▽ +09.00Waterproofing · Water-retaining structures
Pool & water-feature waterproofing
Pool shell waterproofing and concrete treatment before the finishes, then a flood test and handover.
Engineering view
What is pool and water-feature waterproofing?
A pool shell holds water under constant pressure and is crossed by many fittings: returns, skimmers, lights and ladders. The finish goes on top of the waterproofing, so a defect only shows once water is lost or damp appears around the pool.
The waterproofing follows concrete and joint repairs and is flood-tested before the finish. Fountains and lakes follow the same approach, with geomembrane liners for large water bodies.
Problems it solves
What goes wrong
Water loss from the shell
Losses beyond evaporation, through the shell, joints or fittings.
Leaks around fittings
Returns, skimmers, lights and ladders not detailed into the waterproofing.
Tiles and mosaic debonding
Water behind the finish when waterproofing and adhesive are not compatible.
Diagnose by symptom
From the system’s documented advantages
Key benefits
Bonds to concrete and tolerates damp substrates
Works on either side, depending on the product
Tiles bond well over it
Documented advantages of Cementitious waterproofing — every system also has limits, listed on its page.
Applications
Where it applies
- P.01
Swimming pools
Indoor and outdoor concrete shells and balance tanks.
- P.02
Fountains
Shallow basins with many details and fittings.
- P.03
Lakes & water features
Large water bodies, often lined with geomembranes.
Building condition
New or existing
New building
New pool: pour joints treated and embedded fittings set before waterproofing, then waterproofing and flood test, then the finish.
Existing building
Existing pool: find where the water is lost first (shell or pipework), remove the finish where damaged or entirely, repair the concrete and redo the waterproofing.
By technology
Available systems
- Sheet membranesPVC membranesA synthetic sheet with hot-air welded seams, suited to large and exposed roofs.
- Sheet membranesGeomembrane & HDPE linersPolymer sheets thermally welded on site to line lakes, large reservoirs and flood channels.
- Liquid-applied & liningsLiquid polyurethane waterproofingA liquid membrane that cures into a continuous, seamless rubbery layer, strong at details and penetrations.
- Liquid-applied & liningsPolyurea waterproofing (hot & cold)A fast-curing, tough polyurea layer, hot-sprayed with dedicated equipment or cold-applied.
- Cementitious & crystallineCementitious waterproofingPolymer-modified cementitious coats that bond to concrete, for basements, tanks, pools and wet areas.
How the system is chosen
| Situation | Suitable systems | Why |
|---|---|---|
| A concrete shell under tiles or mosaic | Cementitious Liquid PU | A flexible layer compatible with tile adhesive. |
| A shell needing a fast-curing high-performance layer | Polyurea | Depending on the specification and the finish. |
| A pool or basin with a membrane liner | PVC membranes | Welded PVC membranes. |
| Lakes and large water bodies | Geomembrane liners | A welded liner over prepared ground. |
A starting point only: the final system follows the inspection, the approved specification and the product TDS.
Layers
System build-up
System build-up4 layers
Cementitious waterproofing
Select a layer to see what it does.
Finish or protection
Render, tiles or a screed, depending on use.
Where designed
Second cementitious coatCore layer
Applied crosswise to the first, up to the specified thickness.
First cementitious coatCore layer
Brushed onto a pre-wetted surface, with tape or reinforcement at corners and joints.
Pre-wetted concrete
Saturated surface-dry, open-pored and with defects repaired.
A typical build-up for this application, top to bottom.
System page: how it works and its limitsBrand-neutral
Manufacturers & approvals
- Fosroc (Saint-Gobain)Approved applicatorCertificate
- AwazelApproved applicatorCertificate
- AIM IndustriesApproved applicator · Sister companyCertificate
- IzomaksApproved applicatorCertificate
We start from the engineering of the system, then the product. Manufacturers appear here only with their documented relationship; this does not imply a commercial partnership.
Before work starts
Surface preparation
- Honeycombing, tie holes and pour joints repaired.
- Returns, skimmers and light niches set before waterproofing.
- Surface pre-wetted or dried as the system requires.
Sequence
Installation process
Repairs and details
Joints, corners and every fitting.
Waterproofing coats
Floor and walls up to the coping level.
Flood test
Shell filled and the level watched for the specified time.
Hand over to finishing
With an inspection record.
Inspection & testing
QA/QC
- Details around every fitting inspected.
- Thickness or coverage measured.
- A recorded flood test before the finish.
What we avoid
Common failures
Fittings left untreated
Water escapes around returns and lights.
Finish before the test
Any defect then means removing the mosaic.
Waterproofing incompatible with the adhesive
Tiles debond over time.
Executed references
From our projects
Residential compoundMakeen 68
Al-Rayyan, Riyadh
Wahla projects
Al-Narjis and Dirab, Riyadh Region
Balance projects
Seven districts of Riyadh
Yamamah projects
Al-Safa, Al-Arid and Al-Muzahmiyah
Private villas and palaces
Several sites in Riyadh
Meyar projects
Riyadh and other sites
Go deeper
Technical references
Before you ask
Questions
When is a pool waterproofed?
After the concrete and joints are repaired and the fittings are set, and before the finish. It is then flood-tested before the mosaic or tiles.
What is the best waterproofing for a swimming pool?
A system made for permanent immersion and pool-water treatment — often a flexible cementitious membrane under the tiles or mosaic, compatible with the tile adhesive — with the construction joints, fittings and lights treated, then a flood test before the finish.
Is a pool waterproofed from the inside or the outside?
Always from the inside, because that is what holds the water — and also from the outside during construction if the pool sits below ground with groundwater, or above a room or occupied space.
How can I tell if a pool is leaking?
If the level drops faster than normal evaporation: stand a bucket of water on a step and compare the drop inside and outside it after a day. Damp or salts around the pool and cracks in the shell are other signs. The pipework is then tested separately from the shell.
Next step
A new pool, or a leak in an existing one?
Send the pool drawings and its finish for a detailed offer, or ask for an inspection to locate a leak.