearing and can withstand regular foot traffic without additional protection
  • Available in a wide range of colours and finishes.
  • Fire performance: Classified as BROOF(t4), the top rating achievable for a flat roof system and designating Polyroof 185 as unrestricted under UK the national Requirements (see Section 7 of BBA Certificate 91/2604).
  • BBA durability rating of up to 30 years.
  • Carries Polyroof’s trusted Accredited System Guarantee.
  • The guarantee is supported for 20 years by an independently administered trust fund with additional annually renewable insurance as standard.
  • Standard colours are Dark Battleship Grey, Light Battleship Grey, Lead Green, Dark Grey and Havana Brown (see our Colours & Finishes page for more options and further details)
Polyroof 185 System Brochurepolyroof 185 specification Download
Guarantee & Quality Assurancepolyroof 185 guarantee Download
BBA Certificate (91/2604)polyroof 185 bba certificate Download

Polyroof Outline Specifications

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Polyroof GRP Drip Trim

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Polyroof GRP Upstand Trim

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Ventilated Perimeter

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Nautica, Hampshire

This attractive new apartment block development on the south coast of England required a thermally efficient roof design that could also incorporate photovoltaic (PV) cells. Due to the strong winds the roof was subjected to, the client required the PV cells to be mechanically fixed into the roof structure. Having worked with Polyroof on various new build developments in the past, a solution was sought that could meet all of the environmental and energy demands whilst also providing durable and fully guaranteed waterproofing…
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Explorer Court, Plymouth

The project included the waterproofing of over 400 square metres on the main barrel roof and lower penthouse balconies for a highly successful and NRFC award winning development by Barratt Homes. The main roof was designed with a wave effect, with an internal radius of 5672mm. For the balcony areas, the designer specified decorative timber decking over the waterproof membrane, which meant that the membrane had to be durable enough to bear the weight from the decking… [Read More]


Flush-Fitted Skylight for Orangery Roof

The Polyroof 185 system was specified as it provided the client with a seamless and durable waterproofing solution that would look stylish and modern, and could be incorporated with the rest of the building’s design. A key feature to the design of the roof was a large glass skylight that the architect designed to be level with the surrounding roof, creating a visually striking and modern look to the roof. However this presented a challenge as an upstand to the rooflight was still required to ensure a fully weatherproof detail could be formed… [Read More]


Domestic Balcony Projects

The Polyroof 185 system has been specified on numerous balcony and walkway areas across the country. Carrying an insurance-backed guarantee for 20 years, the system provides a BBA approved anti-slip finish that is extremely tough and long lasting. As is often the case, the cost effectiveness and the aesthetics of the balcony are of upmost important to the client. This modern balcony design was incorporate a coloured finish as chosen by the client and an attractive glass balustrade around the perimeters… [Read More]


Spiral Roof for Woodland Trust

As described by the Woodland Trust, Glen Finglas is a great expanse of ancient woodland, lochs and open heathland, sitting at the heart of Loch Lomond and The Trossachs National Park and home to one of the best examples of upland wood pasture in Scotland. The newly constructed Gateway Building was designed to blend in with the surrounding woodlands and featured a circular timber-clad exterior with a spiraling, curved roof. The Woodland Trust chose Polyroof to provide a guaranteed waterproofing solution that would complement the aesthetics of the building… [Read More]

185 System Application Video

This video produced in conjunction with the LRWA demonstrates an application of flexible and resistant polyesters using Polyroof’s 185 System.