CAWS fixes failed waterproofing across Perth: balconies, podium decks, rooftops, planter boxes, wet areas, car park decks and basements. We find out why the membrane failed before we replace it, then choose the right system for that part of the building.
What we waterproof
Balconies and podium decks, tiled or with a trafficable finish
Rooftops, roof terraces and plant rooms
Planter boxes on balconies, podiums and rooftops
Bathrooms and wet areas
Car park decks and ramps
Basements, lift pits and retaining walls, including from the inside. See basement waterproofing
Completed waterproof membrane across a large commercial roof deckConcrete stairs finished with a new waterproof coating
Why waterproofing fails
Most failures we investigate weren’t caused by age alone. They come back to how the membrane was installed: too thin, over a damp or dusty surface, with no upturns or bond breakers at the junctions, or never sealed into the drains. Cracks that weren’t treated first will also tear through a membrane over time.
What a waterproofing membrane is actually made of.
A lasting membrane is built in layers, each with a job to do.
Prepared substrateGround back, cleaned and repaired so the system bonds to sound concrete.
PrimerSeals the surface and gives the membrane something to grip.
ReinforcingBond breakers and reinforcing tape or fabric at corners, joints and drains, where movement and failures concentrate.
Membrane, two coatsBuilt up to the specified thickness. One thin coat is where many cheap jobs fall short.
FinishTiles on a bed, or a trafficable topcoat, protecting the membrane underneath.
A membrane is a system. Skip one layer and the rest can't make up for it.
The corner where most bathroom and balcony leaks start.
Floor to wall junctions take the most movement, so they need the most care.
The common fault. The floor and wall move slightly differently. Rigid grout cracks at the corner, and with no membrane up the wall, water runs straight into it.
Done right. The membrane turns up the wall, a bond breaker and reinforcing let the corner flex, and flexible sealant replaces grout at the joint.
The right system for each area
No single product suits every job, and using the wrong grade is a common cause of early failure. We choose after inspection, based on sun, traffic, the substrate and how the building is used:
Reinforced water-based polyurethane under tiles and screeds on balconies, podiums, planters and wet areas
UV-stable polyurethane where the membrane is the finished surface, such as roof terraces and walkways
Torch-on sheet membranes for plant rooms, large flat roofs and areas under pavers
Trafficable deck coatings for car park decks and ramps
Crystalline waterproofing (Xypex) from the inside, when the outside face can’t be reached
Torch-on sheet membrane being installed over a podium deckLiquid waterproofing membrane being rolled onto a commercial roof deck
How we approach it
Inspect. We look at the failed area, the space below, the drains and the junctions.
Find the cause. Moisture readings and testing show where water is getting in.
Scope and quote. A written scope with photos, explaining what failed and how we’ll fix it.
Repair. We prepare the substrate, treat cracks, correct falls where needed and install the new system with proper detailing at every junction and drain.
Hand over. We photograph the finished work, so you have a record.
Diamond grinding a rooftop deck to prepare the surface for a new membraneDecorative flake coating finished on a rooftop terrace
Common questions
Do the tiles always need to come up?
Not always. A failed junction, drain or seal can sometimes be repaired locally. A failed membrane under the tiles usually means lifting them. Our guide explains more: Why is my balcony leaking?
Can any membrane be left exposed to the sun?
No. Under tile membranes need to be covered, while UV-stable membranes are made to be the finished surface.
Can you work on an occupied building?
Yes. We plan works around residents and tenants, and write clear scopes for strata managers and owners.
Can you fix the water damage below as well?
Yes. Once the leak is fixed, we coordinate making good of damaged ceilings and finishes.
