Design and construct versus construct only
Which contract form should a developer use for an apartment project?
Design and construct and construct-only are the two contract forms a developer chooses between when engaging a builder for an apartment project, and the difference is who holds the design. Under design and construct, the builder appoints and manages the design consultants, develops the design to construction documentation and carries the design risk under one contract with one contract sum. Under construct-only, the developer's own consultants document the project, the builder prices those documents and builds to them, and design risk stays with the developer. Design and construct suits developers who want a single point of responsibility and a fixed sum against a defined scope; construct-only suits developers with an in-house design team or completed documentation. Neither is cheaper in the abstract. The design and construct sum includes the design risk the developer would otherwise carry, and the construct-only sum is only as complete as the documents it is priced from.
What transfers under design and construct
The consultants, the coordination between disciplines, the construction documentation and the buildability of the design all become the builder's responsibility. A coordination clash between structure and services found during construction is the builder's problem to resolve within the contract sum, not a variation.
What stays with the developer under construct-only
The design and the documents. If the issued drawings leave something open, the builder seeks an instruction, and the cost of the resolution generally sits with the developer. The developer also holds the consultant agreements and manages the design team through construction.
How the price differs
A design and construct price is set against a documented scope and includes the design work still to be done. A construct-only price is set against issued documents and assumes they are complete. A developer comparing the two should compare the scope each price covers, not the number alone.
Which Calibre uses
Every project in Calibre's record with a stated delivery form was delivered as design and construct. The company also prices construct-only work where the developer brings a documented design.
Reviewed September 2026. Regulatory settings in New South Wales change; confirm the current requirements with your certifier and solicitor.
Related questions
Can a project start construct-only and become design and construct?
Yes. If the developer asks the builder to take over the consultants for the remaining coordination, the contract changes to design and construct from that point.
Is design and construct faster?
Often, because design development and procurement overlap under one programme rather than running in sequence under separate agreements. It depends on how complete the design is when the builder is engaged.
Who appoints the certifier?
Under both forms the certifier is appointed by the developer as the person having benefit of the consent, though under design and construct the builder usually manages the relationship day to day.
Discuss a site.
Send the address and the stage the project has reached. A director reads every enquiry and replies within one business day.