Frequently asked questions

 GRP stands for Glass Reinforced Plastic, also commonly known as fibreglass. It is a versatile material used extensively in construction and manufacturing for its strength, durability, and lightweight properties. GRP is popular in applications such as roofing, terraces, walkways, balconies, and fishponds due to its excellent waterproofing capabilities and resilience against weathering.  

Using GRP (Glass Reinforced Plastic), commonly known as fibreglass, for your flat roof covering offers several compelling advantages:

1. Durability: GRP roofs are highly durable and have a long lifespan, typically lasting 30 years or more with proper maintenance.
2. Waterproofing: GRP provides a seamless and completely waterproof membrane when applied correctly, ensuring protection against leaks and water ingress.
3. Strength: It offers excellent structural strength while remaining lightweight, making it suitable for various roof designs without compromising on performance.
4. Versatility: GRP can be applied to various substrates including asphalt, concrete, felt, and existing GRP surfaces, making it versatile for different roof types and refurbishments.
5. Low Maintenance: Once installed, GRP roofs require minimal maintenance. They are resistant to UV degradation, corrosion, and general wear and tear.
6. Aesthetic Appeal: GRP roofs can be finished in a range of colors and textures, offering flexibility in design to complement any architectural style.
7. Environmental Benefits: GRP is environmentally friendly as it is 100% recyclable and has a low environmental impact during manufacturing and installation.

In summary, choosing GRP (fibreglass) for your flat roof provides a cost-effective, durable, and reliable solution that requires little maintenance and offers long-term protection for your property

GRP has to be installed on a new roof deck, this is normally made from 18mm OSB3 boards. We then install the outside trims to the deck using 20mm staples an bandage all joints and trims. Once that is complete we then begin to lay the GRP to the roof deck. This is done by applying a layer of resin to the deck, rolling out the 450csm (fibreglass matting) and again applying more resin to bond everything together creating a continuous joint free membrane. Once the roof is completely dry we sand the GRP ready for the top coat of your choice. 

If the roof or balcony is to be walked on, instead of using 450csm we would use the more durable 600csm which will incorporate slate granules in the top coat giving it a great anti slip coating come rain ice or snow. 

Please take a look at some of our roof terraces or balconies in our gallery.  We are sure you will be pleased with the outcome just like our clients are. 

Unfortunately that is a hard question to answer as it comes down to a number of factors, including the contractors used.  We are however confident that if it is done correctly it will out perform any other flat roofing material on the market.

A warm roof is where the insulation is installed above the rafters.  A warm roof build up will consist of a 11-18mm subdeck on top of the rafters, followed by a vapour control layer, followed by the required thickness of rigid insulation (normally 120-130mm), with a layer of OSB3 tongue and groove boards finished with the fibreglass membrane. 

This way the roof is thermally efficient as it retains the heat from the room below and its also accepted to be the ideal option in the UK with its climate.  

A cold roof construction is where the insulation is laid between the rafters and has at least a 50mm gap to allow vented airflow between the roof deck and ceiling void, meaning warm air will be exhausted. Without the ventilation then condensation would build up and rot the roof from the inside out. These roofs are less thermal efficient.

OUR OPINOIN, if you can have a warm roof, then we would recommend that option.

There are many different factors that are taken into consideration when quoting for a new flat roof.  These include size, roof construction, access, if the roof is to be used as a terrace, flat roof windows and more.  For this reason we would have to come and take a visit and get an understanding of what you are expecting so we can deliver the outcome you are after. 

YES, Fibreglass is one of the toughest materials for roof terraces, balconies or even outdoor steps.  If you intend on using it in this way it is important that we use a 600g matting (minimum) finished with an anti-slip coating.  However, if access is only required for window cleaning then a normal 450g matting would be suitable.

The answer to this is NO.  Although the summer months are better due to dry weather, fibreglass roofs can be laid all year round providing there is shelter from the elements.  Fibreglass cannot get wet during installation and neither can the OSB3 roof deck.  Ideally even during the hottest days a shelter is best as this makes sure the resin does not set too quickly.

Although professionals make Fibreglassing look easy it is not advised to try it yourself.  If done incorrectly it can be quite expensive to rectify.  We have spent hundreds if not thousands of hours Fibrelgassing and it takes attention to detail to get a great looking finish. 

If a GRP roof has been installed correctly and the repair is due to accidental damage then yes, very easily.  Here are the basic steps needed to complete the repairs. 

1, Sand and acetone the damaged area

2, Apply a layer of resin, followed by the matting, and then apply another layer of resin making sure to remove all air bubbles

3, Sand and acetone the area. then apply your top coat

If the top coat starts to peel away it can mean that the roof wasn't cleaned properly or that not enough top coat was applied which is the opposite for cracks.  If the top coat is cracking it means that it has been applied to thickly.

The only option for either scenario is to sand down the roof with 40grit sandpaper, clean with acetone and apply a new layer of top coat.   

GRP needs to be able to expand and contract freely during thermal warming and cooling.  The noises could be that the deck cannot do this due to the way the GRP has been applied.  If the roof deck and GRP has been applied correctly it could be that a trim is snagging on a brick or alike.