What § 20 of the Building Code says
The obligation of owner's supervision rests on the owner, not on the contractor. The Building Code (ehitusseadustik, EhS) uses the public-law concept of omanik (the owner); this is usually the same person who is the client in the construction contract within the meaning of the Law of Obligations Act. The four subsections of § 20 frame the obligation.
Subsection 1 lays down the obligation. “The owner is obliged to ensure competent supervision over the construction of the building (hereinafter owner's supervision).” (unofficial translation). The list of the owner's obligations in § 19(1) point 5 repeats the idea: the owner ensures “owner's supervision in the cases provided by law”.
Subsection 2 requires independence. “The person carrying out owner's supervision may not, in the course of their economic activity, be connected with other activities relating to the same building or be connected with the persons whose activities they supervise.” The supervisor may therefore not be connected with the töövõtja (the contractor) or with the other persons whose work they check.
Subsection 3 allows a competent person to be brought in. If the owner lacks the competence themselves, they bring in a competent person, who acts under the responsibility of whoever brought them in.
Subsection 4 protects the client's claims against the contractor. “Carrying out owner's supervision does not exclude or limit the contractor's liability under the contract for work.” Where there is a defect, the contractor cannot argue that supervision should have found it and that the client has therefore lost their claim. Defects and the cost of repairing them are covered in the article on defects, repair and fundamental breach.
The current wording of subsections 1 and 2 has been in force since 1 August 2026. This article does not compare it with the earlier wording; what changed in the Building Code on 1 August 2026 is covered in the guide to the Building Code amendments.
The supervisor is also subject to qualification and notification requirements. Under Building Code § 24(2) point 3, carrying out owner's supervision requires a certified qualification, and under § 25 the activity must be notified. Under § 43(2), the notice of commencement of construction contains the supervisor's details. For the construction of a road that requires a building permit, § 98 requires owner's supervision separately.
When regulation no 80 applies
Regulation no 80, “Procedure for carrying out owner's supervision”, has been in force unchanged since 6 July 2015. It sets the minimum requirements for competent supervision (§ 1(1)) and was issued on the basis of Building Code § 20(5).
Its scope is defined by five cases (§ 1(2)): construction that requires a building permit; construction that requires a building notice, where a building design is needed under Annex 1 of the Building Code; construction for which a building design is needed to obtain an occupancy permit; construction that requires a notice of use, where a building design is needed under Annex 2; and substantial reconstruction. Subsection 3 excludes ancillary buildings without an indoor climate with a footprint of up to 60 m² and a height of up to 5 m.
Supervision lasts at least until the notice of use or the occupancy permit (§ 2(1)). A supervision contract that ends earlier does not meet the regulation's minimum requirement, so it is worth writing that end point into the contract.
Mandatory checks and deadlines
The regulation lists 13 checks (§ 4(2)). Three of them matter for the final cost: point 5 requires checking whether construction conforms to the design and to “the terms and quality agreed in the contract between the builder and the owner”; point 10 covers covered works; point 13 requires checking “the quality of construction and its conformity with the construction contract”. Supervision therefore checks whether what was agreed in the contract is being done. That is not the same as checking whether the sum claimed for the work is correct.
| Obligation | Provision | What it gives the client |
|---|---|---|
| Supervision programme or quality assurance plan, prepared together with the owner | § 4(1) | the chance to add the checkpoints the client needs to the plan |
| 13 mandatory checks, including conformity with the construction contract | § 4(2) points 5, 10, 13 | evidence that the work conforms to the terms and quality of the contract |
| Immediate notification (12 cases, including non-conformity with the design) | § 5(1) | early warning that allows a decision before the work is covered |
| Written notice of other breaches of the owner's rights within 2 working days | § 5(2) | a written trail that can later be used as evidence |
| Notices entered in the construction works diary | § 5(4) | a document that is kept anyway under Building Code § 15 where a building permit is required |
| Demands in writing within 2 working days | § 6(3) | a deadline whose breach can be established |
| Refusal to sign a document, with written reasons | § 6(4) | reasons, if supervision does not confirm a certificate or other document |
The supervisor's rights are aimed at conformity. Under § 6(1), they may require, among other things, that the building design be brought into conformity, that documents be provided, that construction products be replaced, that works not conforming to the design or the contract be redone, and that works be suspended in the event of danger or non-conformity. These rights protect quality, but indirectly also the price: non-conforming work found before it is covered is cheaper to repair than afterwards. How the documents later work as evidence is covered in the article on construction records as evidence.
The regulation provides for checking deadlines and proposing termination of the contract only for roads (§ 6(5)). For other buildings and structures, this is not part of the minimum content of supervision.
The client must give the supervisor the necessary documents. Under § 3(2), the owner gives the supervisor at least the building permit and the building design, the contract between the builder and the owner, surveys, expert assessments and opinions. A supervisor who is not given the construction contract cannot check conformity with it.
What supervision does not have to do
Supervision does not assess whether the design solution is suitable. Under § 4(6): “The task of the person carrying out owner's supervision is not to assess the suitability of the architectural or technical solution presented in the building design”. They may propose changes, but design errors are a matter for the liability of the projekteerija (the designer), as explained in the article on the designer's liability.
The regulation does not mention the price, the invoices submitted for the works or additional works. The wording matters: the regulation does not provide for it, which does not mean it is prohibited. The supervisor may carry out cost control if the contract requires it. If the contract does not require it, the client cannot assume the check was done.
| Task | In the minimum content of regulation no 80 | If the client wants it, it must be written into |
|---|---|---|
| Conformity with the design and the construction contract | yes (§ 4(2) points 5 and 13) | nothing to add, though the plan may specify it |
| Checking covered works | yes (§ 4(2) point 10) | nothing to add |
| Checking the quantity of work done and the sum claimed for it | not mentioned | the supervision contract |
| Distinguishing lisatöö (additional work) from muudatustöö (changed work) and assessing the quotation | not mentioned | the supervision contract or the project manager's contract |
| Checking deadlines (except roads) | not mentioned | the supervision contract or the project manager's contract |
| Assessing the suitability of the design solution | excluded (§ 4(6)) | the designer's contract or an expert assessment |
What the client adds to the supervision contract
If cost control is needed, it is written as a task, not as a general duty of care. A clause stating that “the supervisor protects the client's interests” does not say whether they check the sums claimed for the works. A clear contract term says three things: what is checked (the quantity of work done, the sum for one payment period, quotations for changes), against what (the construction contract and its annexes) and within what time after receiving the document.
For additional works, an opinion is often enough, rather than a decision. The supervisor can give a written opinion on whether the requested work falls within the subject matter of the contract, but the decision is the client's. If the client wants someone else to be able to approve changes on their behalf, that goes into the authority of the projektijuht (the project manager) or tellija esindaja (the client's representative), covered in the article on the project manager and the client's representative.
Where there are several supervisors, the split is in writing. Under § 2(2), the owner defines each one's field and scope in writing and informs the builder. If cost control is given to one of them, that must be unambiguous from the same document.
Independence must be confirmed in writing. Under § 2(3) and (4), the supervisor confirms their independence in writing and reports circumstances that could affect it. Subsection 5 requires a responsible competent person to be appointed. The client keeps these confirmations with the contract.
The supervision programme is where the client's needs become checkpoints. Under § 4(1), the supervision programme or quality assurance plan is prepared together with the owner. The client can add the moments that affect the final cost most: inspection of covered works before the next stage begins, a written record of every change in the diary, and an interim report before each payment. The programme does not replace the contract, but it shows whether the tasks agreed in the contract are actually in the schedule. If the programme contains no cost-related checkpoint, there probably is none in practice either.
No prices are given. There is no neutral public source for the price of this service, so the article does not give price levels. If the project is a renovation, a separate guide covers choosing the designer and supervision for a renovation.
This article describes the legal rules as at the date of checking and is intended for professional orientation. It does not replace legal advice or a review of the specific case.