Round wooden pools

Installation requires a reinforced concrete slab 15 to 17 centimeters thick that is completely horizontal and level. The total weight of the water distributed around a circular perimeter creates pressure that can cause soft ground, compacted soil, or gravel to sink or become uneven.

Before pouring the concrete, it is advisable to check the following:

• Minimal excavation, leaving a 25 cm clearance around the outer radius of the pool.
• Install welded steel mesh to prevent cracks caused by structural tension.
• Allow the concrete to cure fully for 21 days before starting to stack the timbers.

A geotextile underlay is laid over this clean base to insulate the pool floor before the flexible liner is installed.

Class IV autoclave treatment permanently protects the core of the wood against fungi and wood-boring insects, so it will not rot even in direct contact with wet soil. However, ultraviolet radiation degrades the surface lignin, turning the wood a silvery gray.

To preserve the original golden color, simply apply a water-based wood stain or saturator once a year after cleaning the surface with a brush and pH-neutral water. If you need replacement parts or want to renew the inner liner after years of use, you can replace it directly with a Gre blue liner Ø 350x120 for round pools designed for standard circular pools.

The circulation system draws in surface water through a housing recessed into one of the precut slats in the upper wall. This factory-machined opening houses a key accessory such as the Skimmer + AR100 return nozzle, which traps leaves before directing the flow toward the pump.

The return nozzle sends the filtered water back into the pool, creating a continuous circular current. This natural centrifugal flow in round structures directs sediment toward the bottom suction point much more efficiently than in models with sharp rectangular corners.

A structure made of 45-millimeter-thick Scots pine boards provides incomparable thermal inertia and mechanical strength compared with a 0.4-millimeter galvanized steel wall. While metal dents from accidental impacts and quickly transfers the nighttime cold to the water, solid wood acts as a natural insulator, keeping the water two to three degrees warmer at dawn.

In addition, round wooden pools are self-supporting thanks to a closed, tongue-and-groove ring. They do not require protruding steel supports or bolts passing through the wall, which can rust due to chlorine or salt leaks, ensuring graceful aging and superior aesthetics throughout 2026.

The pump and filter must be able to turn over the entire water volume within a maximum of 4 continuous hours during the warmer months. For round pools with a capacity of up to 12 or 14 cubic meters, a compact unit such as the Star 300 sand filter with pump provides the required flow rate of 4 m³/h for optimal retention of suspended particles.

If the diameter exceeds 4.5 meters and the volume approaches 20 cubic meters, it is advisable to increase the filtration flow rate to 6 or 8 m³/h, using a silica sand or glass filter bed to ensure crystal-clear water while using less chemical disinfectant.

Completely emptying a wooden pool is a serious mistake because the water pressure keeps the tongue-and-groove walls snug and prevents the planks from shifting or drying out excessively. The technical procedure for passive winterization involves precise mechanical steps:

• Lower the water level to about 10 cm below the skimmer to drain the pipes and prevent frost damage.
• Add winterizing chemicals and distribute them evenly with the filter running in recirculation mode.
• Install ice-compensation floats on the surface to absorb expansion if the water freezes.
• Cover the perimeter with an opaque protective tarp secured to the exterior wooden anchors.

This way, the liner and the wood stay protected through the cold season without biological degradation.

Round models made of pressure-treated Class IV wood can be installed above ground, partially buried, or fully buried, provided the exterior perimeter is waterproofed. Continuous contact with soil does not rot certified wood, but it does cause lateral moisture buildup that must not push the pool shell inward when the water level drops.

To partially bury the structure, it is essential to install a drainage sheet with Delta-MS-type polyethylene dimples against the exterior wooden walls. In addition, the perimeter gap between the wood and the earth slope must be filled with clean gravel or free-draining crushed stone, without compacting it with heavy machinery, to ensure rapid drainage of rainwater to a drain well.