Underground house: planning permission in Poland 2026

Which rules apply and who grants consent

House building is governed by the Construction Law together with the local plan or the planning decision. Applications and notifications are handled by the starosta (district office), in cities with district status by the mayor, and in Warsaw by the district office. Documents can be filed on paper or through the e-Budownictwo portal.

Building permit or notification

Notification with a design (Article 29(1)(1)): a detached single-family house whose area of impact falls entirely within your own plot. The design submitted is the same as for a permit. The authority has 21 days to object; if it does not, you can start. A site manager and a construction log are required.
Building permit: required where the area of impact extends beyond the plot, where a derogation from the technical rules is needed (Article 9, available only in this procedure), or where the authority imposes the obligation in response to a notification. The authority has 65 days to decide; a permit lapses if construction does not begin within 3 years.
House of up to 70 m² of built-up area (Article 29(1)(1a)): two storeys at most, built for your own housing needs, work may start once the notification has been delivered, and a site manager is optional. A family underground house is usually larger.

No stamp duty is payable for a permit or notification for a single-family house, provided no business activity will be carried on in it (gov.pl).

The plot comes first: local plan, general plan, planning decision

If the plot is covered by a local spatial development plan (MPZP), the design must comply with it; it is worth ordering an extract and a map excerpt from the municipality. Without a plan you need a planning decision (WZ). Following the 2023 planning reform, municipalities were to adopt general plans by 31 August 2026. For applications filed from 1 September 2026, a WZ can as a rule be obtained only where a general plan is in force and the plot lies within an infill development area (Article 61(1)(1a)). At the end of August roughly one municipality in three had a general plan. A WZ decision lapses after 5 years.

What to check in the plan for an underground house

Roof geometry: plans and WZ decisions often require a gable roof at a specified pitch. A flat green roof may conflict with this; it is the most common obstacle.
Height and number of storeys: a house set into a slope usually sits low, but what matters is how the plan defines the measurement.
Biologically active area: a green roof of at least 10 m² counts at 50% (§ 3(22) of the technical requirements).
Building lines, land form, nature protection and information on landslides and groundwater.

Before buying a plot, check whether the municipality has a general plan and which zone the plot falls in (Geoportal, the municipal office), and ask a designer for a short analysis of what can be built there.

What is specific to an underground house and how it is resolved

Important in 2026: the 2002 regulation on technical requirements ceased to apply on 20 September 2026 and the new one has not been published (as at 29 October 2026). For 18 months from 20 September 2026 the design is prepared under the previous rules once the client's declaration has been submitted (Article 102a of the Construction Law). The paragraphs below come from those rules.

Room floors no lower than the ground beside the building

Under § 73(1), in rooms intended for prolonged occupancy (more than 4 hours a day, that is rooms and bedrooms) the floor must be at or above the level of the ground beside the building. The exception in paragraph 2 covers service and production premises, not dwellings. Ground level means the ground elevation adopted in the design (§ 3(15)).

The solution: rooms and bedrooms sit along the open, glazed facade, with the ground in front of it at floor level, for example on the slope side or facing an excavated terrace. Deeper inside, below ground, are the bathrooms, wardrobes, pantry and plant room. A design in which a bedroom has no ground at floor level in front of it is worth discussing with the authority before filing the application.

Daylight: 1:8 and sunlight

§ 57: the window area (measured within the frames) must be at least 1/8 of the room's floor area.
§ 60: at least one room must receive 3 hours of sunlight on the equinox days (7am to 5pm), which a south-facing facade makes easier.
§ 13: structures obstructing a window within a 60° angle must stand further away than their own height. The retaining walls of a narrow patio can breach this condition, so the patio has to be wide enough.
§ 72: clear room height of at least 2.5 m.

Escape routes and fire safety

Fire resistance class requirements do not apply to single-family houses of up to three above-ground storeys (§ 213). Every room must nonetheless have a way out to a safe place outside (§ 236). In a house dug into the ground it is sensible to plan a second exit, for example a door on the other side or stairs up through a rooflight.

Distances from the boundary

A wall with windows must stand at least 4 m from the boundary, a wall without windows 3 m (§ 12). For the part of a building lying entirely below the surrounding ground, no distance from the boundary is set (§ 12(9)). Building closer to the boundary usually means the area of impact takes in the neighbour, and then a permit is required.

Structure, water and radon

The structure carries the earth pressure and the weight of the soil on the roof; the calculations are in the technical design, based on ground investigation under the regulation on geotechnical conditions.
Sections 316–317 require protection against groundwater and damp: drainage, waterproofing or watertight concrete built as a white tank.
Radon: the reference level indoors is 300 Bq/m³ (the Atomic Law). A sealed concrete slab and walls, together with continuous ventilation, limit how much gets in.

Energy performance

A single-family house has to meet an EP figure for heating, ventilation and hot water of up to 70 kWh/(m²·year) and U-values of 0.20 for walls, 0.15 for roofs and flat roofs and 0.30 W/(m²·K) for floors on the ground. Once the build is complete you need an energy performance certificate; a copy goes with the notice of completion.

Who signs the design and what documents you need

The architectural design is prepared by an architect with building qualifications who belongs to the regional chamber of architects; the structure by a designer with structural and building qualifications who belongs to the chamber of civil engineers.
For the authority: the site development plan and the architectural and building design (three paper copies or an electronic version), a declaration of the right to use the property, a planning decision (WZ) if one is required, and the declaration under Article 102a.
To be prepared beforehand: a surveyor's map for design purposes, geotechnical investigations and connection conditions for utilities.
Before work starts: the technical design, a qualified site manager and the construction log (paper or electronic).

Step by step: from plot to moving in

Checking the plot: the local zoning plan or the general plan and the infill development area, the slope of the land, the soil and the groundwater.
An application for planning conditions if there is no local zoning plan (to the commune head, mayor or city president).
The map for design purposes, geotechnical investigations and utility connection conditions.
The building design with a declaration that the existing technical requirements apply.
A notification (21 days for an objection) or an application for a building permit (up to 65 days) at the district authority.
The technical design, the site manager, the construction log and notice to the building inspectorate of the start date of the works.
Construction, with setting out and an as-built survey carried out by a surveyor.
The energy performance certificate and the acceptance records for the installations and connections.
Notice of completion to the district building inspector; after 14 days without an objection you can move in. An occupancy permit is only needed if you move in before all the works are finished.

How Talpa House works with you

Talpa House (Pribila spol. s r.o., Slovakia) has been designing and building family houses set into the ground since 2010, in monolithic watertight concrete with a green roof. We have built more than 21 houses in Slovakia, the Czech Republic and Hungary; we have not built in Poland yet and we are looking for local partners here. Light comes in through the glazed façade and rooflights, which keeps rooms 6–8 m deep bright.

The turnkey package covers the design and support through the procedure. The Polish building design is signed by an architect and a structural engineer with Polish qualifications whom we work with. For an indication of cost, use the calculator, and for the detail see the guide to underground house prices. You can see finished houses on our open days, and questions about a particular plot are best sent through contact.

Frequently asked questions

Do you need a building permit for an underground house?

Not always. A detached single-family house whose impact does not extend beyond the plot can be built on a notification with a design. A permit is needed when the impact reaches neighbouring plots or when the design calls for a departure from the regulations.

Will an underground house be granted planning conditions?

Yes, if the plot meets the conditions, and from 1 September 2026 also lies within an infill development area in the general plan. The decision may, however, dictate the shape of the roof, so it is worth showing the authority your concept early on.

Can you build a house into a slope?

Yes, and this is the simplest case: the façade is open on the downhill side, the ground in front of the windows sits at floor level and the rest of the house is tucked into the slope.

Can a bedroom be below ground level?

Not if there is no ground at floor level in front of it. Bedrooms and living rooms are planned along the open façade, with ancillary rooms underground.

Is sanitary inspectorate approval required?

There is no such route for a dwelling: the sanitary inspector's approval under Section 73(2) applies to commercial and industrial premises. Rooms have to meet the requirements for floor level and daylight. The only remaining option is a departure from the regulations (Article 9 of the Building Law), which requires ministerial authorisation and is an exception.

Sources

This is general information, not legal advice. Rules and practice vary between municipalities and district authorities; information current as of 29 October 2026.