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Minerva Contracting Ltd
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GRP Roofing

Just what is GRP?

GRP (Glass Reinforced Polyester) or Fibreglass as it is more commonly known, is a cold applied liquid resin reinforced with glass fibres that cures to form an ultra tough, completely waterproof material.
The technology behind GRP has been in use for decades and provides the ideal platform for waterproofing, particularly flat roofs but also pitched roofs and even vertical elevations. 
Within construction and roofing, a combination of preformed profile sections, glass fibre reinforcement and specially formulated resins are applied to a specially prepared surface (called the 'deck' in the roofing industry) to create a seamless monolithic membrane that is completely waterproof.

What are the benefits of a GRP roofing installation?

Excellent durability

Extremely reliable and hard-wearing, GRP roofing systems are proven to provide decades of effective and durable service. They are the ideal solution for walkways, balconies and terraces with no need for the addition of surface protection such as promenade tiles, however these and other surfaces such as decking can be installed without risk of damaging the GRP.

Complete Flexibility

The incorporation of complex details, changes of direction, steps, gulleys etc is limited only by the skill and imagination of the installer. Bespoke, unconventional details are easily incorporated into a GRP system whilst still maintaining the complete reliability that may otherwise be compromised with traditional systems that require bonded laps and seams.
The choice of colours is endless, and a surface texture can be specified if you wish to provide a non slip surface or simply as an aesthetic preference.
If carried out correctly, alterations and repairs are possible without compromising the integrity of the installation.

Safe and Environmentally Friendly
GRP is applied without flames or heat and negates some of the risks associated with traditional methods.
Compared with many other materials, GRP has a very low environmental impact, taking into consideration not just pollution from manufacture but also the relative longevity of the finished product when properly installed.

Where else can GRP be used?

GRP can be utilitised in almost any situation where you require a waterproof, chemical resistant, long lasting and hardwearing surface. Situations where we have provided a GRP solution include:

  • All types of roofing including flat, pitched, complex box or valley gutters, etc.
  • Balconies, terraces and walkways.
  • Wet rooms and shower rooms, either as a 'tanking' membrane before tiling or as a finished surface.
  • Water tanks, either new installations or in-situ repairs.
  • Swimming pools.
  • Ponds and pond liners, including sheathing of concrete.
  • Lining of vehicles and structures that require frequent harsh cleaning/jet washing such as asbestos vans, refrigerated trucks, etc. 

Can I 'DIY' GRP or apply my existing skills as a roofer?

As a company we have decades of combined experience in the application of GRP waterproofing in countless scenarios, and pride ourselves on our unrivalled expert knowledge of the material and it limitations, whereas many roofing contractors simply consider it another 'string to their bow' with only basic knowledge. Whilst in some straightforward cases this is fine, it can often lead to a compromised laminate especially on larger or more complicated installations.
As GRP roofing becomes more prevalent in mainstream construction, there has been a rise in cheaply available materials, short 'courses' and online training videos.
However without prior experience there are many pitfalls to be avoided that can lead to either a disastrous installation that isn't watertight or a poor quality roof that fails prematurely.
Undoubtedly, traditional roofing skills and knowledge are required to properly incorporate any detailing work into a GRP, but this alone is not enough to ensure a successful installation.

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