By late October most liner pools in Ontario are covered for the winter. If this summer the liner faded above the waterline, pulled away from a corner, wrinkled on the floor or started losing water, it is probably the thing you are thinking about while the yard is quiet.
There are two ways forward. One is another liner made in a factory to your pool's measurements and hung in place. The other is a reinforced PVC membrane cut and welded to the pool on site, sheet by sheet. We do the second, so this article explains what actually changes for a pool that has always had a liner, and what you can do this winter so the work is planned before spring.
Factory liner and welded membrane, side by side
The table uses the manufacturers' own published descriptions, linked below it, and what we see on our jobs.
| Question | Liner made in a factory | Reinforced membrane welded on site |
|---|---|---|
| How it is made | A single layer of PVC, assembled in a factory to the pool's measurements and delivered as one bag | PVC with a polyester scrim inside, delivered in rolls and joined on your pool |
| How it fits the shape | It depends on the measurements taken before it was made | Each sheet is cut to the wall or floor in front of the installer |
| Steps, benches, corners | Part of the bag, or covered separately | Cut, shaped and welded by hand, one at a time |
| What lies under it | The floor and walls of the pool | A geotextile underlay over the floor and walls |
| Joints | Factory seams | Hot-air welds made on site, sheet to sheet |
| Drains, returns, lights, skimmer | Faceplates over the liner | Each one cut out and sealed with a flange |
RENOLIT's comparison of reinforced membrane and standard liner describes the standard liner as a single-layer sheet pre-assembled in the factory. SOPREMA's data sheet for SOPREMAPOOL FEELING gives the build of one reinforced membrane: 1.5 mm nominal thickness, polyester scrim, rolls 1.65 m wide and 25 m long, welded with a hot-air gun on clean, dry edges, listed for new pools and for renovating existing ones.
What the job looks like on a pool that had a liner
The order is the same as on a new pool, which is why our membrane installation page and the renovation of existing pools describe the same steps. On a liner pool it runs like this:
- We review the pool from what you send: where it is, how old the liner is, what went wrong with it, and photographs.
- The old liner is taken out and the walls and floor are looked at bare.
- Anything wrong underneath is put right before the new surface goes on. A membrane follows the shape it is laid over, so a soft spot or a ridge in the floor would show through.
- Geotextile underlay is cut to the floor, walls, steps and benches.
- The membrane sheets are laid and welded to each other, seam after seam.
- Steps, benches and corners are shaped and welded by hand.
- Every fitting gets its own cut and flange.
- The pool is filled.
Damir and Nadezhda do this membrane work themselves whenever they can, the two of them, from the first weld to the last flange.
The part nobody sees until the liner comes out
A liner hides the pool behind it for years. When it comes out, the owner often sees the floor and walls for the first time since the pool was built. Most of what turns up is ordinary: stains, old patches, a rough area where water sat behind the liner.
Sometimes it is more than that, and then the honest order of work matters. On one pool we know well, the owners had the problems under the surface corrected first, and the new membrane went in after. That pool, its leaking first season and how it ended up, is told on our membrane repair page. The lesson carries over to a liner pool: whatever is under the new surface has to be right before it goes on.
This is also why we don't price a pool from its area. Two pools of the same size can need very different preparation, and we only know which one you have after we have looked at it.
A winter checklist while the pool is closed
You don't need to open the cover to start. Most of what we ask for can be written down or photographed now, and a few things are easier to remember while the season is fresh:
- The pool's address, or at least the town, and how a vehicle reaches the yard.
- When the pool was built and when the current liner went in, if you know.
- What happened this summer: how much water it lost per week, where the liner pulled away, where it wrinkled.
- Photographs of the whole pool from each corner, taken in summer if you have them on your phone.
- Close-ups of the steps, any bench, the skimmer, the lights and the main drain.
- Anything done to the pool before: patches, a past leak repair, a new deck.
- When you would like the work to start next year.
Send it through the estimate form or by phone and WhatsApp. If something in your photographs needs a closer look, we can arrange a visit before the estimate is ready.
Choosing the new surface
A liner pool often gets its first real choice of finish at this point. We install reinforced membranes from RENOLIT, Poolside by CGT and SOPREMA, and we have sample books from all three, so you can see and touch the actual material rather than pick from a screen. Plain light blue, white, greys, stone looks, marble looks and mosaic prints are all on our membranes and colours page.
A textured, slip-resistant version exists for steps and benches; the SOPREMA sheet linked above is one of them, with an embossed surface. If you want to see how a finished step edge, a drain or a corner looks up close on our own jobs, the close-ups of steps, drains and corners show them without filters.
Our clients rate us 5.0 from 8 Google reviews, and our RENOLIT and SOPREMA certificates are published in full on the company documents page.
Questions owners of liner pools ask us
Can a membrane go into a pool that has always had a liner?
Yes. The old liner comes out and the membrane is laid over a geotextile underlay on the same walls and floor. Whether those walls and floor are ready is the first thing we look at in your photographs.
Do I have to wait for spring to get an estimate?
No. A closed pool can be described and photographed now. We read the history and the pictures, ask what is missing, and prepare the estimate so the work can be planned before the season starts.
Which colour should I choose for a liner pool?
There is no single answer. We have sample books from RENOLIT, Poolside by CGT and SOPREMA, and the pattern is chosen with you for the pool, the yard and the budget.