Flat and low-pitched roofs rely entirely on their membrane to keep water out. Unlike pitched tile or metal roofs, water sits on the surface for longer, so any crack, lifted lap or blocked outlet quickly becomes a leak into the building below.
We waterproof concrete roof slabs, roof decks, awnings and parapet gutters across Sydney, selecting membrane systems that suit the roof's exposure, foot traffic and budget.
Signs you need roof waterproofing
- Ceiling stains on the top floor after rain
- Blistering, cracking or peeling roof coating
- Ponding water that remains days after rain
- Moss, vegetation or debris build-up around outlets
- Cracks along parapets and upstands
- Leaks around air-conditioning units or roof penetrations
Roof membrane systems we install
- Liquid-applied polyurethane membranes — seamless, flexible and ideal for complex roofs with many penetrations
- Torch-on bitumen membranes — robust, reinforced sheets for large commercial roof areas
- Heat-reflective acrylic coatings — bright white finishes that reflect solar heat and help keep top floors cooler
- Trafficable systems — for roof decks and plant areas that need regular foot access
Roof waterproofing preparation
Surface preparation determines how well a roof membrane bonds and how long it lasts. We clean or grind the slab, repair cracks and spalling concrete, remove loose coatings, form coves at upstands and prime the surface before any membrane is applied.
Outlets, parapets and penetrations
Most roof leaks start at the edges and openings: rainwater outlets, parapet cappings, plumbing vents and equipment stands. We reinforce and seal each detail and can install overflow provisions so a blocked outlet does not flood the building.
Maintenance matters
A simple annual inspection and clean of gutters and outlets can extend the life of your roof membrane considerably. We offer maintenance inspections for strata and commercial clients.
Our roof waterproofing process
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1
Roof survey
We inspect the roof, test for moisture and identify failed areas, outlets and details.
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2
Repairs & prep
Cracks, spalling and loose coatings are repaired; surfaces are cleaned, ground and primed.
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3
Detail reinforcement
Outlets, upstands, parapets and penetrations are reinforced with compatible fabric and sealants.
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4
Membrane application
The selected membrane system is installed to the manufacturer's thickness and coverage.
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5
Inspection & handover
We check coverage and terminations, clean up and hand over maintenance guidance.
Why choose us for roof waterproofing
Systems for residential and commercial roofs
Heat-reflective options to reduce solar heat gain
Thorough substrate repair before membranes
Outlet and overflow detailing
Safe work practices at height
Maintenance inspections available
