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Stormking Plastics Ltd Variant:
Third party certifications:
  • BBA Agrément Certificate

    BBA Agrément Certificate

    Certificate type

GRP dormers: pre-tiled, light weight and safe.

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+44 (0)1827 311100 www.stormking.co.uk


For use on roofs of domestic buildings with pitches ranging from 25° to 70°.


The Stormking Dormer is an all-in-one solution that cuts costs without compromising quality. Extra specialist engineering goes into each dormer’s inner structural support, so you can rely on a safe and sound product that still boasts a refined profile.

Stormking WARMADORMA© prefabricated dormers consist of a structural timber framing which is supplied either fully-bonded to a preformed fire-retardant GRP outer shell, or as a trussed roof to be tiled on site. The dormers are built around a timber framework and, where specified, a preformed GRP moulded outer shell is added and trimmed prior to finishing. 

Features and benefits:

  • BBA certified for full testing and auditing to ISO standards.
  • All flashings and lead apron incorporated into Stormking dormers.
  • Easy handling and one-lift site installation.
  • No need for independent scaffolding.
  • Properly structured internal framework for solid stability.
  • Anti-cold bridging, fully compliant insulation.
  • Consistently perfect aesthetics, to the last detail.
  • Available in three styles: flat roof lead-effect GRP (incorporating a slight fall towards the outer edge to allow rainwater run-off), trussed pitched roof to be used in conjunction with conventional tiles (available with falls of between 30° and 70°) and pitched roof GRP tiled-effect (available with falls of between 30° and 70°).

General information


Standard colours White and Grey, for further colour options, please contact manufacturer.





Lead effect GRP (glass reinforced plastic) or tile effect GRP.


Timber frame.


All three styles are manufactured in a wide range of size, consult manufacturer.


Two year

From delivery.

Uniclass 2015

Pr_35_90_28_33 Glass fibre-reinforced plastics (GRP) roof componentsPrimary


H40/130 Proprietary GRC components

H40/120 GRC components

Specification data - Glass fibre-reinforced plastics (GRP) roof components Enhanced data

Component type

Flat roof - lead effect GRP.


All three styles are manufactured in a wide range of sizes, consult manufacturer.

Fire performance


External face

Not applicable.

Finish as delivered

Lead effect GRP.

Insulation material

Roof insulation.

Polyurethane insulation.

150 mm thick.

Thermal transmittance: To BS EN ISO 6946: 2007, 0.025 W·m–1K –1.

Wall linings

110 mm polyurethane insulation.

The walls of the dormers are spray-filled internally polyurethane insulation.

Thermal transmittance: 0.026 W·m–1K –1 (BS EN ISO 6946 : 2007).

Roof pitch

Not applicable.

Environmental information

Country of product manufacture

United Kingdom

Digital objects

Platform Compatible Version Certified to



Download now from NBS National BIM Library


Stormking Dormer Product Brochure

Stormking Dormer Product Brochure

Stormking Installation Guide - WARMADORMA© GRP Dormer

Stormking Installation Guide - WARMADORMA© GRP Dormer

Third party certifications

BBA Agrément Certificate

BBA Agrément Certificate

Stormking GRP Prefabricated Roofs, Stormking WARMADORMA - British Board of Agrément Certification

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