The design is the basis of the price
Regulation no 97 links the level of detail of the design directly to the price. Under § 9(1), the põhiprojekt (the main design) describes the solutions and quality “with a level of detail that makes it possible to determine the budgeted cost of the building, organise the construction procurement and prepare a quotation for construction” (unofficial translation). A quotation given on the basis of the main design is therefore only as good as the design it was prepared from.
The stages are binding briefs for one another. Section 5(1) of the regulation names three stages: the eelprojekt (preliminary design), the main design and the tööprojekt (working design). Under subsection 2, the solutions are submitted to the client for approval, and under subsection 3 the approved previous stage becomes the “binding brief” for the next stage. For the client, approval is therefore a decision, not a formality: what they approve in the preliminary design is what the main design develops further.
Economy belongs in the preliminary design. Under § 8(3) of the regulation, the preliminary design analyses the suitability and the “economy” of the solutions. The economic choice is therefore made as early as the preliminary design, before the main design makes it possible to determine the budgeted cost. How the accuracy of an estimate changes with the design stage is covered in the guide to estimate accuracy by design stage; it is not repeated here.
The working design provides the level of detail needed for construction (§ 10(1) and (3)). If the contract is signed on the basis of the main design and the working design is prepared later by the contractor or someone else, the contract must state which document is the basis of the price and what happens if the working design brings in works that were not in the main design. What the contract price covers is explained in the article on the scope of the contract price.
What the law and the regulation require of the design
The design must make it possible to build a compliant building. Under § 13(1) and (2) of the Building Code (ehitusseadustik, EhS), the building design must make it possible to build a building that meets the requirements and to check its conformity; under subsection 3, the detailed requirements are in regulation no 97. Section 14 adds what must be taken into account in design and requires a construction survey where necessary.
The design must be free of contradictions. Under § 2(1) of regulation no 97, the design must be legible, free of contradictions, understandable and unambiguous to a specialist. If the documents nevertheless conflict, § 6(2) sets their order of priority; that rule and its effect on the price are covered in the article on conflicts between the drawings and the specification.
The peaprojekteerija (the lead designer) is responsible for the parts fitting together (§ 2(3) to (5)). Where several designers prepare the design, for example an architect and the designers of the specialist parts, the lead designer ensures that the design is complete and that its parts fit together. For the client, this is an important point of address: a clash between the architecture and the building services is not their problem to solve, but a defect in the design.
In some cases an expert assessment is mandatory. Under Building Code § 14(3), the building design must undergo an expert assessment, carried out by a competent person independent of the author of the design, if the building is technically complex or has a high hazard potential, or if the authority has a reasoned doubt. The expert assessment checks the design; the law does not say that it releases the designer from their contractual liability, and the allocation of liability arises from the contracts.
The designer must be competent. Under § 24(2) point 2, designing a building that requires a building permit calls for a certified qualification. Under § 21, the undertaking appoints a competent person responsible for the design and is responsible for the persons acting on its behalf (subs. 2). Under § 21(3), obligations under the Building Code do not affect contractual obligations, and where they conflict the Building Code obligation prevails.
Changes must be documented. Section 12 of the regulation deals with changes to the design that do not require a new building permit: if the design is changed by another author, the original author's opinion is sought (subs. 4); the explanatory memorandum to the changes sets out the reasons and possible effects (subs. 7); and a list of valid documents is drawn up, showing the documents added, replaced and invalidated (subs. 8). During construction, the list of valid documents is the client's best defence against the question of which version of the design the price was agreed on.
| Requirement | Provision | What it means for the final cost |
|---|---|---|
| The design makes it possible to build and to check | EhS § 13(1) and (2) | a design that does not allow this can create additional works |
| Free of contradictions and unambiguous | regulation no 97 § 2(1) | a contradiction can become an additional claim during construction |
| The lead designer ensures completeness | § 2(3) to (5) | a clash between parts is a defect in the design |
| An approved stage is a binding brief | § 5(3) | the client's approval fixes the framework of the next stage |
| Economy analysis in the preliminary design | § 8(3) | the economic choice is made early |
| The main design makes it possible to determine the budgeted cost | § 9(1) | the main design is the basis of the quotation |
| Expert assessment for complex buildings | EhS § 14(3) | independent checking before construction |
| Changes and the list of valid documents | regulation no 97 § 12(7) and (8) | evidence of which version the price was agreed on |
How a design error ends up on the client's bill
Towards the contractor, the client is responsible for the design. According to the Supreme Court's case-law review, the client is responsible for the conformity of the design they give the contractor (review p. 15, referring to Supreme Court civil chamber judgment of 19.12.2017, 2-15-15662/55, para 19). This is a trend of published decisions, not the wording of the law, but its logic is simple: the contractor priced and built what they were given.
The Law of Obligations Act supports the same result. Under § 641(3) of the Law of Obligations Act (võlaõigusseadus, VÕS), the contractor is not liable for a lack of conformity resulting from the client's instructions, defects in material supplied by the client or preliminary work by a third party, if they checked these sufficiently. A design supplied by the client can be such an instruction; the contractor's duty to check it sufficiently nevertheless remains, and its extent is often the central question in a dispute.
The chain therefore has two steps. In the first step, the client pays the contractor for work that was added or had to be redone because of the design error. In the second, they claim the cost from the designer, if the design contract allows it. Neither step happens automatically, and the second depends entirely on what the design contract says.
The contract price and the technical necessity of a work are not the same thing. According to the Supreme Court's case-law review, the mere fact that a work should have been in the tender or was technically necessary does not prove that it was included in the price (2-15-15662/55, para 13; Supreme Court civil chamber judgment of 20.09.2017, 2-13-40856/124, para 14). If the design omits a technically necessary work, there is a risk that the client pays for it separately, and the question shifts to the designer's liability.
What to write into the design contract
This article does not classify the type of design contract. Whether it is a töövõtuleping (contract for work) or a käsundusleping (contract of mandate) determines which provisions of the Law of Obligations Act apply. As this question is not resolved by the sources checked here, it is safer for the client to write the essential obligations into the contract expressly, rather than rely on the default rule of the law.
Write down what the designer is responsible for and by what standard. Are they responsible only for the technical compliance of the design, or also for the design matching the budgeted cost agreed with the client? If the budgeted cost is part of the brief, write down who calculates it, at what stage and what happens if the tenders obtained on the basis of the main design exceed it. Here, “budget” means the client's target sum, not the contractor's eelarve (estimate) within the meaning of § 639 of the Law of Obligations Act.
Write down what happens in the event of a design error. Does the designer correct the error free of charge, do they reimburse the additional work paid to the contractor and up to what limit, is their liability capped, and is it insured? These terms are normal subjects of negotiation; the law gives them no ready-made answer.
Write in the obligation to keep a list of valid documents. Section 12(8) of regulation no 97 requires it for changes; the contract can require the same list to exist as an annex to the construction contract when it is signed. It is then clear later which version of a drawing was the basis of the price.
Write down what happens during construction. The designer's answers to the contractor's questions, autorijärelevalve (designer's supervision) and the preparation of changes are tasks whose scope must be agreed in the contract. If the client needs them, they must be in the contract together with a response time, because if the client has to give the contractor an instruction and is late in doing so, the contractor may claim compensation for the damage caused by the delay under VÕS § 652(1).
The risk is greater in renovation. Data on an existing building is incomplete and a design error is more likely; why renovation is harder to price is covered in the guide to pricing renovation.
Limitation: a careful reading
The General Part of the Civil Code Act gives two periods that must be read exactly as they are written. Under § 146(1) of the General Part of the Civil Code Act (tsiviilseadustiku üldosa seadus, TsÜS), the limitation period for a claim arising from a transaction, including a contract, is 3 years. Under subsection 2: “The limitation period for a claim arising from a contract for work due to a defect in a building is five years.” Under subsection 4, the period is 10 years in the event of an intentional breach of an obligation.
Whether the 5-year period applies to a design contract depends on the type of contract, which this article does not classify. For defects in construction work and their time limits as against the contractor, see the article on defects and fundamental breach. As regards the designer, it is safer for the client to agree the duration of liability in the contract and to check it with a legal adviser.
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.