Why a GRP Flat Roof is a Great Option

“Your home should tell the story of who you are, and be a collection of what you love brought together under one roof.”

Nate Berkus

Your home is not only an enclosure that protects you from the world; it also provides you with a safe space to attach memories to. It is not only a physical investment but also an emotional one. Along with walls, the roof is the most important part of your home. It shelters you from the sun, rain, and all natural elements. In fact, a house ceases to be a house without a roof. When the roof holds this much value, it makes sense to take care of it by choosing the best materials for it. We recommend a GRP flat roof for exactly this reason.

What Is a GRP Flat Roof?

GRP stands for Glass Reinforced Polyester and is more commonly referred to as fibreglass. It is a material that is made using polyester resin and is reinforced with a chopped strand mat of glass fibres that form a GRP laminate. The idea of GRP being used as a roofing material has been around for more than 60 years. It has been popular not only because of its lightness but also as it is incredibly strong. GRP is durable, lightweight, flexible, fully reinforced, and waterproof. Plus, it can be moulded into any shape so it can be modified to fit any kind of roof. GRP flat roofs can be found on domestic buildings, corporate buildings, industrial buildings, and even warehouses. GRP flat roofs are constructed by applying catalysed resin on good quality roof decking; then, a fibreglass mating is laid on top and covered by a layer of resin. To weatherproof the roof and to give it an attractive finish, a layer of fire retardant resin topcoat is applied. Before actually applying the GRP to the flat roof, the edge trims and drip trims are connected to the edges of the roof to give it a clean finish and completely seal the roof.

Different Types of GRP Flat Roofs

There are five major types of GRP flat roofs that differ in materials and uses.

  • The standard GRP is ideal for houses and commercial buildings 
  • The GRP HD is more durable and is designed in a way that allows people to walk over it.
  • Direct Lay is a type of primer that is applied to existing surfaces such as concrete or asphalt and then the GRP system is laid on top.
  • PU is also known as polyurethane and is considered a high-performance GRP and is found on large corporate and commercial buildings.
  • Greentop is a type of flat roof that is designed in a way that allows you to create gardens and or green roofs on top of the roof itself. This might be a great area to raise your own fruits and vegetables.

Advantages of a GRP Flat Roof

One of the reasons GRP has become increasingly popular as a roofing material is that it has so many advantages. One of them is its durability. A typical flat roof is made to last 10 years but the normal life span of a GRP flat roof is close to 30 years! Usually, it does not even require any repair and upkeep. In case it does, reparations are easy to make because, unlike typical roofs, you don’t have to take apart a section of the roof to fix it; rather, reinforcement and a new layer of resin applied to the broken surface are sufficient.

“All work on roofs is highly dangerous, even if a job only takes a few minutes. Proper precautions are needed to control the risk.”

Another major advantage of a GRP flat roof is the installation ease. Typical roofing materials need to be heated to be shaped and fitted onto the roof but GRP is a cool process method which means there is no heat needed to fix the roof to the house. Roof installation is dangerous and we should try to make it as safe as possible to install. The house also doesn’t need to be vacated while the roof is being installed. Fibreglass is versatile and can be adapted to fit all types of roofs because they are flexible. Fibreglass roofs can be modified to allow natural sunlight to get through which means that they are also ideal for skylights. With all of these advantages, GRP is a worthy investment.

GRP Flat Roof Vs. EPDM

One major advantage GRP has over EPDM is its aesthetic appeal; it is clean, seamless, and found in a range of colours. One slight concern with GRP is that it needs to be installed in extremely dry weather. Since the weather in the UK is extremely unpredictable, plan ahead for the roofing to take place. While EPDM comes in sheets and can be installed in all kinds of weather, you need specialised tools to install a GRP flat roof. This is where the Family Roofing Company comes into the picture. 

EPDM is a rubber-like substance that can be used on roofs with uneven surfaces. It is incredibly versatile in the types of roofs it covers just like GRP. Both GRP and EPDM are waterproof and discourage moss and rot from growing on them. Both last about 25-30 years and need minimal upkeep. 

GRP and EPDM are both great options, whichever you choose depends on what your preference and what you are looking for. We suggest not going for the cheap and easy solution that EPDM is, and choose a GRP flat roof for a more aesthetic appeal and durability.


GRP is sturdy, long-lasting, aesthetically pleasing, and flexible. It is a great option for all kinds of buildings. This article details what a GRP flat roof actually is, what are its advantages, and how it holds up to EPDM as a roofing material. 


1. https://www.hse.gov.uk/construction/safetytopics/roofwork.htm