Polyroof Products Limited

Protec FW-25

Manufacturer: Polyroof Products Limited 

Materials: Flexible Polyesters 

Protec FW-25 is a liquid-applied, glass-reinforced flexible modified polyester system.

The system consists of:
• Protec FW-25 — a pigmented, flexible modified polyester resin
• Polyroof Powder Catalyst — a 50% Dibenzoyl peroxide powder
• PolyMat 225 — a 225 g·m–2 glass reinforcement
• Uni-Primer DP — a primer for preparing bituminous, wood, concrete, and other substrates, as approved by the Certificate holder
• Twin Pack Metal Epoxy Primer — a two-part primer for preparing metal substrates and other selected substrates as approved by the certificate holder
• Anti-slip Additive — an optional surface finish to provide an anti-slip surface if required

BBA logo

Number: 21/5890
Issue date: 12/12/2023

ETA logo

Number: 24/0067
Issue date: 06/02/2024

Approved for use on

Flat Roofs Green Roofs Inverted Roofs Pitched Roofs Warm Ballasted Roofs Zero Falls Buried Roofs 

For use as a liquid-applied roof waterproofing system on new or existing roofs with limited or pedestrian access in the following specifications:

• exposed warm and cold flat and pitched roofs(1)
• protected warm and cold flat and zero fall roofs (ie covered by pavers or other suitable protection) (1)(2)
• green (extensive) flat, zero fall and pitched roofs(1)(2)
• inverted flat and zero fall roofs(1)(2)

(1) Limited access
(2) Pedestrian access


Concrete Glass Reinforced Polyester Mastic Asphalt Metal Plastic Reinforced Bituminous Membranes Single Ply Membranes - EPDM Single Ply Membranes - PVC Single Ply Membranes - TPO Timber 

The system is suitable for use on the following substrates:
• concrete
• asphalt
• plywood(1)
• OSB 3(2)
• reinforced bitumen membranes (including sanded and mineral surfaced felts)
• insulation (1)
• single-ply membranes(2)
• previously-coated surfaces(2)
• small areas of metal incidental to the roof, eg pipe upstands
• small areas of plastic-coated metal incidental to the roof(1)

(1) Grades approved by the Certificate holder
(2) The advice of the Certificate holder should be consulted on compatibility with the system


25 Years 

The system will achieve an initial life expectancy of at least 25 years. When fully protected, and subjected to normal service conditions in an inverted roof specification with an open covering (eg aggregate pavers), the system can provide an effective barrier to the transmission of liquid water and
water vapour for the design life of the roof in which it is incorporated.

In situations where maintenance or repair of any of the components in the roof structure are necessary (eg protection layer or insulation), the durability of the membrane may be reduced. In these circumstances the Certificate holder should be consulted.

An estimation cannot be given for the life of green roof specifications owing to the nature of use; however, under normal circumstances, it should be significantly greater than for exposed waterproof coverings.

Installation Requirements

The system is only installed by specialist roofing contractors who have been trained and approved by the Certificate holder.

Fire Safety

When tested to DD CEN/TS 1187 : 2012, Test 4 the following systems achieved a classification under BS EN 13501-5 : 2005 of BROOF(t4): • a flat roof system consisting of primed 9 mm thick calcium silicate board, a layer of Uni-Primer DP applied at 0.2 l·m–2, one coat of Protec FW-25 at 0.85 l·m–, a layer of 225 g·m–2 chopped strand glass fibre mat reinforcement and one coat of Protec FW-25 at 0.5 l·m–2

• a flat roof system consisting of a primed 18 mm thick OSB3 board, a layer of polymeric adhesive primer applied at 0.15 ℓ·m–2, a 0.6 mm self-adhesive air and vapour control layer (AVCL), a 150 mm thick tissue faced polyisocyanurate (PIR) insulation board adhesively bonded, layer of polymeric adhesive primer applied at 0.15 ℓ·m–2, a 0.6 mm self-adhesive carrier membrane, one coat of Protec FW-25 at 1 ℓ·m–2, a layer of 225 g·m–2 chopped strand glass fibre mat reinforcement and one coat of Protec FW-25 at 0.5 ℓ·m–2
• a flat roof system consisting of a primed 18 mm thick OSB3 board, a 300 µm polyethylene AVCL, a 150 mm thick aluminium foil faced PIR insulation board mechanically fastened, an 18 mm thick OSB3 board, one coat of Protec FW-25 at 1 ℓ·m–2, a layer of 225 g·m–2 chopped strand glass fibre mat reinforcement and one coat of Protec FW25 at 0.5 ℓ·m–2

In the opinion of the BBA, a roof incorporating the system will be unrestricted under the national Building Regulations in the following circumstances:
• Protected or inverted roof specifications, including an inorganic covering listed in the Annex of Commission Decision 2000/553/EC,
• irrigated green roofs.

The designation of other specifications should be confirmed by reference to the requirements of the documents supporting the national Building Regulations.

The system, when used in pitches of greater than 70°, excluding upstands, should not be used on buildings in England and Wales that have a storey at least 18 m above ground level and in Scotland 11 m above ground level, and which contain: one or more dwellings, an institution, a room for residential purposes (excluding any room in a hostel, hotel or boarding house), student accommodation, care homes, sheltered housing, hospitals or dormitories in boarding schools.

If allowed to dry, the plants used may allow flame-spread across the roof. This must be taken into account when selecting suitable plants, and appropriate planting, irrigation and/or protection should be applied to ensure that the overall fire-rating of the roof is not compromised.

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Polyroof Product Ltd

Furness House
Castle Park Industrial Estate
Flintshire CH6 5XA

T : 01352 735135

E : info@polyroof.co.uk

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