RESTRIM Flat Sheet F300 — 300 mm Flat Flashing Trim (20 m & 3 m)

The RESTRIM Flat Sheet F300 is a pre-formed GRP (glass reinforced plastic) flashing sheet designed for continuous, seamless transitions where a pitched roof meets a flat roof or in other interface zones. Offered in two packaging options — a full 20 m roll or a 3 m cut length — it provides flexibility and ease of installation to suit varying project scales.

Key Features & Benefits

• Precision-engineered GRP: Manufactured with the same robust material standard as the rest of the RESTRIM / RES TRIMS family, ensuring durability, UV stability, and weather resistance.
• Flexible yet stable: Allows for minor surface irregularities and alignment during installation while maintaining dimensional integrity under load.
• Seamless flashing continuity: Used as continuous flashing beneath slate or tile abutments, the F300 helps prevent water ingress at critical junctions.
• Gutter-lining capability: Can also serve as internal lining for box gutters or similar details, offering dual-purpose utility.
• Easy jointing and finishing: Overlap joints (typically 50 mm) can be bandaged and resin-sealed to preserve continuity and structural integrity.

Multiple length options:

• 20 m roll: allows long continuous runs with minimal joints ?
• 3 m length: ideal for smaller details, stock management or site cut backs

Compatibility: Fully compatible with RESTRIM / RES TRIMS accessory trims, adhesives, and GRP roofing systems.

Check out our full range of roofing supplies.

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At JJ Building Materials, we're committed to supplying quality building products at competitive prices, backed by the service and expertise you'd expect from an established independent merchant. Whether you're a trade professional managing large-scale projects or a homeowner taking on a DIY renovation, we're here to help you find the right products for the job.

As part of the JJ Roofing Supplies Group, we build on decades of experience supplying construction materials across the UK. We've expanded beyond roofing to offer a growing range of building materials, including timber, insulation, landscaping products, plumbing supplies, flooring, doors, bricks, fencing, garden buildings and much more – all available to order online with nationwide delivery.

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• Competitive prices on leading brands and quality products.
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Every order is personally reviewed by our experienced team to ensure everything is correct before dispatch. We offer delivery from as little as the next working day on selected products, so please refer to the dark blue Estimated Delivery box above for the expected delivery timeframe for this item.

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