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GRP Mushroom Roof Vent – 75mm
GRP Mushroom Roof Vent – 75mm
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Moisture Relief & Supplementary Ventilation for GRP Flat Roofs
This GRP Mushroom Roof Vent (75mm) is designed to provide controlled vertical ventilation through a fibreglass flat roof system.
Commonly installed in refurbishment and overlay projects, it helps relieve trapped moisture vapour and reduce pressure build-up within the roof structure.
Suitable for use with most GRP flat roofing systems.
What It’s Used For ▸
- Releasing trapped moisture in existing roof decks
- Supporting ventilation in cold roof constructions
- Reducing risk of vapour pressure build-up in overlay systems
Often installed where full strip-out of the existing roof is not being undertaken.
Why It Matters ▸
Trapped moisture beneath a new GRP membrane can lead to pressure build-up and blistering over time. A mushroom vent provides a controlled outlet for vapour, helping stabilise the roof structure.
It provides vertical ventilation only and is not a substitute for designed cross flow ventilation where required by building regulations.
Installation Overview ▸
- Core drill the deck to suit the vent stem.
- Position the vent so the stem aligns with the hole and the flange sits flat on the surface.
- Mechanically fix the flange if required.
- Laminate the flange into the GRP base coat using CSM reinforcement.
- Consolidate thoroughly and apply top coat as part of the system.
Ensure roof falls direct water away from the vent base.
Technical Specification ▸
- Diameter: 75mm
- Type: Mushroom-style roof vent
- Colour: Grey
- Application: GRP roofing systems
Summary ▸
The GRP Mushroom Roof Vent (75mm) provides controlled vapour release within fibreglass roofing systems, helping manage moisture in refurbishment and overlay applications.
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