The price of a Desjoyaux pool depends on the size of the basin, the filtration system chosen, and the landscaping options. For a rectangular in-ground pool measuring 6 x 3 m with stairs, the average cost ranges between €13,000 and €17,500 including tax, installation included. This price serves as a starting point: the differences widen as soon as you add a heat pump, a tiled deck, or a reinforced liner.
Development tax and regulatory thresholds: the hidden budget of a Desjoyaux pool
Most pricing grids stop at the price of the basin and installation. The actual cost of a project also includes local taxes, which vary according to the surface area of the basin.
The flat rate for the development tax applied to pools is set at €251 per square meter in 2026, down from €262 per square meter in 2025. For a standard-sized basin, this tax represents several thousand euros, payable in one or two installments depending on the local authorities.
The surface area thresholds also condition the administrative procedures, and thus the associated delays and costs:
- A basin of less than 10 m² can generally be installed without prior declaration, which reduces the application fees and delays.
- Between 10 and 100 m², a prior declaration of works is required from the town hall, with a processing time of about one month.
- Beyond 100 m², a building permit may become mandatory depending on the local urban planning scheme, which lengthens the process and may require the involvement of an architect.
Before comparing quotes, it is therefore necessary to relate the cost of a Desjoyaux pool to the amount of the development tax applicable in your municipality. The DGFiP is now using aerial imagery to identify undeclared basins, with possible adjustments over several years.
Desjoyaux pool quote 6 x 3 m: breakdown by item
A typical quote for a 6 x 3 m in-ground Desjoyaux pool allows you to visualize the budget distribution between the structural work, waterproofing, and filtration.
| Item | Indicative Cost Excl. Tax |
|---|---|
| Marking, earthworks, slab | €2,000 |
| Assembly of structures, reinforcement, pouring concrete | €3,800 |
| Masonry for the deck | €1,000 |
| Backfilling, finishing, screed | €1,300 |
| Classic model coping | €1,200 |
| 75/100 liner | €1,500 |
| PFI 180 filtration system | €1,800 |
| RE 276 stairs | €1,200 |
| Start-up and verification | €1,000 |
| Subtotal Excl. Tax | €13,800 |
| VAT 20% | €2,760 |
| Total Incl. Tax | €16,560 |
The structural work (earthworks, structures, concrete) accounts for nearly half of the budget. In contrast, the integrated PFI 180 filtration system, specific to Desjoyaux, makes up about 13% of the total excluding tax. This item distinguishes the brand: filtration without buried piping simplifies installation and reduces long-term leak risks.
Options that increase the bill
A forum report (department 77) mentions a quote of €36,000 for a 7 x 3 m basin including a heat pump, safety cover, and 21 m² of tiled deck. The difference with the bare 6 x 3 m basin is explained by three items: the heat pump (several thousand euros), the safety cover, and the deck landscaping.
On its Facebook page, Desjoyaux displayed a price of €17,500 including installation for a limited promotional offer. This price corresponds to a standard basin without a heat pump or peripheral landscaping.
Annual operating cost of a Desjoyaux pool: filtration, water, and maintenance
The purchase price represents only part of the total budget. The annual operating cost covers the electricity for the filtration pump, water treatment products, partial water renewal, and periodic liner replacement.
The buried piping-free filtration technology reduces electricity consumption compared to traditional skimmer and piping systems. With a limited number of connections, pressure losses in the hydraulic circuit decrease, allowing the pump to operate at lower power.
Regarding maintenance products, the annual budget depends on the water volume, pool usage, and the quality of the local water supply. The recurring items break down as follows:
- Treatment products (chlorine, pH, algaecides): a budget to be planned each season, varying by region and pool exposure.
- Partial water renewal: local regulations and natural evaporation require regular level replenishment.
- Liner replacement: plan for a change every ten to fifteen years depending on the thickness chosen (75/100 or more).
- Electricity for the filtration pump: the integrated Desjoyaux system consumes less than a traditional piping circuit.
Desjoyaux pool and property value: a dual-entry calculation
Installing an in-ground pool increases the property’s land value, but also the tax base for property tax. The development tax, paid once, adds to this permanent reassessment.
For a medium-sized Desjoyaux basin, the increase in property tax depends on the municipal coefficient and the declared surface area. This annual tax increase should be included in the profitability calculation, especially if the property is intended for seasonal rental.
The ratio between the purchase price of the basin and the potential capital gain upon resale varies greatly depending on the geographical location. In areas where the demand for homes with pools remains strong, the investment is more easily justified than in regions where the market is less tight.
The total cost of a Desjoyaux pool is not limited to the initial quote. Development tax, property tax, and annual maintenance budget represent ongoing items that weigh on the overall project budget, sometimes as much as the basin itself over a decade of use.