Concrete water tanks, pools, fountains and wet structures need a durable inner surface that keeps water in and protects the concrete. GRP (glass reinforced plastic) lining provides a seamless, watertight layer that resists corrosion and is easy to clean.
What is GRP lining?
GRP lining is built up on site from layers of resin and glass-fibre mat, laminated directly onto the prepared concrete surface. It is finished with a smooth topcoat (gelcoat). The result is a continuous lining with no joints for water to leak through.
Benefits
- Seamless and watertight, with no joints to fail.
- Corrosion and chemical resistant.
- Hygienic: smooth surfaces resist algae and bacteria, and food-grade systems are available for potable water.
- Long service life with simple maintenance.
- Repairable: damaged areas can be patched and re-coated.
Typical applications
- Potable and fire water tanks.
- Swimming pools, balancing tanks and water features.
- Irrigation tanks and wet wells.
- Drip trays and chemical bunds.
Key steps for a good result
- Fully cured, dry concrete with a properly prepared surface.
- Correct laminate thickness for the application.
- Careful detailing around pipes, corners and openings.
- Proper curing before the tank is filled.
GRP lining vs other options
| Option | Notes |
|---|---|
| GRP lining | Seamless, corrosion-free and repairable |
| Cement-based coatings | Lower cost, but can crack and need recoating |
| New GRP tank | When the old structure is beyond repair – see GRP water tanks |
Inspection and maintenance
Inspect the lining every year, clean the tank to the operator’s schedule, and patch small damage early, before water gets behind the lining.
Related GRP products
GRP ladders for tank access, GRP seal plates for airtight covers, and GRP lamination for steel and concrete structures.
Planning the work
The tank must be drained, cleaned and dried, and the concrete repaired before lining. Allow time for curing before the tank is refilled.
Frequently asked questions
Is GRP lining safe for drinking water?
Food-grade systems are available for potable water tanks.
Can an old tank be lined instead of replaced?
Often, yes, if the concrete structure is sound.
How long does GRP lining last?
GRP lining has a long service life with simple maintenance and can be repaired if damaged.
Discuss your project
Our team handles GRP lining, tanks and custom GRP items. See our GRP fabrication.
Related: GRP Lamination & Coating · GRP Water Tanks
Related products: GRP fabrication · GRP seal plates · GRP lamination and coating