Fibreglass Garage Roof

Fibreglass Garage Roof, Mechanic working on a Car

Using Fibreglass for a Flat Garage Roof

Fibreglass is a material widely used throughout the UK and Ireland as a convenient way to build flat roof garage extensions.

Why Choose Fibreglass?

Fibreglass is often recommended for its non-corrosive, durable nature—making it an ideal roofing solution for the unpredictable weather across the UK and Ireland. Whether it’s hail, rain, snow, or sunshine, a fibreglass flat roof can withstand the elements and provide long-lasting protection. When installed correctly, it can last over 20 years with minimal maintenance.

If you’re unsure about the installation process, our step-by-step installation guide includes practical tips to help you achieve a professional finish.

What Makes Up a Fibreglass Garage Roof?

A fibreglass garage roof typically consists of three essential layers, each working together to create a seamless, watertight finish:

  • OSB3 Board – To begin with, a strong and moisture-resistant base is crucial. While plywood can be used, OSB3 is highly recommended due to its superior durability and resistance to damp conditions.

  • Fibreglass Layer – Next, a fibreglass mat is applied and saturated with resin. As the resin cures, it hardens the material, providing the roof with strength and long-lasting rigidity.

  • Topcoat – Finally, the topcoat is added to seal the roof. This layer not only enhances the appearance with a clean, coloured finish but also protects the surface by providing a tack-free, UV-resistant barrier.

Ideal for All Roof Sizes

A standard double garage in the UK or Ireland is around 12m²—perfectly suited for a fibreglass system. In fact, fibreglass flat roofs work well for both small and large-scale projects, including domestic and commercial buildings.

Finish with GRP Roofing Trims

To give your roof a clean, professional finish, GRP edge trims are essential. Not only do these trims enhance the overall appearance, but they also serve an important functional role. In addition to their decorative value, they help direct water away from the roof and ensure proper drainage, which is crucial for long-term performance.

Before applying the resin and fibreglass mat, you’ll need to install the edge trims. Doing so at this stage helps maintain the seamless finish of your fibreglass garage roof, while also supporting the structure and preventing potential water ingress at the edges.

TRIMS RANGE

Choosing the Right Fibreglass Roofing Kit for Your Garage

Roofing kits are available in two options: Premium and Standard. Both are specifically designed for fibreglass roofing projects, so the best choice depends on the requirements of your fibreglass garage roof.

Premium Roofing Kit

The Premium kit includes a fire-retardant topcoat and is available with either 450g or 600g fibreglass matting. This makes it the ideal option when fire resistance is a priority—for example, if the garage is attached to a home or used to store flammable materials.

It also features a flexible roofing resin, which allows for slight movement due to natural expansion and contraction, offering added durability over time.

Choose:

  • 450g matting for roofs with little to no foot traffic (common in most garages)

  • 600g matting for roofs that may experience moderate foot traffic

Standard Roofing Kit

The Standard kit is a cost-effective solution for standalone garages where increased fire resistance isn’t necessary and no flammable materials are stored. It includes Lloyds Approved Resin and a standard roofing topcoat, making it a reliable choice for simpler installations.

Most Popular Option

Our most popular kit for fibreglass garage roofing is the 15m² roofing kit, which suits the typical size of a double garage in the UK or Ireland.

ROOFING KITS

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