“We will move the house by a metre”, “raise the roof a little”, “the contractor suggests another solution”. During construction, the original design often encounters new needs and conditions on the plot. Problems arise when a change is made before its legal consequences are checked.
The client's and contractor's agreement is not enough to make every change lawful. It is necessary to establish what the departure concerns, whether it is material and what formalities must be completed before the work is carried out.
The key question is: is the change merely planned, or has it already been made? The answer determines the appropriate procedure.
Who assesses whether a departure from the design is material?
The designer classifies the proposed departure. If it is considered non-material, the designer adds the appropriate information — a drawing and description — to the construction documentation.
If the departure is material, a decision amending the building permit must be obtained before it is implemented.
An entry in the construction log alone does not replace the required decision. Do not rely solely on a contractor's verbal assurance that “it will all be sorted out at completion”. The designer's assessment should address the specific solution and be reflected in the documentation. It does not prevent the competent authority from reviewing whether the classification is correct.
What changes may constitute a material departure?
Increasing the building footprint by more than 5%
Examples include extending the building or enlarging its outline beyond the statutory threshold. The relevant measure is the building footprint, rather than the usable floor area of rooms.
Changing the height, length or width by more than 2%
This may involve raising the house, extending a wall or increasing the building's width. For example, a 20 cm change to a planned height of 8 m exceeds 2%. The designer should nevertheless check the method of measurement and extent of the departure.
Remaining within a statutory threshold does not automatically make a change non-material. The other criteria must also be examined.
Changing the number of storeys
Examples include adding a floor or basement not included in the approved design. For attic changes, check whether the number of storeys actually changes. Calling a space an “attic” or “loft” does not decide the issue.
Changing the location so that the area of impact extends further beyond the plot
Moving a house or making other site-layout changes may be material if they extend the building's area of impact beyond the plot on which it was designed. Not every relocation is automatically a material departure. Distances from boundaries, building lines and other requirements must nevertheless also be checked.
Changing the intended use
An example might be converting a residential part into a workshop or business premises, if this actually changes the intended use. Simply placing a desk for remote work does not by itself establish such a change.
A change affecting the local spatial plan or development conditions
Problematic changes may include altering roof geometry, exceeding the permitted height, breaching the building line or failing to maintain the required biologically active area. A replacement design does not override planning restrictions. Not every proposed change can be approved.
Changing accessibility conditions
This concerns departures affecting the conditions needed for people with disabilities, including older people, to use the building. Removing a planned ramp or lift may be an example if it affects compliance with accessibility requirements.
A change requiring new decisions or approvals
A departure requiring a new or amended decision, permit, approval or notification required for the development may be material. The Act provides exceptions, including certain changes approved in terms of fire safety or by the competent heritage conservation authority.
Replacing a specified heat source with a solid-fuel source
A material-departure criterion is replacing a heating or hot-water source powered by liquid fuel, gas, renewable energy or a district-heating network with a solid-fuel source. Replacing a planned heat pump with a solid-fuel boiler is an example. This does not mean every replacement heating appliance falls into this category.
A change may meet several criteria at once. Raising a roof can affect the house's height, number of storeys and compliance with the local plan. Article 36a of the Polish Building Law
Does a structural change always require an amended permit?
Not every technical change is a material departure from the approved plot-development or architectural and construction design. That does not mean unrestricted discretion.
A departure from the technical design requires the designer to make the changes beforehand and have them checked where required. If the solutions were subject to approvals, the relevant approvals must be obtained again.
This applies, for example, to a proposed change in the floor structure or structural solution. First establish whether it affects only the technical design or also the approved solutions and permit conditions. Article 36b of the Polish Building Law
A change is planned: what steps should be taken?
The first step is to give the designer a description of the proposed solution, including its scope, reason and anticipated effect on other elements of the development.
If the change is non-material, it must be properly recorded by a drawing and description and, where necessary, the technical design updated.
If it is material, prepare documentation incorporating the new solutions and apply to amend the building permit.
Which authority receives the application?
The developer or their representative applies to the competent architectural and construction administration authority:
- usually the head of the county (starosta), through the architecture and construction department;
- in a city with county status, the city mayor;
- in cases specified by law, the voivode, the regional government representative.
For a typical house built within a county, the county office will be competent.
What documents should be prepared?
Depending on the scope of the change, the main documents are:
- an application identifying the developer and existing permit;
- the plot or site-development design and architectural and construction design incorporating the changes to the required extent;
- a declaration of the right to use the property for construction purposes;
- a decision on development conditions, where required;
- the relevant opinions, approvals, permits and other required attachments;
- a power of attorney if a representative is appointed;
- proof of stamp duty payment where payable.
For older permits, transitional provisions and the appropriate documentation requirements must also be checked.
The application may be filed on paper or electronically under the applicable procedure. Neither filing the application nor preparing a replacement design authorises a material departure. The decision must be obtained and confirmed to be enforceable. General Office of Building Control (GUNB): amending a building permit
The change has already been made: what now?
First establish the actual discrepancies. A designer's analysis, surveying measurements or an as-built survey may be needed. Until the position is clarified, avoid further work that deepens the non-compliance.
If the departure is non-material, it must be properly reflected in the documentation and checked for compliance with the law.
If a material departure was made without the required decision, do not assume that a later ordinary permit-amendment application will resolve the problem. As a rule, the building supervision authority must act — usually the county building supervision inspector (PINB). Where regional jurisdiction applies, the regional inspector (WINB) is competent.
What should be prepared for building supervision?
Gather:
- the building permit and later decisions;
- the approved designs;
- the current technical design;
- the construction log;
- a description of the changes, their dates and the stage of work;
- photographs, measurements or an as-built survey;
- the designer's assessment and any technical opinions.
If the developer informs the authority of an irregularity, the letter should identify the property, development, permit and work carried out.
There is no universal set of documents whose submission automatically regularises a departure. Supervision proceedings are initiated by the authority of its own motion, and it determines further obligations.
What can the authority require?
In proceedings concerning a material departure, the authority may require a replacement plot-development or architectural and construction design reflecting the work carried out.
It may also order steps or work needed to bring the development into compliance. Once the obligations are fulfilled, it reviews the documentation and issues the appropriate decision on design approval and, if construction is ongoing, permission to resume work.
Not every change can be retained. In specified cases, restoration of the previous condition or demolition of the building or part of it may be ordered. Articles 50–51 of the Polish Building Law
What is the “yellow card” procedure?
In specified cases, the authority may warn the developer of the need to bring the work into compliance with the permit, design or legislation.
After 60 days from the warning, or earlier at the developer's request, the authority checks compliance. If discrepancies remain, the supervision-proceedings rules apply.
A warning does not permit the change to remain or provide a general exemption from liability. Its purpose is to bring the work into legal compliance. Article 51a of the Polish Building Law
What penalties may apply to departures from the design?
A fine for a petty offence
Carrying out work in the manner described in Article 93 point 6 of the Building Law, including materially departing from the approved design, may constitute a petty offence.
A court-imposed fine generally ranges from PLN 20 to PLN 5,000. This range should not be confused with an on-the-spot penalty notice. Liability requires identifying the offender and establishing the elements of the offence. Article 24 of the Polish Petty Offences Code
A penalty during a mandatory inspection
If irregularities are identified within the statutory scope of a mandatory inspection connected with an occupancy permit, a penalty under Article 59f of the Building Law may be imposed.
It is calculated as: PLN 500 × building-category coefficient × building-size coefficient.
For a single-family residential building, the coefficients are 2 and 1, giving PLN 1,000 for each irregularity subject to this sanction. Individual penalties are added together.
This is not a general penalty for any material departure from the design. The amount applies only where Article 59f is used after irregularities are identified within the statutory scope of a mandatory inspection. It does not mean every departure in a single-family house can be resolved by paying PLN 1,000.
Independently of penalties, the developer may incur costs for a replacement design, expert reports, measurements and remedial work. Occupying a building without the required formalities may have separate consequences. Articles 59f–59i of the Polish Building Law
The legalisation fee: when is it actually payable?
Approval of a replacement design in remedial proceedings under Article 51 of the Building Law does not itself trigger the legalisation fee under Article 49d.
A material departure in a development carried out under a permit must be distinguished from constructing a building or part of one without the required permit or notification, or despite an objection.
If the work actually amounts to constructing a new building or part without the necessary authorisation, legalisation proceedings may apply. Calling the documentation a “replacement design” does not determine the procedure.
How much does legalising a single-family house cost?
In the ordinary legalisation procedure for construction requiring a permit and specified construction requiring notification, the fee is calculated as follows:
PLN 500 × 50 × building-category coefficient × building-size coefficient.
For a single-family residential building: PLN 500 × 50 × 2 × 1 = PLN 50,000.
The PLN 50,000 amount concerns a particular building classification and the ordinary legalisation procedure. It is not a universal fee for every irregularity or every change requiring a replacement design.
For other building categories, the amount can be much higher. The Act also provides fixed fees of PLN 2,500 or PLN 5,000 for specified types of construction and installation.
Does payment guarantee legalisation?
No. The required documents must also be submitted and the legalisation conditions met. It is not possible to “buy” the right to retain any building constructed.
In ordinary proceedings, the authority issues an order suspending construction, even if construction is complete. It informs the party of the legalisation option and fee.
An application for legalisation may be filed within 30 days of service of the order. If an interlocutory appeal is lodged, the period runs from the date the order becomes final in the administrative process.
After the application, the authority requires the legalisation documents. Once these are checked and deficiencies remedied, it sets the fee by an order that may be challenged by interlocutory appeal.
When must payment be made, and are instalments available?
As a rule, the fee must be paid within seven days of service of the order setting its amount.
An application may be made to the competent voivode for deferral, instalments or full or partial remission under the appropriately applied provisions of the Polish Tax Ordinance.
The application should identify the relief requested and supporting circumstances. Documents on income, assets, living expenses and liabilities may help. Relief is not automatic.
Submitting an application for relief under Article 67a § 1 of the Tax Ordinance suspends legalisation proceedings under the rules in Article 49c of the Building Law.
What happens if the fee is not paid?
Failure to pay on time is a statutory ground for ordering demolition of the building or part of it.
Such a decision may also follow from failure to apply for legalisation, submit documents or remedy their deficiencies, or from continuing construction despite its suspension.
Payment of a fine or other penalty does not replace the legalisation fee or the decisions required to retain the building. Articles 48–49e of the Polish Building Law
Is legalisation without a fee possible?
The simplified legalisation procedure does not impose the fee applicable to ordinary proceedings. Documentation costs remain, particularly those of an as-built surveying inventory and a technical expert report.
For construction without a permit or notification, the basic threshold for simplified proceedings is at least 20 years since completion, subject to statutory restrictions.
Separate provisions address material departures from the permit or approved design where at least 10 years have passed since the work was completed. These refer to appropriate application of the simplified procedure.
The passage of time does not itself legalise a building. The correct procedure must still be established and documentation and safety requirements met. Articles 49f–49i and Article 50(6) of the Polish Building Law
Why should you not wait until construction is finished?
Discrepancies discovered at completion may delay lawful occupation. A decision may be missing, the documents may not reflect the work or costly corrections may be needed.
Before making a change, agree its scope with the designer, check the formalities and arrange the work schedule accordingly. If the change has already been made, assess the actual condition and choose the appropriate procedure rather than assuming that later amendments to the drawings will suffice.
Legal basis: in particular Articles 35, 36a–36b, 48–49i, 50–51a, 57, 59f–59i and 93–94 of the Polish Building Law, and Article 24 of the Polish Petty Offences Code.
Law as at 18 October 2026.
Barbara Kardynia, Advocate
Barbara Kardynia Law Office
Telephone: +48 795 674 344
Email: b_kardynia@icloud.com
Website: adwokatkardynia.pl