On Friday, 13 February 2026, an amendment to the Act on the Protection of the Rights of the Purchaser of a Residential Unit or Single-Family House and the Developers’ Guarantee Fund (the so-called Developers’ Act) entered into force. Its purpose is to eliminate a practice used by some developers—namely, including the floor area under demountable partition walls in the usable floor area of an apartment.
Under the new rules, the usable floor area of an apartment or house is to be determined in accordance with the provisions of the Polish Standard governing the definition and calculation of floor-area and volume indicators in construction, in force on the date the application for a building permit is submitted or the construction is notified. That standard explicitly prohibits counting partition walls (i.e., removable walls) as part of the usable floor area.
All indications are that the entry into force of these provisions will not only fail to end the ongoing dispute among lawyers about the date from which including the area under partition walls in the price calculation became inconsistent with applicable law—it may also create real confusion in new offers.
The Polish Association of Developer Companies (PZFD) points to 19 September 2021 as the date from which the area under partition walls should no longer be included. Lawyers disagree with that interpretation, arguing that the cut-off date should be September 2020. It is worth noting that some law firms representing buyers who purchased developer-built apartments before 2020 claim that there was never any legal basis for including the area under partition walls in the usable floor area.
Paradoxically, the new regulations settle the dispute over the method currently in force for calculating usable floor area, while simultaneously intensifying the debate over the legality of past practices. Courts will decide who is right in proceedings that are already underway.
It is also worth highlighting that the way the legislature chose to resolve the partition-wall issue has raised new doubts—this time regarding whether the usable floor area in apartments and single-family houses should include the area under staircases and the area under so-called sloping ceilings (attic slopes). While resolving the staircase issue should not lead to major differences in the total price a buyer must pay, the treatment of areas under sloping ceilings could materially affect statistics expressed as PLN per square meter in the market for new single-family and terraced houses.
Under the Polish Standard currently in force (PN-ISO 9836:2022), the usable floor area of a residential unit is not reduced due to room height. In practice, this means that the areas of houses offered by developers may “grow” by anywhere from a few to several dozen square meters simply by adding to the usable floor area those parts of a floor where the ceiling height is below 2.2 meters.
Publicly available analyses of the impact of the new regulations in the housing segment indicate that the usable floor area in individual offers could increase by 10% to as much as 30%.
To illustrate the potential effects of including additional space when calculating the usable floor area of a house with sloping ceilings, we will assume an average increase of 15%. The analysis uses data from a January monitoring of the market for developer-offered houses in Warsaw and Poznań.
At the end of January, the average developer-offered house in Warsaw had an area of 148 m². As a result of the changes in how usable floor area is determined, its listed area would rise by 15% to 170 m². The effects on average asking prices resulting from such a “correction” could follow two paths. The first—and more likely—is that the total price of the house remains unchanged, and it continues to be offered at PLN 1.874 million, but the price per square meter is (artificially) reduced from PLN 12,613/m² to PLN 10,807/m². The second—and less likely—assumes that the price per square meter remains at the same level. In that scenario, however, the total price rises in line with the increased listed area. The house would still be priced at PLN 12,613/m², but the total price would (artificially) increase from PLN 1.874 million to PLN 2.148 million.
Meanwhile, the average developer-offered house in Poznań at the end of January had an area of 113 m². Under the new approach, its area would increase by 15% to 130 m². This change could affect average asking prices in two ways. The first—more likely—is that the total price does not change. The house would still be listed at PLN 1.227 million, but the price per square meter would be (artificially) reduced from PLN 10,925/m² to PLN 9,470/m². The second—less likely—is that the price per square meter remains unchanged, while the total price increases in proportion to the larger listed area. The house would still be offered at PLN 10,925/m², but the total price would (artificially) jump from PLN 1.227 million to PLN 1.416 million.
The key question is: what will change—price per square meter, or the total price? If total prices are maintained, we will see a statistical decline in prices per square meter. If, however, developers maintain their per-square-meter rates, the cost of buying houses will rise significantly.
