FIFTH-FLOOR SIKA SARNAFIL & SKYLIGHT UPGRADES IN NW3
Many substantial Victorian and Edwardian townhouses across Hampstead Village, Belsize Park, and Fitzjohn’s Avenue feature high-level crown flat roofs perched four or five storeys above street level. On our recent Hampstead refurbishment, London Roofing Specialist stripped a perished fifth-floor flat roof back to the structural joists and installed a grey Sika Sarnafil single-ply membrane engineered with raised standing seam profiles and integrated Brett Martin skylights.
Standing Seam Profiles, Brett Martin Rooflights & Positive Falls
Before laying the new waterproofing system, our carpenters inspected the exposed timber deck for damp decay and fitted tapered firrings to eliminate water pooling. We then installed a continuous vapour control barrier, rigid PIR thermal insulation, and hot-air welded the Sika Sarnafil membrane around custom-built insulated skylight kerbs, flooding the top-floor rooms below with natural daylight.
HIGH-ACCESS SCAFFOLDING & WARM ROOF SYSTEMS IN HAMPSTEAD
Working at fifth-floor height on narrow, leafy NW3 streets requires careful planning, Camden council permits, and fully regulated scaffolding. Our NFRC-accredited flat roofers manage the entire access and weatherproofing package in-house, using flame-free installation methods that protect historic roof timbers.
Sika Sarnafil Standing Seam Single-Ply
Polyester-reinforced thermoplastic membranes with welded standing seam detailing that replicates traditional lead or zinc aesthetics.
Brett Martin & Architectural Glazing Kerbs
Custom-framed timber upstands and welded membrane collars for flat glass rooflights, pyramid lanterns, and roof access hatches.
Cold-Applied Liquid Polyurethanes & GRP
Seamless, fibre-reinforced resin systems moulded around awkward parapet walls, soil pipes, and recessed balcony thresholds.
Elastomeric EPDM & Multi-Layer Felt
Durable synthetic rubber and reinforced mineral felt systems for lower-level kitchen extensions, bay roofs, and garages.
Part L Thermal Insulation & Interstitial Condensation Control
Top-floor apartments and loft rooms beneath uninsulated flat roofs suffer extreme winter heat loss and summer overheating. By fitting high-density rigid insulation boards above the structural timber deck, we keep the rafters warm, stop internal moisture condensing inside the roof void, and cut household heating bills.
CROWN ROOF JUNCTIONS & 10-YEAR INSURED GUARANTEES
On Hampstead crown roofs, the flat central deck meets steep pitched slate slopes and tall brick chimney stacks. If the perimeter junction is poorly detailed, driving rain tracks straight beneath the membrane. Our craftsmen dress Code 5 milled lead flashings and welded perimeter trims across every transition between the Sika Sarnafil deck, the adjoining natural slates, and the masonry chimneys. Every completed flat roof carries a 10-year insurance-backed workmanship guarantee alongside manufacturer material warranties. View our wider North London roofing work.
Frequently Asked Questions: Flat Roofers Hampstead NW3
Why use Sika Sarnafil with standing seam profiles on a Hampstead property?
Many properties in Hampstead conservation areas require rooftop upgrades to respect the visual character of traditional metal roofs. Grey Sika Sarnafil fitted with welded standing seam ribs delivers the classic linear look of rolled lead or zinc at a fraction of the structural dead weight, while providing hot-air welded seam security and zero maintenance.
How do you prevent leaks around new flat roof skylights?
We never surface-mount skylights directly onto a flat deck. Instead, we construct an insulated structural timber kerb raising the glazing unit at least 150mm above the finished waterline, dress the Sika Sarnafil membrane right up the vertical faces of the kerb, and mechanically clamp the weathered Brett Martin frame over the top.
