What Architectural Supervision Is and Why It Is Needed

Architectural (designer's) supervision is the design author following construction to make sure the idea is built correctly. Its tasks, how it differs from technical supervision and how to set it up.

However detailed a design is, construction will raise questions the drawings do not answer. The ground turns out different from what was expected, the chosen stone is no longer available, a builder suggests forming a junction another way. Who decides at such moments? If every question is settled on site by people who do not know the logic of the design, the finished building can differ considerably from the house agreed in the visualisation. Architectural supervision, also known as designer's supervision, is the mechanism set up against this risk.

The concept: who supervises what

Architectural supervision is the participation of the architects and engineers who prepared the design in the construction process. Their aim is to follow whether the work matches the architectural, structural and services solutions in the design and to answer design-related questions promptly.

It should not be confused with quality control of construction. Measuring rebar diameters, reviewing concrete test results and accepting concealed works belong to technical supervision. The design author asks the question from a different angle: does this solution match the idea and calculations in the design? The two forms of supervision complement each other and neither replaces the other.

What architectural supervision does

In practice it works in several directions:

• site visits at key stages: after the foundations, when the frame is complete, when façade and roof works begin;
• clarifying unclear points in the drawings and, where needed, issuing additional detail sheets;
• assessing changes proposed by the contractor or the client;
• checking how substitutions of materials and equipment affect the design;
• recording clear deviations from the design and requiring them to be corrected.

It is not a daily presence. How often visits happen depends on the complexity of the building and the contract: for a small house, calls at key stages may be enough, while a villa with a complex façade needs closer involvement during certain periods.

Changes: the author's central role

Changes are the most frequent source of disputes on site. Say the contractor proposes replacing the façade stone with another one that is in stock. It looks similar but its thickness differs, which changes the projection of window surrounds, the size of the cornice and the fixing system. Or the client wants to remove a wall to join two rooms, and only the design author knows for certain whether that wall is load-bearing.

The author reviews such proposals and gives one of three answers: the change does not affect the design and can be accepted; the change is possible but requires revisions to the drawings; or the change undermines the core solution or safety and is not recommended. In every case the decision is recorded in writing.

Timing matters too. If replacing the façade stone is discussed before the material is ordered, the author can prepare an alternative detail within a few days. Once the stone has been delivered and installation has started, the choice narrows to keeping it as it is or taking it down. It therefore pays to show the author the list of material and equipment orders in advance.

The supervision log

The results of supervision are usually recorded in a log. Each visit notes the date, the work inspected, deviations found, instructions given and deadlines for carrying them out. At the next visit, the previous entries are checked for completion.

The log may look like a formality, but in a dispute it is key evidence. When an unexpected change appears on the façade, these entries show who agreed it, when and why. After construction is finished, the log should be kept together with the design documents.

What happens without it

Without the author's involvement, construction often takes the easiest route. Individually, small decisions seem unimportant: a window is set slightly lower, a cornice is simplified, painted render replaces stone, the ceiling height is reduced because of a beam. Taken together, however, these decisions change the proportions of the building, and the effort invested in the design never reaches the result.

In the structure, the risks are more serious. An opening not provided for in the design, a demolished wall or an additional load undermines the assumptions of the calculation. Such changes should not be made without the opinion of the design author and the structural engineer.

How to organise it

• Set out the scope in the design contract or a separate agreement: number of visits, stages and response times.
• Give the contractor the author's contact details and tell them who design questions should go to.
• Send change proposals to the author in writing rather than settling them between tradesmen.
• Share the author's instructions with technical supervision and the contractor so everyone works from the same information.

Zaferoğlu İnşaat provides both architectural design and construction services. Before construction begins, talk to us about writing into the contract at which stages design supervision will take place and how.