If you have had a flat roof for a number of years, perhaps it was installed when your home was built and it’s showing signs of wear and tear, you may be wondering what options you have for a replacement. Before you start looking around for quotations it’s a good idea to have in mind what sort of roofing system you would like to replace your existing one. There are now lots of different materials available from felt to rubber and fibreglass. If you don’t know what the difference is between these materials, or what system would be right for your home, this guide will introduce you to some of the options that are available.

Flat roofing is different from traditional pitched roofing systems in that they are completely level. The nature of flat roofs mean that they are prone to weathering and leaks if the right material isn’t used. While the surface should be level, it needs a slight angle to enable rainwater to drain away. The fall should be around 1:40 but some roofs can be as much as 1:80 depending on the site that the structure has been built on. Flat roofing wasn’t traditionally used before the Second World War. As a mass house building project started, builders needed an affordable alternative to pitched roofing.

Flat Roofing Materials

There are many different flat roofing materials that can be used and the one that you choose for your property will often depend on personal preference. One of your main considerations should be the guarantee provided by the manufacturer and of course, the price. The material that you choose should have a 20 year guarantee at least to maintain its longevity. Once you have determined which flat roofing system you would like other things such as the performance of the material the structure and the appeal from an aesthetic point of view.

Torch on Felt

Felt is a traditional roofing material but today’s felt is much more effective than the traditional forms of felt that were applied using tar. The felt is supplied in a two or three layer bitumen sheet and this is applied using a gas torch to melt the bitumen and form a strong bond to the underlay which is installed on top of the decking boards. One of the main benefits of felt roofing is the cost, its flexibility and its ability to be applied in multiple layers.

Rubber Roofing (EPDM)

This is a common choice for roofing teams as it offers incredible flexibility and durability. It also protects against UV light and offers protection against water which is one of the main issues with flat roofing. Rubber roofing is also easy to install, and it can be effectively cut to size to neatly fit any flat roofing space. The EPDM membranes can last up to 50 years if correctly installed. The EPDM material is a single ply rubber which can be fitted without any joins, creating a seamless and aesthetically appealing roof covering. It is safe to install, and the synthetic rubber is glued to a clean roof decking surface using a wet bonding adhesive and a stronger contact adhesive which is applied around the edge of the roof. Trims are fitted around the edges to properly waterproof the structure resulting in a clean, smooth finish.

Glass Reinforced Polyester (Fibreglass)

This is the most expensive option and it is applied to the surface of the roof as a liquid which gives it greater flexibility during the installation process. It also works well on roofs that are unusually shaped. Even though it’s very lightweight it offers the durability and strength that you need for a flat roof covering. Fibreglass is made from a GRP laminate which is a specially formulated liquid roof resin and reinforcement mat. The laminate is fitted securely over the decking boards and then coated with a topcoat.

Green Flat Roofing

If you want a flat roof with a difference, you can install a green flat roof kit. This is a type of living roof which includes a layer of vegetation that is placed on the roof. They are great for city areas where there is a planning requirement for flat roofs while creating green spaces and a habitat for birds, butterflies and insects. Green roofing is an effective natural insulator and it can help you to reduce energy costs and save money too. As the green flat roofing system works to regulate heat, it will keep your building cool in the summer and warm in the winter which is a cost saving on your energy bills. It also helps to reduce sound too.

Benefits of Flat Roofing

A flat roof has a number of benefits including price, aesthetic and maintenance making them a great option.

The Design – Flat roofing is usually installed for smaller structures including garages and sometimes extensions. Waterproof membranes will protect the structure underneath (usually made from wooden decking and joists) while collecting water and then directing it into the guttering system and downpipes.

The Cost – When flat roofs are constructed, the cost of building the roof and also replacing the roof coverings is often much cheaper when compared to pitched roofs. The time it takes to install a flat roof is also much quicker than a pitched version.

Maintenance – Flat roofing can be easier to repair and inspect than pitched roofs which means that roof inspections can be undertaken on a regular basis. If you get into the practice of cleaning gutters and checking the structure will make sure that your roof stays in optimum condition for a much longer period of time.


After reading this guide you should be better informed about which flat roofing system is best for you. If you have any questions or concerns about roofing, please contact us and one of our roofing specialists will answer all of your queries.