Flat Roofing Repair

Save money and protect your property

Leaking flat roof? Need a high-quality repair that doesn’t require a full replacement? Look no further.

We’re able to diagnose and repair small leaks and oversee full replacements. Our systems are designed to save you time and money.

Operating throughout South Wales, from Cardiff to Newport, Monmouth, Abergavenny and Chepstow, we have over 45 years of experience in the repair and installation of flat roofs.

Call us today on 01633 250652 to find out more.

 Contact us



  • Unblock your gutters: when leaves build up in your gutters, rainwater overflows into the adjacent roof causing a leak. Remedial work usually involves unblocking and performing simple, cheap repair work.
  • Patch-up: punctured areas require urgent repair to prevent water ingress. This is common on single ply and older roofing systems with more fragile membranes. For patch up work, we recommend glass fibre and liquid-applied systems – these are perfect for any substrate.
  • Overlays: constant wear and tear can degrade weaker roofing membranes. Overlays are ideal for any flat roofing substrate with intact insulation and decking. Glass fibre, single ply or liquid-applied systems are ideal – with extensive guarantees they have expected lifetimes exceeding 30 years.
  • New flat roof: damage to the insulation and structural decking often necessitates a full replacement. Choose from glass fibre through to single ply and liquid-applied systems. Extensive guarantees and expected lifetimes greater than 30 years.


  • 20-year Strandek® guarantee on all repaired and refurbished roofs
  • 15-25 year manufacturer’s guarantees available
  • 10-year insurance guarantee from the Independent Warranty Association.
  • BBA-certified systems available
  • Installed by friendly, experienced technicians
  • Rapid installation, minimal downtime and professional service
  • High-quality: CE-marked materials from ISO-9001-grade suppliers
  • Optional UV-resistant materials
  • Full, comprehensive report with photographic evidence detailing the external and internal condition of your roof


Additional options

Most roofing systems are compatible with our green roofs, which offer great aesthetics and improved insultions.

Case Studies

How to avoid costly flat roof repairs

Flat Roof Repair Services

Roofing material

A range of flat roofing materials have been used over the past few decades. Some of the most problematic ones centre on mastic asphalt, felt roofing systems, EPDM rubber, bitumen roofing systems 

In the event of a leaking roof, one of the services we do recommend is a roofing survey. This can provide an assessment of the entire roof condition, as well as help identify the location and extent of any damage to the roof. If caught early – via flat roof maintenance – a patch repair or overlay – could be implemented – before the leak spreads to more integral parts like the roof timbers and underlying roof deck. This would reduce any flat roof replacement cost quite substantially.

Some of the most problematic flat roofing systems include felt and EPDM roofs – often used to provide waterproofing to a garage roof. As well as containing asbestos, a felt roof typically has a shorter lifetime and is often susceptible to solar-induced damage. EPDM membranes (and other types of single-ply like PVC) are perhaps more problematic to repair. Soft and easy to puncture (like a bicycle tyre), these rubber roofing systems are fragile and can allow water damage to occur quite easily. Most of our emergency roof repair work centres on leaking rubber roofs.

Sedum roofs, a type of green roof, create added complexities since the entire sedum needs to be taken up for the leak to be detected. For single-ply membranes, this is a big problem – a flat roof leak in the membrane will often gradually spread, causing significant damage over time before the leak has been detected. This is because a single-ply roofing system is mechanically fixed or glued to the underlying structure. A superior system is fibreglass since the laminate is bonded to the underlying timber, preventing a leak from spreading, should it occur. 

More modern ones have focussed on liquid-applied roofing membranes like polyurethane and fibreglass. Both of these are durable options, with fibreglass (GRP) flat roofing being the tried and tested flat roof material for repairs. Indeed, fibreglass flat roofs, when installed correctly, offer 30+ years of waterproofing. The polyurethane roof coating is quite a flexible option, but its durability over the long term is unknown – purported as a flat roof repair kit, they often suffer from poor adhesion and lower abrasion resistance. 

Frequently Asked Questions (FAQs)

Q. Is EPDM better than fibreglass as a flat roofing system?

A. No, EPDM is a softer material that is quicker to install but also quicker to fail. Unlike fibreglass, EPDM sags and creases and can puncture easily. If you plan to have workmen (window or gutter cleaners) on your roof, be very careful.

Q. How much does a new flat roof cost?

A. On a per square meter basis, a new flat roof can cost around £750 to £5,000 for most properties – ultimately depending on the scale. Added costs might include asbestos removal.

Q. How much is a flat roof repair?

A. A flat roof repair can cost anywhere upwards of £100 to £3000 on average. When the external membrane has failed, some property owners may wish to consider an overlay or overdeck – a technique that applies a new flat roofing system without replacing the costly insulation and timber decking. 

Q. Can I make a flat roof repair myself?

A. Yes, DIY repairs to flat roofs are possible. An understanding of the extent of any water damage is important and so a flat roof survey is recommended. This is a cheaper option than hiring a roofing contractor. In addition, Strandek recommends Resin Library’s Fibreglass (GRP) Roof Repair Kits as these contain required tools and materials needed to make a reliable repair.

Q. Which is the best flat roof surface

A. Fibreglass is an excellent all-round with excellent mechanical and waterproofing properties. Cost-effective and highly durable, it sits above many other flat roofing materials.

Q. What are the regulations on flat roof repairs?

A. Part L building regulations provide detail relating to flat roofing work. Generally, a modification to 25 % or more of the flat roof area necessitates a new flat roof and insulation upgrade. Flat roof overlays and over-decks can be a workaround and can save cost – these involve the application of a new membrane and associated decking in some instances on top of the existing roof. 

Additional detail in regards to planning permission is available for re-roofing and new roofs

Health & Safety

Undertaking any type of flat roofing work yourself is a dangerous task. Please plan ahead and ideally arrange a roofing survey from a professional. The UK Health and Safety Executive (HSE) provides very useful information on roofing work, providing guidance on working at height, manual handling, dealing safely with asbestos (e.g. in roofing felt or roofing cement as well as associated gutters and roofing sheets.

As an expert roofing contractor, we have experience in dealing with all types of flat roofing. 

Waterproofing is an important part of any building work – concrete and timber have excellent structural properties, but they are highly porous. As such, effective systems like fibreglass are commonly used to provide long-term protection.

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Case Studies

Flat Roof Repair


Leaking Flat Roof Repair


Leaking Flat Roof Repair

We are specialists in the repair and upgrade of leaking flat roofs. We only use the highest quality materials and offer a full range of comprehensive guarantees. Call us on 01633 250652 for a no obligation quote.

Let's get that leak fixed

Our Services

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.


Our team have extensive experience and we pride ourselves on reliable workmanship and competitive pricing.

  • Unrivalled service
  • Exceptional quality
  • Unmatched speed

Health & Safety

A strong health & safety ethic is the core of our business. We strive to maintain this through:

  • Best practices
  • Transparency & accountability
  • Rigorous training