Three people move around a house build in Slovakia and clients confuse them constantly: the stavebný dozor (construction supervisor), the stavbyvedúci (site manager) and the architect acting as author supervision. The difference is not academic. It decides who pays whom, who is answerable for what, and who you call when something goes wrong on site. The most expensive version of the mix-up looks like this: the client believes there is supervision on site because the contractor put somebody there. That somebody is the site manager, the contractor's own person, and protecting the client is not his job. This piece is the detail behind the overall process of building a house in Slovakia.
Three roles that are not interchangeable
Construction supervision is carried out by a professional hired and paid by the client. The supervisor represents the client's interests and verifies that the work follows the approved documentation, technical standards and safety rules. It is the only one of the three roles that is on site purely for the client.
The site manager is the contractor's person. The construction company appoints and pays him. He organises the work, coordinates the trades, is answerable for site safety and keeps the electronic construction diary. It is a competent and legally required function, but it represents the other side of the works contract. Under act 25/2025 Z. z. on construction, every build carried out by a contractor must have a site manager, and on designated structures he must be an authorised site manager.
Author supervision is performed by the original architect or designer, the author of the documentation. Nobody else can do it, not even an equally qualified colleague, because it is the author's right to his own work. It tracks whether what was designed is what is being built: materials, finishes, details, proportions, and it assesses the substitutions the contractor proposes during construction.
| Role | Answerable for | Who pays | When it is needed |
|---|---|---|---|
| Construction supervision | Compliance of the work with the documentation, standards and permit conditions; checking materials before they are built in; independent entries recording findings and defects | The client | Mandatory on designated and larger structures; on an ordinary family house it is the client's own decision |
| Site manager | Organising and directing the work, coordinating trades, occupational safety, keeping the construction diary | The contractor, inside the contract price | Always, when a contractor carries out the build; on designated structures he must be authorised |
| Author supervision | Faithful execution of the design intent, approving or rejecting changes of material and detail | The client, under a contract with the architect | Not mandated by law for every build; the architect as author has the right to ask for it |
What supervision does not do
The list of things you cannot expect from supervision matters as much as the list of duties, because clients expect them anyway.
Construction supervision does not run the site. It does not allocate work, set the sequence, chase subcontractors or answer for the programme. That is the site manager's job. Nor is the supervisor permanently present: he inspects at agreed intervals and before critical stages, not eight hours a day. And he does not guarantee that the price will not rise. He guarantees that the execution matches the documentation.
Author supervision is not a technical inspection of the whole build. On site the architect deals with whether the specified material and the specified solution are the ones being used, and whether the detail is right. Verifying concrete strength classes, electrical test certificates or pressure tests on services is not his role. If you want systematic technical checking, you need construction supervision, not author supervision.
Neither form of supervision replaces the works contract. If the contract does not define scope, quality and how work is handed over and accepted, the supervisor has nothing to base an objection on. Supervision enforces a contract, it does not substitute for one.
And none of these roles is insurance against choosing the wrong contractor. Supervision can find a fault and document it, but it cannot turn a poor firm into a good one. If the contractor is picked on lowest price alone, the supervisor ends up recording problems instead of preventing them.
When each role is compulsory
Act 25/2025 Z. z. on construction has applied since 1 April 2025 and, together with act 200/2022 Z. z. on spatial planning, it replaced the original building act of 1976. For supervision the rule that follows is fairly simple. A site manager is compulsory whenever a contractor carries out the build. Construction supervision is compulsory on designated and larger structures, meaning buildings that are technically more complex or carry more risk. For an ordinary family house the law does not impose it across the board.
So on most family houses construction supervision is the client's decision rather than an obligation. Author supervision is likewise not imposed on every build, but the law grants the author of an architectural work the right to request it and obliges the client to allow it, unless that would conflict with the client's legitimate interests.
Self-managed construction is a special case. If you run the build yourself without a contractor there is no site manager, and the construction supervisor becomes the only professional systematically checking quality and keeping records. In that arrangement supervision is not a luxury but effectively a precondition for getting through occupancy approval without complications.
How supervision is paid for
There is no binding fee scale in Slovakia for any of these services. Any figure of the form "supervision costs this much" should therefore be read as a parameter of one specific offer, not as a rate. Asking about the structure is more useful than asking about the number: what exactly am I paying for, how often does it happen, and what sits outside the fee.
| Role | Usual basis of charge | What the amount depends on | What to agree in advance |
|---|---|---|---|
| Construction supervision | Hourly rate, a rate per site visit, or on larger projects a percentage of the construction budget | Size and complexity of the build, region, travel distance, agreed frequency of inspections | Minimum visits per month, compulsory inspections before elements are covered up, the form of reporting to the client |
| Site manager | Part of the contract price, never invoiced to the client separately | Not a separate line in the client's budget | That he is named in the works contract and is not swapped without notice |
| Author supervision | Hourly rate or a fixed sum per stage, normally outside the base design fee | Complexity of the details, number of agreed visits, distance to site | Which stages supervision covers and how extra work caused by changes is handled |
With an architect, author supervision is almost always a line outside the base design fee and is invoiced as the build proceeds, usually monthly or per visit. For construction supervision the commonest models are an hourly rate or a rate per visit, with the percentage model appearing mainly on larger budgets. The amount depends on project size and region enough that comparing two offers is only meaningful when both describe the same number of visits and the same scope of activity.
The construction diary and what a client should see in it
Since April 2025 the construction diary is kept primarily in electronic form. The site manager keeps it, but it is not his private document. The construction supervisor, the designer performing author supervision and the client all have the right to make entries. That makes the diary the best monitoring instrument a client has during a build, and also the one most often left unused.
What you should see in it regularly:
- daily records of work carried out, not a weekly summary;
- materials and products delivered, with specifications, so it can be checked later against the design;
- records of elements inspected before being covered up, ideally with photographs;
- the construction supervisor's own entries, not only the contractor's;
- recorded deviations from the design, naming who approved each one;
- results of tests, measurements and inspections.
If a whole month passes without a single supervisor entry, supervision was not really happening on site. This is a check a client can run alone in ten minutes, and it surfaces problems far earlier than the occupancy proceedings do.
What happens when supervision is cut to save money
Cutting supervision is the most understandable and the least recoverable saving a client makes during a build. The reason is simple: the faults supervision catches are almost always the faults that get covered up immediately afterwards.
The typical sequence runs like this. The waterproofing below ground goes in unchecked, gets backfilled, and the problem shows up two years later as a damp living-room wall. Or the insulation is swapped for a cheaper one with different parameters, nobody notices, and the house ends up with higher bills and an energy certificate that does not match. Or the detailed design gets simplified on site because "this is how it is normally done", and the detail meant to deal with a thermal bridge quietly disappears. The cost of putting it right after it is covered is always a multiple of the supervision fee that would have caught it.
The second payment for missing supervision comes at claim time. Without supervisor entries in the diary the client argues from a weak position: there is no record of when the problem appeared, who flagged it and what was done about it. The contractor then attributes the damp wall to how the house is used, and the client has nothing to answer with. Photographs in the diary are cheaper than any expert report later commissioned to stand in for them.
When the contractor recommends the supervisor
Be particularly careful when the construction supervisor is recommended, arranged or even paid for by the contractor. It sounds practical and saves you the search. It is a direct conflict of interest: that supervisor is meant to check the very party that brought him the work and will bring him more. There need be no bad intent, it is enough that an awkward diary entry is much harder to write inside that relationship.
The rule I give clients is short: you choose and pay the construction supervisor yourself, you choose him before signing the works contract, and he should have no personal or commercial link to the contractor. If the contractor proposes that arrangement on his own initiative, that is information in itself.
Three people, three loyalties. The site manager belongs to the contractor, construction supervision and author supervision belong to you. Lose one of them and nobody else picks up the role. It simply stops being done.