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Equipped with a counter-current system and a hot tub, this rectangular pool is a delight for young and old alike. The basin is in turn in blocks to bancher, a technique accessible to all.

A swimming pool in blocks to bancher

Difficulty: Confirmed
Cost: 25 000 €
Time: 4 months (drying included)
Equipment: concrete mixer, grinder, grinder, puncher, clamp, handsaw and metal saw, hammer, dekameter, mason ruler, chalk line, level, plumb line, trowel, cutting pliers...

See the plan of this realization (in pdf): A pool in blocks to bancher: The plan

Among the many techniques to realize his swimming pool (polyester shell, kit, concrete banché, blocks, wood...), Jean-Michel Delgaire opted for the 20 x 20 x 50cm (Stepoc) bancher blocks. These calibrated formwork blocks are laid dry (without mortar) before being filled with concrete to form the walls. With free shapes, our reader preferred a calibrated rectangular basin without a diving pit, easier to implement. Measuring 4 x 11m and 1.45m deep, it incorporates a submerged rolling shutter, housed under a wooden beach.

Reinforced PVC liner

The equipment is completed by a counter-current swimming system. It is powered by a pump installed in a masonry reservation, made under the water level and closer to the pool to avoid pressure losses. A corner of the pool houses a hot tub: six nozzles propel the air sent by a blower attached to the wall of the technical room. On the coating side, our reader has chosen a reinforced PVC liner, the laying of which requires specific know-how: the strips are assembled by hot calendering. Its implementation has been entrusted to professionals (such as excavation).

Comfortable equipment

The technical room houses all the filtration, treatment and regulation systems. A pump of 17m3 / h of flow ensures the suction of water by 2 skimmers, 2 bungs and a broom. Filtration is guaranteed by a 14m3 / h sand filter. The chemical treatment is done by electrolyser and pH regulator. Finally, the pool is cleaned by a robot operating with booster pump.

Delimit the perimeter of the basin

Delimit the perimeter of the basin

The perimeter of the basin is delimited with the line and traced (bomb aerosol). The depth of the excavation (here, 1.72m) is determined at the laser level relative to a point 0, to keep the same height finished during the construction.

Ligate the tablecloths and seal the bungs

Ligate the tablecloths and seal the bungs

Two sheets of welded mesh provides the reinforcement of the base slab. They are ligated on the periphery of the first and in the direction of the width (center distance of 1m). The bungs are sealed before laying the second sheet.

Delimit the slab

Delimit the slab

The slab is delimited by a peripheral formwork (bastaings, h 25cm, 2.5cm thick). 200 vertical irons of Ø 8mm square, spaced 20cm apart, are tied to the lattices.

Spread and pull the concrete

Spread and pull the concrete

The reinforcement finished and the bungs caulked, the concrete (12m3) is spread in bottom of excavation with the rake and the shovel, then pulled with the rule of mason. Formwork and guide ruler serve as support during this operation. The thickness of the slab should be 25cm.

Build the walls of the stairs

Build the walls of the stairs

The first row of blocks is laid on a bed of mortar. The vertical steels of the intermediate wall are put in place after drying of the slab. The horizontal chaining consists of 2 irons Ø 6mm.

Mount the blocks and pour the concrete

Mount the blocks and pour the concrete

The blocks are laid at vertical cross joints. Four rows are installed before pouring the concrete (dosed at 350kg / m3), so as to spread it evenly inside the blocks.

Achieving horizontal chaining

Achieving horizontal chaining

Tors of Ø 8mm are inserted as and when in the continuity of the vertical irons already in place. A new horizontal chaining is performed in the same way as before. Then the following three rows are implemented.

Cut out the top of the last row

Cut out the top of the last row

The top of the last row is cut to accommodate the built-in elements: nozzles and brush plug (1.22m from the floor); swimming against the current (1.12m); projector, etc.

Embed the elements

Embed the elements

They are placed in projection of 2m compared to the blocks (which corresponds to the thickness of the coating).

Seal the pieces with cement

Seal the pieces with cement

All parts are then sealed with prompt cement: they must remain stable during installation and filling blocks.

Fill the lower blocks of concrete

Fill the lower blocks of concrete

Heavy and bulky elements, such as the counter-current swimming system and the skimmers, rest on a temporary support.

A swimming pool in blocks to bancher: blocks

The blocks below are filled with concrete to prevent the formation of air cavities when pouring the last rows.

Check the flatness of the walls

Check the flatness of the walls

The laying of the last rows continues. The flatness of the walls is checked with a spirit level and a mason's rule.

Raise the culmination of the bottom of the pool

Raise the culmination of the bottom of the pool

The highest point of the bottom of the pool is raised at the laser level. It determines the height of the formwork of the peripheral walls, maintained by clamps. The slightest slope can make the work unsightly.

Pour concrete

Pour concrete

After laying a steel chain, the concrete (dosed at 350kg / m3) is poured. The arase is simply smoothed to the rule by leaning on the formwork.

Realize the steps of the stairs

Realize the steps of the stairs

The steps of the staircase are made in the same way as the peripheral walls. Wider than the blocks, the rows separated by " empty Are scraped and filled with concrete.

Perform plumbing work

Perform plumbing work

Before sinking the mini-beach, the volume is filled with crushed gravel and falling rocks. The final height is materialized by a cleat fixed to the wall. During the drying of the stairs and the arase, the plumbing work is done.

Watertightness of the basin

Watertightness of the basin

A sealant is applied in two layers on the interior walls (roughing and finishing, total thickness: 15 to 20mm).

Pour a water-repellent tile

Pour a water-repellent tile

On the ground, a waterproof slab (4cm) is poured on the slab. At the berms, a slight slope (1.6m side) promotes the evacuation of water.

Set up swimming against the current

Set up swimming against the current

During drying (twenty days), swimming against the current is implemented.

Install the Hung rails for fixing the liner

Install the Hung rails for fixing the liner

Placed on the angle wall-wall (side basin), Hung aluminum rails allow the attachment of the liner strips. After removing a bead of Neoprene glue on the underside, they are fixed by riveting (rivets to hit). Their circumference is treated with silicone sealant to ensure perfect tightness.

Lay the liner

Lay the liner

The installation of the membrane begins with the vertical walls. Each lé is cut respecting a recovery of 10 to 20cm. The strips are then inserted as and when in the Hung rail which will be covered later with a PVC strip.

Weld the strips

Weld the strips

The welds between the strips are made with a hot air torch, type Leister (here, the staircase).

Put in water

Put in water

Once the entire pond is paved, impoundment can be done. Filtration, treatment and regulation systems must be started immediately afterwards.

Technical area

Technical area

In the technical room: the pump ensures the suction of the water, the filter, the electrolyser, the pH regulator and the booster connected to the pump.

Opening and closing valves

Opening and closing valves

Arrivals and departures can be opened or closed as required by valves.

Detect leaks

Detect leaks

In order to detect leaks, it is necessary to wait a few days before backfilling (20t of crushed gravel). The piping is "drowned" in fine sand (20cm) which also fills the formwork of the vertical pipes.

Shutter, coping and beach

Shutter, coping and beach

The motorization of the shutter is integrated in the winding axis of the deck. Two flanges fixed to the walls (stainless steel screws Ø 10mm) are secured to the axis by keying. The first module of 5 blades with stainless steel legs is slid into the dedicated groove.

A swimming pool in blocks to bancher: blocks

A beam (supplied) is fixed above the wall separating the flap of the basin. It is equipped with a notch to allow the installation of a slatted coating.

Open and close the shutter

Open and close the shutter

The opening and closing of the shutter is made from a key switch located near the control unit and power supply (technical room).

Glue the slabs of the coping

Glue the slabs of the coping

The slabs of the non-slip reconstituted stone coping (49 x 33 x 3.3cm), cut with a grinder and glued to the base (1cm joint), cover the Hung rails and the shutter fasteners.

Install the grating

Install the grating

The composite wood slats of the grating rest on the beam of the shutter and the arase (the margins to 3cm of the arase ensure the seat of the blades). The miniplage requires a disbursement of 30cm for a layer of gravel (15cm). The joists rest on blocks of agglomerates. A slope of 1cm / m to the outside allows the evacuation of rainwater.

to go

to go

On the opposite side, a small screed is poured and receives a reconstituted stone pavement identical to that of the coping. Expansion joints are inserted every 4m.

A perfectly integrated pool

A perfectly integrated pool

After four months of construction... The pool integrates perfectly with the environment and gives added value to the house.


Video Instruction: Construction d'une Piscine en Bloc Polystyrène IrriBloc de IrriJardin 7x4m