Choosing a new roof is a significant investment and one that you should research thoroughly in order to find the best solution for you and your home.

Whether it is a garage, conservatory or flat roof extension, you need to be confident that your choice will give you peace of mind for years to come.

Below we have information to help you make the right decision for your home.

Flat Roof Materials Comparison Chart

Performance DemandsEPDM Rubber GRP Fibreglass
DurabilityDifferent grades and qualities available.
Edge trims formed by wrapping rubber around pieces of wooden batten.
Glass Reinforced Plastic (Fibreglass) is extremely tough (hard) at the expense of flexibility.
Seam Integrity / StrengthRequired solvent adhered (glued) joints around details, wall flashings, pipe penetrations etc.
Easily contaminated during installation - the most common cause of EDPM failture. EDPM 'cures' after installation, becoming stiffer, hard to join/repair.
The main advantage with GRP, seamless and jointless.
UV Sunlight & Heat ResistanceEDPM is resistant to UV radition and heat.GRP is resistant to UV radition but becomes lighter (weight) over time. Can be specified most colours.
Reaction to FireSome EDPM roofing membranes exhibit combustible characteristics.GRP has some fire resisting properties.
Transmission / Condensation
EDPM allows limited vapour transmission.GRP does not allow vapour transmission. The risk of condensation leading to damp can be higher with GRP, particularly over bathrooms and kitchens.
Elongation / Flexibility
Expansion / Contraction
EDPM is highly flexible and can cope with building movement.GRP is not designed to be capable of any measurable elongation or movement, but will withstand normal building movement through expansion and/or contraction.
AppearanceRubbery, only available in black, looks dark grey (unless painted white), can fade.Clean, seamless but "plastic" in appearrance. Can become mossy quickly, especially from existing gutters. Can be top coated in most colours.
InstallationRequires highly skilled tradesmen to install correctly. Requires, glued/taped joins, easily contaminted with dirt, moisture and/or old bitumen during installation, leading to early failture.Produced on site using polyester resin, glass fibre and rollers etc, can be messy, should only be attempted in totally dry. Weather at temperatures between 5 and 25 degrees. Very trong odour from styrene used in polyester resin, which is also highly flammable.

EPDM Flat Roofing

EPDM roofing relies on adhesives or bonding agents to keep each seam of overlapping roofing from leaking. If the bonding agent isn’t applied just right, you will have a leaky roof. There is also a common problem with bubbling when the EPDM roofing isn’t laid flat enough. Because EPDM roofing material is cheap and easy to purchase and doesn’t require specialized equipment to install, many roofers try their luck at this product and unsuccessfully so. The bottom line is: There are better flat roofing options out there than EPDM. PVC and TPO are recommended.


Weather Resistant Rubber Roofing

Premium EPDM is not affected by extremes of temperature. Installations are in varied climates – from the glaring sun of the Middle East to the freezing cold of Siberia and Alaska.

Superior Finish

The colour of a dark grey slate looks natural and doesn’t easily show dirt.

The smooth synthetic rubber finish does not require ballast or chippings that have an annoying habit of blocking gutters and downpipes. Premium EPDM does not support moss growth. It not only looks good on day one but also stays looking good even after 30+ years…

The additional thickness of Premium EPDM gives a superior finish especially important to maintaining and increasing your home’s value.

Flexible Rubber Roofing

Premium EPDM easily bends with no stress, to follow the contours of the roof, upstands to walls, check curb edges, skylights, pipes, terminations into gutters and the like. Premium EPDM has over 300% flexibility so will easily accommodate building movement.


Premium EPDM rubber roofing repels all moisture and does not suffer with age from cracking or crazing. Premium EPDM “breathes” allowing vapours to escape, thus preventing blisters.

Ecologically Friendly

Extremely ECO friendly materials all applied with little energy – Both Government and the International Kyoto Ecology agreement recommends EPDM rubber as Best Value sustainable eco – sound roofing.

Tried and Tested

The Premium EPDM rubber roofing system holds British Board of Agrement certification no. 02/3967 BBA – is designated by government to issue European technical approvals.


GRP Fibreglass Flat Roofing

Choosing a new roof is a significant investment and one that you should research thoroughly in order to find the best solution for you and your home. Whether it is a garage, conservatory or flat roof extension, you need to be confident that your choice will give you peace of mind for years to come.
Why choose a fibreglass GRP flat roof over a felt, rubber or other membrane roof?
Many people think of fibreglass roofs as a new idea, or untested technology but you may be surprised to learn that fibreglass is a proven roofing material that’s been used in the UK building industry for over 50 years. The quality of your roof has a huge impact on your home, it prevents costly water damage to both the structure and to your possessions. No matter how much attention you to pay to the rest of your home and property, if you have a poor quality roof all of your efforts could be wasted. This is why you need to think about the different roofing options that are available. There are plenty of roof materials and styles to choose from but the benefits of GRP flat roofing are likely to provide you with everything that you could need. There are two main benefits of choosing this solution over others that are available and they are the durability of the product and a watertight finish.


One of the biggest strengths of choosing a fibreglass GRP flat roof is the fact that these roofs are so durable. When it comes to finding the best value in a roof, durability and long-term costs will always be an important factor. Thanks to the state of the art materials and technology utilised in these roofs Parker Maythorn confidently offers a 30 year guarantee, GRP simply does not deteriorate at the rate of felt or rubber. An added benefit to the durability of the system is that these roofs require little or no maintenance due to the nature of the structure. The advantage is that there are no seams, joints or welds to provide opportunities for water to get in and for components to be damaged or weakened. Once the strong fibreglass layer is laid, a durable topcoat is rolled over the top creating a fully sealed surface. Installed correctly, water cannot penetrate through any seams. The continuous surface area provides a huge benefit when it comes to finding a roof that can be relied on for many years to come. These roofs are constructed to the highest standard and quality and offer peace of mind to home owners that cannot be matched by other products.


Fibreglass is trusted in many other industries where long life and complete water-tightness are essential. It is a material that is used to make the hulls of boats, including the RNLI lifeboats. Where there’s a seam, there’s the opportunity for water to penetrate. By the time you’ve spotted your flat roof is leaking, there will almost certainly be more damage than meets the eye. A GRP roof has no seams or joints where water can in to damage the structure of the roof and cause costly repairs to your home. Even ‘modern, high tech’ rubber membrane roof coverings are fundamentally flawed as they still rely on glued or welded seams Continuous testing of GRP roofs have shown that you can expect the laminate to last 30 years plus compared to the 10 years you can expect a felt roof to last, if you’re lucky. It is the long term, sensible, peace of mind solution.


Fibreglass can be moulded to any area, around roof lights, light wells and any other obstacles and so tricky areas are not a problem. They can be made non-slip if the area is to be walked on. While functionality is extremely important when it comes to finding the best roofing material, you also want to have a home that you are proud of and which makes the best possible first impression. GRP roofs are finished with pre-formed GRP edge trims and a topcoat that is available in a range of colours to blend in with your existing structure, you are not limited to one product or look. This style of roofing can also be used in conjunction with roof windows or used alongside balconies and walkways. No matter what style of home you have or what look you wish to achieve, this style of roof will have the answer.


A major problem that people have with their conservatory is that they struggle to use the room as much as they would like. On hot summer days it can be uncomfortably hot, while in the winter it is far too cold to use the room. At Parker Maythorn we believe that your conservatory was built to be enjoyed all year round. Parker Maythorn replacement GRP roofs are perfect for transforming your old conservatory into an affordable living space that can be enjoyed all year round. Stay cooler in the summer and warmer in the winter. It is a great value way to bring your conservatory back to life and is suitable for all types of conservatories. A Parker Maythrona roof replacement installed on your conservatory is designed to look and function like a permanent part of your home. Fully insulated with the plaster skimmed ceiling completing the stunning interior finish. With many first class installations, both domestic and commercial, you can be assured that once installed, you can enjoyed all the benefits with peace of mind.

When it comes to finding a roofing material or roofing solution that provides comfort and benefits over a lengthy period of time, a GRP roof scores highly in every aspect. We believe that the perfect roofing solution for your property is a fibreglass GRP flat roof. Please contact us for a no obligation chat about how we can help you.