Flat Roof Specification

Flat Roof Specification

Any flat roof, even the simplest, consists of several components and layers. This is generally what we mean by flat roof specification and it plays a vital role in new construction and refurbishment of existing roofs.

If you’re creating a simple roof for a shed, for example, it requires less support and can work with a simpler structure. If you are covering an office or warehouse building, then you need something more complex. A flat roof specification for a roof garden or walkway, again, will have different requirements.

What Makes Up a Flat Roof Specification?

Of course, there are variations for different buildings but the essential components of a flat roof specification could include:

  • A load-bearing, supportive structure below which is usually a ceiling.
  • A vapour control layer that helps reduce condensation levels.
  • The roof deck which is the construction onto which the upper membrane is going to be placed.
  • An insulating layer.
  • The protective waterproof membrane commonly referred to as the flat roof system.

Here at Topseal, we strive to provide our customers with products that are made to the highest standard. We also try to make your job of choosing the appropriate flat roof system a lot easier.

This is why we have gained numerous certificates from professional bodies and have joined with organisations dedicated to checking the quality of our services and products and have built a dedicated online specifiers area.

It can be a minefield to choose a flat roofing system for your projects as so many are available on the market. Topseal has a range of fibreglass flat roofing systems suitable for various flat roofing needs and the guarantees range for 20 years right through to a 40 year (with Topseal Doubletop).

Our standard flat roof specification has the following profile working from bottom to top:

  1. A 12 mm ply sub-deck with vapour check.
  2. Insulation layer.
  3. 18 mm OSB deck.
  4. Layer of Topseal roofing resin.
  5. Reinforcement mat.
  6. Top layer of Topseal resin.
  7. Topseal topcoat.
  8. GRP roof trim.

You can see how all this fits together as a flat roof specification here.

RIBA Product Selector

Many of the architectural practices that we work are members of the Royal Institute of British Architects, which is why we opted to have the Topseal systems in the RIBA product selector. Not only does this make accessing system details and technical information easier for you but this allows us to keep up to date with everything within the industry. It helps us to provide a more efficient service, which in turn helps our customers get the most out of each project. It means your flat roof specification is adhered to regarding construction and materials used.

National Building Specification (NBS)
Topseal has its range of systems available in NBS and this can be found through our website or through the NBS website. Topseal’s roofing systems come under J31 liquid-applied waterproof roof coatings and you can easily see the flat roof specifications and apply them to your project.

ISO:14001 Certified
Topseal has been ISO:14001 certified since 2013 and this helps us show we are committed to using a management system to help our company reduce its environmental impact.

The timber we use for the decking in our roofing systems, for example, is certified by the FSC (Forestry Stewardship Council), which helps the responsible management of forests across the world. Many construction and design companies nowadays apply strict criteria, including flat roof specification.

British Board of Agrément (BBA) Approved – No. 93/2932
Many developers that are looking at flat roof specification only look at BBA certificated systems. Topseal has a BBA (British Board of Agrément) certificate.

The BBA inspects and tests the quality of each of our products taking a close look at the flat roof specification. In real life, this helps you to verify that you are buying quality, an end product which has been tried and tested by independent professionals. You can view our certificate via the BBA website using reference number 93/2932.

ISO:9001 Certified
Along with the BBA certification, Topseal also holds ISO:9001 certification, which helps us to ensure that we meet all quality requirements related to all internal procedures. This certification lets our customers know that we aim and, are working towards, delivering the highest standard of quality. When it comes to flat roof specification, this ensures you are getting the high-quality, durable solution that your building needs, whether you’re a homeowner or a commercial property.

Specification Area
Our informative specification area is available for those who require access to technical details and drawings, as well as more in-depth information about each of our systems. It’s the ideal resource for all and it’s easy to access; simply register with us and we will send you your login in details.

To find out more about our flat roofing specifications or to talk to someone about your roofing project, call our friendly team direct on 08000 831 094.






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