Coordinate house design before details reach the site

Make the design understandable to the people building it

Design coordination is the work of making separate decisions fit together before they become physical conflicts. A house can have attractive drawings and still contain unresolved interfaces between structure, enclosure, services and finishes. Coordination asks whether each participant is using the same information, whether the detail is complete enough for the next task and who will answer a question when it is not. This guide describes an editorial working method for household clients and residential professionals. It is not an engineering specification, a contractual allocation of responsibility or a substitute for the professional services required on a particular project.

MBIE's guidance on choosing a designer recognises coordination with other building professionals and attention to site constraints. The appointments for your house should explain who actually performs those services. Do not assume that a designer, builder or project manager is responsible for every interface merely because they attend meetings. List the people engaged, their scope and the decisions they can make. Verify any relevant professional or regulatory requirements in the jurisdiction. The same coordination habit can be useful across Commonwealth markets, but it does not make their approval systems, professional titles or legal duties identical.

Establish one current document register

Create a register that identifies the drawings, specifications, schedules and reports currently issued for each purpose. A document used for discussion may not be suitable for construction. Make that status clear. Include author, revision, issue date and recipient. Keep previous versions available for reference while preventing them from being mistaken for current instructions. A simple disciplined folder can work better than an elaborate platform nobody maintains. Agree who controls the register and how participants are told that a revision affects their work. The household should know where the current approved information can be found.

When a revision arrives, ask what changed and which work it affects. A file with a new date may contain a small note or a significant dimensional alteration. The people pricing, ordering and installing need to know the difference. Request a change description appropriate to the issue. Do not rely on a filename alone to communicate its significance. Confirm receipt where the change affects imminent work, and record any acknowledgement or question. The goal is not to create paperwork for its own sake but to stop someone building from a superseded detail while everyone else assumes the latest information has reached them.

Map the interfaces that deserve early attention

Identify places where one person's work sets a condition for another. Examples include a window meeting a wall build-up, a service passing through a structural element or an external level meeting a threshold. These examples identify coordination topics, not technical solutions. Ask the relevant designers and builder to explain which interfaces are important on your house and when they must be resolved. Put those items on a focused list. A generic catalogue of every possible junction is less useful than a smaller set tied to the actual design and construction sequence.

For each interface, state the question, the responsible participants and the information required. If a product is not selected, record which dimensions or performance assumptions the design currently uses. If two drawings appear inconsistent, identify both references and ask the authors to resolve them. The homeowner should not choose between conflicting technical documents based on which looks more recent. Keep the response with the issue and update the affected documents through the agreed route. Coordination is complete when the people performing the work have a coherent instruction, not merely when a meeting has discussed the problem.

Use buildability input at a useful stage

Ask the builder to identify construction access, sequencing, handling and procurement questions while the design can still respond. Early input can reveal that a detail needs more explanation or that a proposed sequence conflicts with site constraints. Establish the scope and terms of any preconstruction service instead of assuming that informal comments amount to a full review. The designer remains responsible for the services in their appointment, and the builder's suggestions need appropriate assessment. A practical idea should not bypass design review simply because it appears easier to construct.

Record the alternatives considered and what each would change. A proposal may affect appearance, performance, maintenance, cost or approval. Ask the team to consider those consequences together. Avoid deciding an interface solely on the basis of one trade's convenience. For example, moving a service route might simplify installation while creating an access problem later. The correct response depends on the real house and professional advice. The coordination record should show why an option was accepted, which drawings must change and whether any further information is needed before the decision can be implemented.

Turn questions into a managed queue

Use a question register with a unique reference, location, document references, concise question, proposed options if appropriate, owner and required-by date. Distinguish the date an answer would be useful from the date the work will be affected. That gives the team time to respond before the issue becomes urgent. Include photographs or sketches where they clarify the question, but do not let an annotated image silently become an authorised design instruction. State who is expected to answer and whether another person must review the response. Keep open questions visible at coordination meetings.

A useful question is specific enough to answer. Instead of asking whether a room is correct, identify the dimension or interface that does not match the other information. Avoid bundling several unrelated decisions into one email. When an answer arrives, record whether it closes the issue, requires a document revision or creates a further question. A response such as discuss on site is an action, not necessarily a resolution. If the answer affects work already completed or materials ordered, flag that consequence so the team can decide what further assessment is required before proceeding.

Keep household selections connected to technical decisions

The household may see a finish or appliance as an aesthetic choice, while the team needs dimensions, connection requirements, clearances and installation information. Establish a selection schedule that identifies what information is required and when. Ask the builder and designer to distinguish genuinely time-sensitive decisions from those that can wait. Do not make every selection urgent by default. Equally, do not assume an apparently small choice can be changed late without consequences. A light fitting, basin or door handle can interact with other work in ways the household may not anticipate.

Record a selection precisely enough for the appropriate professional to assess and procure it. A screenshot from an online shop may not identify the full product, finish, size or compatible accessories. Keep the manufacturer's current technical information where needed and ask who will check suitability. If the household supplies an item separately, agree the coordination route before ordering it. This guide does not determine who carries contractual risk for an owner-supplied product. The practical point is to make the interface explicit so nobody discovers too late that the selected item requires an unplanned opening, service arrangement or delivery method.

Review changes through all affected disciplines

A change that looks local can have wider effects. Moving a wall may alter structural support, service routes, daylight or furniture clearances. Changing a window can affect more than appearance. Ask the designer to identify who must review the proposal and what approval process applies. In New Zealand, MBIE's variation guidance assigns the building consent authority a role in determining how changes to consented work are handled. Other jurisdictions have their own processes. Do not transfer that exact mechanism universally or assume a homeowner's approval alone is sufficient for a technical or regulatory change.

Keep commercial approval separate from technical acceptance. The household may agree to pay for an option before its design implications are resolved, or a designer may accept a technical proposal without authorising expenditure. The record should identify each required decision. Ask the contract adviser how instructions and variations are formally issued. Until the process is clear, avoid sending messages that could be read as unconditional directions to proceed. A coordinated decision includes the necessary design information, relevant approval, cost and time understanding, and a clear route for communicating the result to the people performing the work.

Use meetings to close issues, not repeat them

Circulate the open coordination items before a meeting and identify the decisions needed. Bring the documents relevant to those items rather than relying on memory. Assign someone to record actions and read back significant decisions before closing the discussion. A meeting note should distinguish an agreed instruction, a proposed option and a question awaiting advice. If a participant is absent, do not assume silence means acceptance of a decision within their responsibility. Send the relevant action through the agreed communication route and identify when confirmation is needed.

Keep the meeting focused on the next construction and design dependencies. A long conversation about a distant finish can obscure an unresolved detail needed next week. Ask the builder to explain the upcoming work and the designer to identify information still being prepared. The homeowner can then see where their own decisions fit. Review overdue questions factually: what is missing, who owns it and what is affected? Avoid using the action list as a record of blame. Its purpose is to make the next step possible and to preserve a shared account of what the team has agreed.

Test the process with a realistic interface

Imagine that a household changes a kitchen appliance after the cabinetry drawings have been reviewed. A weak process sends the new model name to the builder and assumes everything else follows. A coordinated process identifies the exact product, checks dimensions and services, asks the cabinetmaker and designer what changes are needed, considers procurement and programme effects, and records the approved result. The example is illustrative, not an instruction for your own installation. The important habit is to follow the change through every affected responsibility until the documents and planned work agree.

Before work moves to the next stage, ask whether the outstanding questions permit that stage to proceed under the actual project arrangements. Do not use this guide to overrule a builder, inspector or designer's professional judgement. Use it to make the information visible. At completion, reconcile the final records with approved changes so future maintenance does not depend on remembering an informal conversation. Good coordination leaves a useful trail: the current information, the reason for significant decisions, the people who reviewed them and the remaining limitations. That trail is valuable to both the household living in the house and the professionals supporting it.

Coordinate owner-supplied items deliberately

An item purchased directly by the household can still affect the builder's work. Before ordering, identify who checks its suitability, dimensions and connection requirements, who receives it and where it will be kept. Ask about the information needed by the designer and installers. Do not assume that a supplier's promise of easy installation covers the actual house. The product may interact with an opening, structural support, service route or finish. The relevant professionals should assess those interfaces through the agreed process, and the commercial responsibilities should be explained under the actual project arrangements.

Keep delivery expectations connected to the programme. A purchase confirmation does not prove that the right item will arrive on the date needed, undamaged and complete with accessories. Ask what happens if it is delayed or differs from the approved selection. Record the contact responsible for resolving a supply problem so the site team is not left searching through a household member's personal inbox. This is not a recommendation to use owner supply or to avoid it. It is a way to make the route explicit when the household chooses it, preserving a clear link between selection, technical assessment, procurement and installation.

Review coordination after a team change

When a designer, supervisor or other participant changes, schedule a focused transfer of project information. Provide the current document register, open questions, significant decisions and upcoming dependencies. Ask the incoming person to identify anything they cannot understand or verify. Do not assume that access to a shared folder conveys the context behind its contents. A short explanation of why a difficult detail was chosen can prevent an old alternative being revived without recognition of the reasons it was rejected. Keep the transfer proportionate, but treat it as real work rather than an informal introduction.

Check that communication permissions and responsibilities are updated. The household needs to know who now receives questions, who can answer them and which earlier instructions remain current. Retain the history of the change without leaving the former participant as the apparent owner of live actions. Where professional responsibility is affected, obtain the appropriate advice and appointment documentation. The coordination system should remain usable when people change. Its success is measured partly by whether the project can continue from a reliable record, rather than depending entirely on the memory of someone who is no longer involved.

Sources & review notes

Primary sources checked 2026-11-12. Practical examples and working methods are editorial guidance. Confirm project-specific requirements with the named authority; source pages can change.