Home › Pool tips & guides › Fitting or replacing a liner
Fitting a liner takes preparation. Most defects (creases, poor centring, early stains) come from a step missed before or during filling. Here is the checklist given by the manufacturers.
- Base smooth, clean, disinfected (anti-fungal) and free-draining.
- Fit between 15 and 25 °C, ideally in sunny weather.
- Wall fittings: new gaskets, clamp when the water is 10 cm below the fitting.
- Filling: work out the creases, then metal sequestrant + TA.
- A liner that is filled and clamped counts as acceptance: check it first.
Before fitting: preparing the pool
- The base must be free of rough spots and dust: a grain of sand or a chip of concrete will end up marking or puncturing the liner.
- Disinfect it with an anti-fungal product to prevent mould under the liner.
- The base must stay permeable to let run-off water and condensation drain away.
- When renovating, clean and disinfect the filter media (sand, glass…), or replace it.
- All the gaskets on the wall fittings (skimmers, return jets, vacuum point, lights) must be new.
During fitting
- Handle the liner with care, at a temperature between 15 and 25 °C. Too cold, it is stiff; too hot, it stretches too much.
- Check that the liner is properly centred and that the steps are weighted if there are any.
- For a pool without steps that has a deep end or compound slope, find the fitting direction given by the manufacturer (marker strip on the deep-end side).
- The liner is fitted with slight tension: the water pressure then removes the small creases.
Filling
- Fill with suitable water (mains water). No untreated borehole water or water of unknown origin.
- Watch for creases while filling and ease the liner by hand to work them out.
- Clamp the wall fittings only once the water level reaches 10 cm below the fitting.
- Add a metal sequestrant and a TA increaser as soon as the pool is filled.
After fitting
Balance the water (pH 7.2 to 7.6, TA 100 to 175 mg/L) before starting normal treatment, then follow the care rules: our complete liner care guide.
Parts and accessories for fitting and repair
Find our liner beading, liner accessories (underlay felt, adhesive, rails) and our pool-filling products.
Frequently asked questions
At what temperature should a liner be fitted?
Between 15 and 25 °C, ideally in sunny weather. Outside this range, the liner is harder to handle and fit.
When should a liner's wall fittings be clamped?
When the water level reaches about 10 cm below the fitting (skimmer, jet, light). Not before.
Should the gaskets be changed when replacing the liner?
Yes. All the gaskets on the wall fittings must be new, otherwise leaks are common.
How do I remove creases from a new liner?
While filling, ease the liner by hand to work out the creases. The liner's tension and the water pressure do the rest. Check before clamping: a liner that is filled and clamped counts as acceptance.
What products should be added when filling a new liner?
A metal sequestrant and a TA increaser, then the usual products once the water is balanced.