Flat roofing repair work

Case study: Glass fibre flat roofing repair work in Caerleon

With over 40 years of experience in the installation and repair of flat roofs, we encounter many that have failed at the early stage of their expected lifetimes -- less than 30 years. Most of these have lasted for under 10 years, proving very expensive to the customer.

You might have selected glass fibre (also known as GRP) as the waterproofing membrane to protect your porch, garage  or extension flat roof. If installed correctly, this is a high-quality, durable and leak-proof system with a 20-year guarantee.

Yet with most badly designed systems problems start after 3 - 5 years: 

  • You call the previous installer who is no longer trading; many poorly installed installations are performed by companies in business for only a few years - much shorter than the lifetime of a high-performance flat roof.
  • Even if you get through, the installer informs you there is no guarantee: one of the key things to look for in a flat roofing company is their guarantees - are they insurance-backed?
  • You're offered a 'quick fix' secondary repair job, where a  poor quality coating is applied.

Worse still, you engage another installer who also carries out another 'quick fix' that also fails as depicted in the photographs.

None of the above are acceptable; and it’s purely down to a very poor glass fibre roofing application.

As we see in the photographs, this is a common occurrence: 1 in 2 of the glass fibre flat roof repairs are because the initial installation has not been done properly. The most common cause is a sub-standard glass fibre laminate.

In this study, the customer had a glass fibre flat roof installed in 2009. Leaks began to occur due to various errors:

  • Timber decking was inadequately fixed with too few fixings and was not correctly secured into underlying joists. This resulted in movement and seam buckling as can be clearly seen in the photograph.
  • Glass fibre laminate applied onto wet or damp boards and/or with insufficient resin usage causing porosity (air pockets) to form.
  • Uneven or insufficient topcoat application that merely sunk through the porous areas of the base laminate leaving continued porosity.

Later in 2013 the flat roof began to leak in multiple sites, but the original contractor failed to respond. The customer then called a second contractor to repair the roof. Again, a poor quality remedy was applied, failing drastically in a short space of time, where the repair procedure:

  • Incorrectly applied a second top coat to the original surface in an attempt to seal the membrane.
  • Inadequate surface preparation: prior to application the surface should have been thoroughly sanded and cleaned to expose the underlying surface
  • Used an excessively thick application of topcoat, causing embrittlement and cracking allowing moisture to enter. During winter months this would then freeze, expand and encourage detachment from the original defective surface.

Obviously, continued ingress by the elements can cause timber work in some cases to deteriorate beyond repair resulting in a more expensive remedy solution. 

The solution: In October 2017 the customer called Strandek GRP Systems. We applied an overdeck system which involved:

  • Adequately preparing the existing surface and removing the loose debris.
  • Lifting and setting aside the lower courses of roof tiles to expose the layboard.
  • Establishing the position of the original joists.
  • Mechanically fixing new quality approved timber decking with correct fixings and procedures.
  • Applying the Strandek® GRP Flat Roofing System complete with all perimeter edge trims and dark grey topcoat.
  • Correctly repositioning tiles to to prevent rainwater entering the roof

This created a new, fully waterproof flat roofing barrier bearing no resemblance to the defective roof. The client then, on completion,  received an Insured Guarantee.

So if you’re probably asking yourself ‘where can I find a reliable flat roofing repair company?’, look no further:

At Strandek GRP Systems, you’ll have a flat roof designed to last decades or a simple leak repair by an experienced company that’s been installing flat roofs for over 40 years. This year we were proud to receive recognition of our services by being awarded a coveted 100% Customer Satisfaction Certificate from our insurance guarantee backers, the Independent Warranty Association.

Call us today on 01633 250652 or contact us here.

Flat roofing repair work

Why Choose Strandek®?

Since 1976, Strandek has provided high-quality glass fibre and other resin-based coatings to a range of satisfied customers in industry, government, construction and residential sectors alike. 


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