Flat Roof Construction – The UK’s No.1

Flat Roof Construction – The UK’s No.1

Flat roof construction is an area we have perfected at Topseal.

With decades of experience and products fitted across millions of square metres of roofs, we are firmly established as UK’s leading provider of flat roofing.

It is worth noting also that the National Federation of Roofing Contractors produced a comprehensive guide to flat roofing for those who are not experts in this field – home owners and those with business premises.

The guide, which we contributed to, goes into detail on all the different types of flat roof, what to look for, how to maintain them and also pitfalls to be avoided – including contractors who only have limited experience installing flat roofs.

The guide is available online and is a superb resource for anyone considering a flat roof.

As the guide states, the waterproofing will always be supported by a structural roof deck, this is usually timber and in turn supported on joists.

While not necessarily visible post construction, the quality of this supporting structure is of course important, any roof built to last for 30 years and more requires a solid foundation.

Flat Roof Construction – The Market Leading Product


There are different types of flat roof built upon this structure, but we wish to focus on the Topseal approach.

Our roofs use a hard wearing waterproof resin and then a top coat that makes a seamless whole, perfectly finished with edging detail. The resin and top coat are cold applied, this making the roofs suitable for any project and also removing all risk of damage being done to the existing structure.

Within the Topseal range there are then a number of roofing options, each one suitable in different scenarios.

The standard Topseal roof comprises a waterproof laminate with a 450g/m2 Topseal roofing grade reinforcement mat saturated with our roofing resin, a top coat then applied to this.

This standard product is still hard wearing enough to come with a 25-year guarantee for the materials and workmanship – in reality we expect any Topseal roofing installation to last a lifetime.

The standard Topseal roofing is suitable for the majority of projects, but there are also options that are even more durable – the Topseal HD and Topseal Double Top.

The Double Top, for example, can be suitable where the roof acts as a balcony or walkway, this a roof that comes with a 40-year guarantee.

As the name implies, the DoubleTop has two of the roofing grade reinforcement mats; the Topseal HD being the middle ground between these products with a single 600g/m2 reinforced mat.

Versatile Flat Roof Construction


At Topseal, we have developed a product called Direct Lay, this a cold-applied liquid flat roof that can often be used to repair a failed roof, utilising the existing structure and so simply going over the old roof.

This saves time and money and also greatly reduces upheaval, as an example, a business having a roof repaired in this way would usually be able to stay open with no loss of trade.

As mentioned in the Guide, the quality of installation is also key to flat roof construction – to quote the advice:

“Flat roofing is a skilled job requiring training, experience and safety precautions.”

Anyone fitting a Topseal roof has been through our training course and had their work quality controlled – given the length of our guarantees it is essential that all roofs fitted are of the highest quality; companies can only offer market-leading guarantees when there are rarely issues with their product or installation.

At Topseal, we are ISO accredited and BBA certified, this ensuring that any claims we make about our roofs have been independently verified.

We are also approachable!

If you want to learn about flat roof construction, the detailed guide truly is the place to start.

However, if you need to know further details about Topseal’s range of products or would like an obligation-free quote please do get in touch.

We have also provided some links to key information below.

Call us on 01423 886495 or use our Contact Form. 

Topseal – Key Information

Case Studies with examples of projects utilising our flat roofs.

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