SINGLE-PLY & WARM FLAT ROOF UPGRADES ACROSS SW20
Across Raynes Park, from 1930s Blay houses and detached residences on the slopes toward Coombe Lane to Edwardian family homes around Approach Road and West Barnes Lane, flat roofs protect rear kitchen-diners, side-return extensions, garages, and loft dormers. When ageing mineral felt blisters or old chipboard decking softens through damp ingress, ponding water quickly stains ceilings below. As an accredited flat roofer in Raynes Park, London Roofing Specialist strips perished coverings back to the bare structural joists to install engineered Sika and IKO single-ply warm roof systems.
Timber Deck Preparation, Tapered Firrings & Vapour Control
Before laying any new waterproofing membrane on an SW20 extension, our surveyor and roof carpenters inspect the exposed C24 joists and 18mm marine plywood substrate for wet rot or deflection. We install graduated timber firring strips to create a positive drainage fall toward the perimeter gutters, bond a continuous foil-faced vapour control barrier, and mechanically fix the warm roof assembly in strict compliance with UK Building Regulations.
PART L THERMAL INSULATION & ARCHITECTURAL SKYLIGHTS
Uninsulated flat roofs over ground-floor kitchen extensions and garden rooms in Raynes Park lose heat rapidly in winter and trap excessive solar heat during summer. By installing high-density rigid PIR insulation boards above the structural timber deck, we keep the roof timbers at a stable ambient temperature, eliminate interstitial condensation, and bring SW20 homes into full compliance with Part L energy standards.
IKO & Sika Sarnafil Single-Ply Membranes
Hot-air welded thermoplastic membranes delivering crisp perimeter detailing, high UV reflectance, and complete resistance to standing water.
Frameless Rooflights & Lantern Kerbs
Structural timber rafter trimming, insulated 150mm upstand kerbs, and welded membrane collars for flat glass skylights and pitched roof lanterns.
One-Piece EPDM Rubber & GRP Fibreglass
Seamless synthetic rubber sheets and resin-laminated fibreglass decks for Blay house garage roofs, bay window tops, and box dormers across SW20.
Cold-Applied Liquid Polyurethanes
Fibre-reinforced elastomeric coatings brushed around intricate brickwork junctions, soil pipes, and patio door thresholds.
Welded Upstand Collars & Code 5 Lead Apron Flashings
Skylights and masonry upstands fail quickly when sealed with basic mastics or poorly lapped felt. Our NFRC-approved installers form insulated timber upstands, hot-air weld custom single-ply collars around every rooflight frame, and chase stepped Code 5 lead flashings into adjoining brick walls for a permanent, watertight seal.
FLAME-FREE WELDING & 10-YEAR INSURED GUARANTEES
Traditional torch-on bitumen systems rely on naked gas flames that pose a fire risk near dry timber rafters, eaves fascias, and dormer frames. By contrast, our IKO and Sika single-ply membranes are fused using temperature-controlled hot-air welding equipment, creating a monolithic seam stronger than the sheet itself. Every flat roof replacement we complete in Raynes Park carries a 10-year insurance-backed workmanship guarantee alongside manufacturer material warranties. View our wider portfolio at londonroofingspecialist.co.uk/projects/all/.
Frequently Asked Questions: Flat Roofer Raynes Park SW20
Can you install glass skylights when replacing an existing flat roof in Raynes Park?
Yes. Stripping the old waterproof covering down to the joists is the ideal stage to double up the structural timber rafters and form openings for flat glass rooflights or a pitched lantern. Our team handles the structural timber framing, warm roof insulation, and welded perimeter flashing as one coordinated package.
How long does a single-ply flat roof last on a Raynes Park extension or garage?
While standard mineral felt typically degrades and splits within 10 to 15 years under UV exposure, an engineered IKO or Sika Sarnafil single-ply system remains flexible across all seasons and delivers an expected service life of 35 to 40 years with virtually zero maintenance.
