Three regimes, not two
The question „do I only need a notification, or a full permit?“ actually has three answers, not two. Since 1 April 2025 Slovakia has been governed by a new building act, no. 25/2025 Coll., which together with the spatial planning act no. 200/2022 Coll. replaced the 1976 legislation. It sorts construction work into three bands: fully exempt structures (you submit nothing), a minor structure notification, and full building intent proceedings resulting in a building intent decision. That last one replaced the old pairing of zoning decision plus building permit, so „building permit“ is now colloquial shorthand for something that formally goes by a different name.
The practical consequence is simple: before you commission any design work, you need to know which of the three bands your structure falls into. Size alone does not decide it. What also matters is whether the structure is single-storey, how far it stands from the plot boundary, what it will be used for and where it stands. The same shed can be fully exempt in one situation and require full proceedings in another.
| Regime | Typical example | What you submit | Authority's deadline |
|---|---|---|---|
| No notification | Garden shed up to 25 m², at least 2 m from the boundary | Nothing | None |
| Minor structure notification | Garage, workshop or carport up to 50 m² and 5 m tall | Notification plus documentation to the building office | 30 days to verify |
| Building intent proceedings | Family house, extension, change of use | Application and building intent design | Weeks to months |
What counts as a minor structure
Under the new act a minor structure is a single-storey building permanently attached to the ground that does not materially affect its surroundings or the character of the area. An above-ground minor structure is capped at 50 m² of built-up area and 5 m in height; an underground one at 25 m² and 3 m in depth. The old act allowed only 25 m², so the threshold doubled. A single garage, a workshop or a larger shed that once needed a full permit can now go through a notification.
The band below is simpler still. A structure up to 25 m² standing at least two metres from the plot boundary, in a location that is not protected or otherwise sensitive, needs no notification at all. Those two metres are a condition, not a recommendation: the same shed one metre from the fence drops back into the notification regime.
| Category | Area limit | Height or depth limit | Procedure |
|---|---|---|---|
| Exempt structure | up to 25 m² | up to 5 m | Nothing is filed, provided it is at least 2 m from the boundary |
| Above-ground minor structure | up to 50 m² | up to 5 m | Notification, 30-day verification by the authority |
| Underground minor structure (cellar, cesspit, pool) | up to 25 m² | up to 3 m deep | Notification |
| Structure above the minor-structure limits | over 50 m² | over 5 m | Building intent proceedings |
| Minor structure under act 50/1976 (until 31 March 2025) | up to 25 m² | usually 5 m | Historical threshold, no longer used for new filings |
Watch out for one trap: not every structure under 50 m² is a minor structure. Function matters too. A habitable cabin of 45 m² may be classed as a „simple structure“, meaning something a notification will not carry, even though it sits comfortably inside the area limit. The notification route is meant for ancillary and utility buildings, not for space intended for permanent living.
What you file, and with whom
You file the notification with the locally competent building office, these days usually electronically through the URBION information system, or on paper. It is not an application asking for something; it is a notice the authority verifies. Once it is verified, or if the authority stays silent through the deadline, you may build. Competence follows the location of the plot, not your place of residence, which catches out more than a few owners of holiday cabins and recreational land.
Section 63 of act 25/2025 Coll. sets out what the notification must contain. In practice that means five groups of documents:
- the builder's identification details and contact information,
- proof of ownership of the plot or another right to it, meaning a land registry extract,
- details of the location and type of structure, including a site plan with parcel numbers,
- design documentation detailed enough to verify what is being built, where and how (plan, section, elevations, structural solution, materials),
- binding opinions from the relevant authorities and utility operators where these are required.
The documentation is far lighter than building permit documentation, but it is not a sketch on graph paper. It has to be legible to an official who has never seen the plot, and it has to match what you actually build, because it is the yardstick against which the finished structure is later judged.
What happens after you file
The authority has 30 days from delivery of a complete notification to verify it. If within that period it neither issues the verification nor rejects the notification, deemed consent kicks in: the verification is treated as granted. This is one of the act's headline changes, and it is aimed at silent authorities, not at the rules themselves.
It is worth being precise here, because this is where most of the misunderstanding lives. Deemed consent does not protect you from a substantive error. If the structure conflicts with the land-use plan, a protection zone or a technical standard, the authority's silence changes nothing and the risk sits with you. Deemed consent cures delay, not non-compliance. The clock also only starts on delivery of a complete filing, so an incomplete notification never starts it at all. That is the single most common reason the promised thirty days stretches into two months.
If the authority objects, it has three routes. It can call on you to supplement the file, which suspends the deadline. It can reject the notification with reasons, and that is a decision you can appeal. Or it can conclude that the structure does not meet the minor-structure conditions and must go through building intent proceedings. That last outcome is the painful one, because it means fresh documentation, fresh opinions and a fresh schedule.
Building without the right consent
An unauthorised structure is not merely an administrative nuisance. The authority can halt the work, fine the builder and, in the worst case, order the structure removed. The more practical consequences arrive later: without proper consent the structure will not pass occupancy approval, will not receive a house number and will not be entered in the land registry. On sale, a buyer and their bank will read it as a liability rather than added value, and an insurer facing a claim on an unauthorised structure has a strong argument for reducing the payout.
Retrospective legalisation does exist, but the new act tightened it. In short: older unauthorised structures can be dealt with under a transitional regime following the previous rules, and only up to a statutory cut-off date, while structures put up without consent after the new act took effect have a considerably narrower path to legalisation. The transitional provisions were still being refined by amendments through 2025 and 2026, so verify the exact date and scope directly with the building office or in the current wording of the act. I would rather not print a date here than print one that is wrong in six months.
Retrospective approval is more expensive than the original notification in every case. You need a survey of the as-built condition, documentation prepared after the fact, opinions you would otherwise have collected in advance, and proof of compliance with the land-use plan. If the structure is not compliant, legalisation is not available and removal is the only route left. Three extra days spent getting the notification right is a far cheaper bill paid in advance.
The same logic applies to structures you inherited or bought. If the land registry shows an object that the house documentation never mentions, deal with it before you try to attach anything new to it. A notification for an extension to a structure that was never itself legalised will be refused, and you will learn about the problem at the least convenient moment.
Where the line is genuinely unclear
Most writing on this subject pretends the decision is mechanical: measure the area, check it against a table, done. In practice it is not. These are the places where even an experienced designer will not answer without a phone call to the authority.
- Built-up area versus usable area. An overhanging roof, a covered terrace or a carport may or may not count towards built-up area. The difference between 48 and 52 m² decides the entire regime.
- Extension versus free-standing structure. If the new construction touches the existing house, it is generally no longer a minor structure but an alteration of an existing building, and that will not pass through a notification.
- Alterations inside the house. Replacing finishes is ordinary maintenance. Cutting into load-bearing structure, or a layout change with fire-safety consequences, is a different story.
- Pool, cesspit, retaining wall, fence. Underground and civil-engineering objects carry their own limits and often their own consulted authorities.
- Where the plot sits. In a heritage zone, inside a utility protection zone or on a flood plain, the exemptions narrow regardless of the size of the structure.
In these cases the cheapest tool you own is a fifteen-minute phone call, or a short visit to the building office, before anyone starts drawing. Bring a site plan, state the dimensions, the setbacks and the intended use, and ask outright which regime they consider it to fall under. Municipalities keep their own lists of accepted minor-structure types and have their own practice, none of which you can read out of the statute. An official's answer does not bind anyone the way a decision does, but it saves you the most expensive mistake in the whole process: a design prepared for the wrong regime.
In summary
A notification is a fast route, not a shortcut around the rules. It works for single-storey ancillary structures inside limits the act states clearly, and it rewards whoever files a complete, accurate submission first time. Building intent proceedings are heavier going, but they handle what a notification cannot. The worst option is the third one: build first and ask afterwards. If you do not know which category you are in, find out before you commission the design. It is the only stage at which that information costs nothing but a phone call.