“Designer’s supervision”, “technical inspection” and “project management” are often used interchangeably during a home renovation. They are not the same service. Each addresses a different question and requires different competences. Confusion leads to unrealistic expectations: an owner may assume the interior designer will certify electrical safety, or that a site coordinator can authorize changes to the design.
In brief: designer or author’s supervision helps ensure that agreed design decisions are interpreted and implemented correctly. Technical checks assess specified aspects of workmanship, compliance or safety within the examiner’s competence. Project management coordinates people, timing, budget, deliveries and change decisions. Statutory construction supervision under Bulgarian law is a separate regulated activity wherever the law requires it.
Why the distinction matters
Consider an apartment renovation with bespoke kitchen cabinetry, concealed lighting and relocated plumbing. The designer has detailed the correct positions, but the plumber receives an outdated drawing. The cabinetry is manufactured before final site dimensions are verified, and the drain is in the wrong position. A technical expert may identify the error, the designer may resolve the detail, and the project manager must coordinate the correction and its timing and cost. Three different functions are needed.
A contract promising simply “supervision” tells you very little. Ask what is inspected, how frequently, by whom, with what authority and how decisions are documented. Otherwise everyone may assume someone else was responsible.
Comparison of the roles
| Role | Central question | Typical tasks | Not automatically included |
|---|---|---|---|
| Author’s or designer’s supervision | Is the intended design being followed? | Design clarification, detailing and agreed design changes | Daily site attendance and all procurement |
| Technical inspection | Does specific work meet the relevant requirements? | Measurements, checks, specialist testing and reports | The legal role of a statutory construction supervisor |
| Project management | Who coordinates the complete delivery? | Programme, budget, communication, dependencies, decisions | Qualification to certify every technical discipline |
| Statutory construction supervision | Are the applicable legal duties met? | Regulated inspections and documentation | A requirement for every repainting job or furniture change |
The precise requirements depend on what is being built or altered. If a renovation involves structural elements, major changes or questions about approvals, consult an appropriately qualified designer or construction-law specialist before starting.
Designer’s supervision on an interior project
During implementation, the interior designer can review lighting positions, finish selections, junctions between materials, built-in niche dimensions, cabinet details and the visual coherence of approved substitutions. When conditions on site differ from the drawing, the designer can develop a solution that preserves the intent and usability of the space.
There is an important legal distinction between author’s supervision of an approved investment design where the Bulgarian Spatial Development Act applies, and an optional contractual service sometimes described as “interior design supervision” for ordinary decorative work. The law and the individual contract determine scope and obligations. For construction in categories one to five, Bulgarian law requires author’s supervision of the relevant design disciplines; whether a particular renovation falls within that regime needs project-specific professional assessment.
Legal reference: Article 162(2) of the Bulgarian Spatial Development Act. Confirm the currently applicable rules and approval regime for the individual project.
When do you need a specialist technical check?
An interior designer may compare a partition position or furniture detail with the drawing, but electrical safety, structural integrity, specialist fire requirements and testing of installations require suitably competent professionals. Hiring an interior project manager does not automatically authorize that person to sign specialist certificates.
Identify the critical works before construction begins. Record who performs them, who inspects them and what evidence is needed before covering them. Waterproofing, concealed drainage and electrical routes all benefit from predetermined hold points. The stage-by-stage approach is explained in our renovation quality-control guide.
What good project management actually does
Project management is largely about dependencies. A cabinetmaker should not finalize production on assumptions about unfinished walls and floor levels. A tiler should not arrive before the substrate is ready. The manager keeps track of prerequisites, decisions and handovers between trades, updating the programme when something changes.
Effective tools can be simple: an up-to-date schedule, an issues register, an approved change log, a budget by work package and a short weekly report. At minimum, the report should show what has finished, what blocks the next activity, who owns the decision and when it must be made.
Coordination does not necessarily grant a manager the right to place orders or authorize spending in the owner’s name. Any such authority should be explicit, with approval thresholds and a clear audit trail.
Which level of support fits your renovation?
Cosmetic refurbishment. Painting, replacing readily available furniture and limited work may need a clear brief, a reliable contractor, sensible coordination and a structured handover. Specialist checks are still required for any regulated work involved.
Full apartment renovation. Moving service points, rebuilding bathrooms, installing bespoke kitchens and coordinating several trades make technical drawings, specialist checks, designer’s supervision and a single project coordinator much more valuable. Interfaces between trades create significant risk.
Major alteration or regulated construction. Where structural elements, permissions or other legal requirements may be involved, establish the appropriate design, approval and supervision framework first. Interior design coordination does not replace statutory duties.
What to include in the service agreement
Specify the drawings and disciplines covered, the number and timing of visits, remote review arrangements, response times, the approval process for changes, who signs which records, who contacts contractors, whether purchasing and delivery coordination are included, and the charge for extra visits. Avoid undefined phrases such as “complete control” without an attached scope.
A useful procedure is to require the contractor to notify the responsible parties before concealing key services or waterproofing, supply photographs and required test records, and obtain the agreed clearance before proceeding. The exact contract wording must reflect the project and applicable requirements.
How to avoid overlapping responsibilities
Create a decision pathway: who reports a problem, who proposes a technically acceptable solution, who approves design changes, who signs off extra expenditure and who updates the schedule. Number revisions and date decisions. Where two contractors dispute the cause of an issue, a shared documented condition report is more productive than informal blame.
Late decisions can have a much wider impact than the time spent discussing them. A delayed cabinet detail may affect production and installation dates. See our renovation schedule guide for practical schedule controls.
Frequently asked questions
Is author’s supervision mandatory for every apartment renovation?
No single rule applies to every activity described as a renovation. Legal obligations depend on the nature and classification of the works. Where the Spatial Development Act requires supervision for the applicable construction, it must be provided.
Can one company provide all three services?
A team may coordinate several services, but regulated and specialist checks must still be performed by suitably qualified persons. List the scope of each service separately.
Does the manager have to visit the site every day?
Not necessarily. What matters is an appropriate inspection schedule, fast decisions, meaningful reporting and attendance at critical stages. Complex sites may require more frequent presence.
How do I assess value for money?
Compare the fee with the real scope, risks, number of contractors, inspection deliverables and time you would otherwise spend managing the project. Visit counts alone are not a sufficient metric.
The right combination is more important than the job title
Start with the project scope, technical requirements and responsibility matrix. Then arrange design review, specialist inspection and coordination as complementary functions. See our contractor-selection guide for choosing the team that will actually build the project.
Planning a renovation or furnishing project in Sofia?
Tell Atmosphera about your space, budget and priorities to discuss a suitable design and implementation scope.
