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What is GRP Fibreglass Roofing?

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What is GRP Fibreglass Roofing?

GRP fibreglass roofing is one of the most reliable and durable flat roofing systems on the market today. Widely used throughout residential, commercial and industrial properties, it offers a seamless, waterproof finish that can withstand harsh weather conditions, all while requiring very little maintenance. No matter if you’re having a bay window installed, a new extension built or require an existing, ageing flat roof to be replaced, here’s everything you need to know about GRP fibreglass roofing, including its benefits. 

What does GRP stand for?

GRP stands for Glass Reinforced Plastic. It’s essentially a composite material that’s made by combining polyester resin with layers of glass fibre matting. Once cured, the material will form an exceptionally strong, rigid and waterproof surface. GRP fibreglass roofing has been used for many decades in different industries where durability is essential, such as:

  • Marine boat construction
  • Arespace engineering
  • Automotive manufacturing
  • Chemical storage tanks
  • Architectural structures

How does GRP fibreglass roofing work?

A GRP fibreglass roof is constructed by applying multiple layers of materials that work together to create a sealed and waterproof membrane. This protects the integrity of the building and the rest of the roof line, such as the rafters, boarding and insulation. GRP fibreglass roofing is installed in a different way when compared to other roofing materials. Here’s what the installation process involves:

  1. The roof deck is prepared, ensuring it’s clean, dry and made from OSB3 boarding
  2. A resin coat is applied across the entire surface
  3. Chopped strand glass fibre matting is embedded into the wet resin
  4. Additional resin is applied to fully saturate the matting
  5. The roof is allowed to cure as one solid structure
  6. It’s finished with a coloured topcoat to protect the material against UV rays and weathering

What are the benefits of GRP fibreglass roofing?

There are multiple reasons as to why someone would choose GRP fibreglass roofing over other roofing materials. From its remarkable durability and exceptional waterproof properties to its long-lasting integrity and low maintenance, here are just some of the benefits associated with it:

Exceptional durability

One of the biggest advantages of GRP fibreglass roofing is its strength and durability. Once cured, the roof becomes highly resistant to cracking, everyday wear and tear and general impact. If it’s installed professionally by a competent expert, such as us here at Amber Flat Roofing, then the roof can last anywhere between 30-50 years, with the right maintenance. 

Impressive waterproof properties

GRP fibreglass roofing is completely seamless. There aren’t any overlaps or joints in the GRP fibreglass roofing materials that can fail over the course of time. As a result, this greatly reduces the risk of leaks when compared to traditional roofing systems, making GRP fibreglass roofing a great option for durable, waterproof roof materials when compared to others on the market. 

Low maintenance

GRP fibreglass roofs will require very little ongoing maintenance. This is one of the reasons why it’s such a popular roofing material for both domestic and commercial clients alike. In addition, there’s no need for regular re-coating or replacing loose sections because GRP fibreglass roofing really is that durable. Typically, when it comes to making sure that GRP fibreglass roofing is looking its best, you’ll need to:

  • Remove leaves and debris
  • Keep outlets clear
  • Occasionally wash the surface
  • Inspect the flashings once a year

Modern & sleek finish

GRP fibreglass roofing provides a smooth and clean appearance that complements both modern and traditional properties. The great thing about GRP fibreglass roofing is that you can choose the colour of the topcoat. 

You’ll have a choice between grey, dark grey, black, green and white. Not only does the topcoat enhance the colour and overall look of the roof, but it also includes a non-slip texture, which is great if it’s used for certain applications, like walkways or balconies. 

UV resistant

Unlike other types of roofing material, GRP fibreglass roofing is protected with an additional UV-resistant topcoat. This helps to prevent the material from fading, cracking and experiencing surface deterioration. As such, the lifespan of the roof is elongated, and repairs and replacements will be extremely infrequent, if at all.

Strong yet lightweight

Despite its impressive strength, GRP is relatively lightweight. Not only does this mean that any structure with fibreglass roofing will not experience or have to withstand excessive loads, but it also makes it a highly versatile material. As such, roofing professionals, such as us here at Amber Flat Roofing, are able to use it on:

  • Extensions
  • Bay windows
  • Dormer windows
  • Garden rooms
  • Outdoor offices
  • Porches
  • Balconies 
  • Garages

Excellent weather resistance

GRP fibreglass roofing performs well and is able to withstand a wide range of different weather conditions, including frost, snow, ice, high winds, extreme heat and heavy rain. This is thanks to its rigid structure. In turn, this ensures maximum integrity throughout the changing weather conditions, no matter how extreme.

Applications: when is GRP fibreglass roofing used?

You might think that GRP fibreglass as a roofing material is expensive and only used by commercial clients to make a premises look modern and sleek. But you’d be mistaken. GRP fibreglass can be used for domestic applications as well as commercial. 

Its use isn’t limited to large, sleek and modern-looking buildings. In fact, you can use GRP fibreglass roofing for a wide range of different applications, both at home and in the workplace. Those applications include, but are not limited to, the following:

  • House extensions
  • Garages
  • Bay windows
  • Dormer windows
  • Porches
  • Balconies
  • Roof terraces
  • Garden offices
  • Commercial buildings
  • Schools
  • Apartment blocks 
  • Roof valleys
  • Gutters
  • Bespoke waterproof detailing

How long does GRP fibreglass roofing last?

When installed properly, GRP fibreglass roofing can last anywhere between 30-50 years. Here at Amber Flat Roofing, we understand how important the initial roof installation is in terms of elongating its lifespan as much as possible. 

That’s why we’ll only ever use the best materials and draw upon our expert workmanship to ensure the flat roof installation using GRP fibreglass is executed seamlessly. There are a number of different things that will affect the lifespan of a GRP fibreglass roof, including:

  • Installation quality
  • Roof design
  • Exposure to weather
  • Maintenance
  • Quality of materials used 

GRP fibreglass roofing vs felt roofing: which is better?

It can be tough to decide which material would be better for your flat roof. But the good thing is that both felt and GRP fibreglass materials can be used for flat roof installations. However, there are some differences between the two that you should be made aware of. This includes:

  • Lifespan – where felt lasts between 10-20 years, GRP fibreglass roofing lasts around 30-50 years. However, GRP fibreglass roofing is more costly, so that needs to be a part of the decision you make also
  • Seams – GRP fibreglass roofing will often not leave any seams once the job is complete. Felt, on the other hand, will present a few joints, but nothing noticeable
  • Waterproof properties – both GRP fibreglass roofing and felt roofing materials are waterproof and weather resistant
  • Maintenance – neither felt nor GRP fibreglass roofing will need constant maintenance, especially not within the first decade or two
  • Appearance – both felt and GRP fibreglass roofing materials look modern and sleek, and so the material you choose will largely be down to personal preference
  • Crack resistance – GRP fibreglass roofing and felt roofing materials are crack-resistant until they begin to age

Amber Flat Roofing is able to carry out roof installations near you using a wide range of materials, including rubber, fibreglass and felt. If you’re in need of a roof installation service or require roof repairs, then get in touch with a member of our friendly, knowledgeable and experienced team today – we’re always happy to hear from you.

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