Why every project team should know who does what
A building is designed by a team, not by one consultant. The client sets the brief, the architect leads and coordinate the design, and the building services engineers (mechanical, electrical, fire and hydraulic) make the building work.
Most design problems we see on site are not technical failures. They are gaps between disciplines: a switchboard room that is too small, a mechanical unit nobody gave power to, or a light fittings clashing with the mechanical ventilation grilles or a fire interface that two consultants each thought the other was covering. Either way comminucation is the key and good architects understands this and communicates effectively with all the team members of the project. Send the floor plans and expect a full package is a way of doing a design in a poor way.
This guide explains the role of each discipline at every stage of building services design, from concept design through schematic design, detailed design, tender, construction and the Defects Liability Period (DLP). It is written from an electrical engineer's point of view, for architects, project managers, builders and fellow consultants working on commercial, education, health and residential projects across Melbourne, Victoria, Queensland and NSW.
Stage names vary between clients and contracts. Some projects split detailed design into Design Development (DD) and Contract Documentation (CD). The responsibilities below still apply.
Who is in a building services design team?
The architect is usually the lead consultant, coordinating the engineers on behalf of the client and project manager. The building surveyor sits outside the design team and checks it independently.
The electrical engineer works alongside the other engineering consultants under the architect's coordination, then reviews the builder's shop drawings during construction.
Client (owner, developer or end user): Sets the brief, budget and program, makes the key decisions and provides existing information such as as-built drawings, asset registers and their own design standards. This becomes a main objective of the client to follow a specific set of standards that suits their infrastructure, they almost always tend to align with Australian Standards and there are some might go a little sideways from standards and therefore should be queried or clarified with client at the start or detailed design stages to avoid conflicts later down the track.
Project manager (PM): Runs the project for the client. Manages program, cost, risk, consultant appointments and change control. Often acts as the Superintendent under the construction contract. If the project manager does the communications effectively and in a timely manner then things will go in the right directions but unfortunately lots of PM actually just want to finish the works and go holidays but this is going to destroy the project as I described earlier the design is effectively the coordination of various services. If a communication was not relayed to architect from an electrical engineer for example the changes required for a DB placement in an egress pathway. This will result in a big variation in the future as the building compliance is not achieved against the NCC.
Architect: Leads the design and coordination. Responsible for space planning, plant rooms, risers, ceiling space and the overall coordinated drawing set. Spatial allowances for various disciplines is really important in relation to a services consultant as the space is crucial. It becomes hard when the space utilisation of the building is more than 90% and therefore cutting corners for various spatial requirements as per Australian Standards and NCC. This is where it is important to have a consultant who knows what a client is looking for and what an architect is looking for so the moment you require a modification instead of going back to Australian Standards or seniors all the time to check whether that modification will comply with standards.
Building surveyor: Called a Relevant Building Surveyor in Victoria, a building certifier in Queensland and a registered certifier in NSW. Assesses compliance with the National Construction Code (NCC), issues the building permit and the occupancy permit or final certificate. As a team of electrical engineers we rely our designs on the report prepared by building surveyor especially for the building class identification. The emergency lighting and exit lighting reuqirement basic is from this decision and if got wrong will be a painful excercise later down the track. For example, if the report has identified as no life safety requirement for the building due to NCC requirements, and if you found it requires a single life safety device the electrical design changes a lot to accommodate this one particular requirement. One of the best firms I have used when requestd by PM or Architects Authorised Building Surveyors
Structural engineer: Designs the frame, slabs and footings, and checks plant loads, penetrations and supports for heavy services equipment. This most crucial interms of handling the weight of all equipment from electrical and mechcnial perspective if you got this wrong there is no way of going back to changing this half down the way. Probably one of the worst hit PII claim category out of the services.
Civil engineer: Designs site drainage, stormwater, levels, pavements and external trenching. This is important as the ground services will be the source of power to the site and communication with any outside network etc. Keeping the utilities infrastructure incoming designed in a proper way is as important as designing a building services design. Please take a read of the external lighting design requirements which we regularly coordinate with Civil engineers for compliance against the AS 1158, AS 4282 compliance.
Mechanical engineer: Designs heating, ventilation and air conditioning (HVAC), exhaust, smoke control and the building management system (BMS). I would say probably one of the most imprtant team members for our electrical design to be correct. For example, my first question to you if you are mech consultant in a project where we are electrical designer is to say the mechanical loads, if you got this wrong the electrical infrastructure of the building have no capacity to accommodate the loads as required by the building and threfore will require re design. One of the common mistakes when converting a space from one usage to other is changing the workspaces layouts and accommodate more people but not caring about the air circulation and lighting in the space. The result is almost always rectification works that will cost them 10-20 times what it will cost them if they have engaged a mechanical consultant.
Electrical engineer: Designs the power supply from the electricity network, main switchboards, distribution, lighting, emergency lighting, communications, security, lightning protection, solar PV and EV charging. This is us honestly we communicate daily with these consultants for proper coordination. Infact the most important part of a building is still electrical design as if you think a building is made without electricity can it survive? But without mech, hyd or fire it can still work but no electricity? Do you want to have a confidential discussion about your project give me a call or an email I can give you a free preliminary review of the designs complated by someone else. We regularly undertake peer reviews with NDA disclosure so the client can have peace of mind of seen by two eyes and compliant.
Fire services engineer: Designs sprinklers, hydrants, hose reels, fire detection and alarm systems and emergency warning systems. A separate fire safety engineer may prepare performance solutions. Dry fire comes with electrical but the safety solutions should be designed by fire engineer.
Hydraulic engineer: Designs cold and hot water, sanitary drainage, roof stormwater, gas and rainwater reuse.
Specialist consultants: ESD and sustainability (NCC Section J, Green Star, NABERS), acoustic, vertical transport (lifts), access (DDA), audio visual, security, landscape and the quantity surveyor or cost planner. We specialises in green star projects and we have got green star 6 star projects across Sydney and more than happy to check the compliance reuqirements for your points credit whether be it is Credit 11, 16 or 27.
Builder and subcontractors: Price the design at tender, then build it, prepare shop drawings and hand over the completed building. Most important part of the project as the quality of the selected contractor will influence of the project outcome.
Stage 1: Concept design
Concept design tests whether the project can work on the site, within the budget. Decisions made here, such as where plant rooms go and whether a substation is needed, are the hardest and most expensive to change later.
Typical outputs: concept sketches, massing and floor plan options, a services concept report and an early cost estimate.
Client: Defines the brief, functional needs, budget, program and sustainability targets. Shares any client design standards early.
Project manager: Sets up the program, appoints consultants and agrees a scope or responsibility matrix so every item has an owner.
Architect: Develops site layout and massing, and allocates space for plant rooms, risers, switch rooms and the substation.
Building surveyor: Gives early advice on building classification, fire compartments, egress and likely performance solutions.
Structural: Proposes the structural system, grid and floor depths that the services must fit within.
Mechanical: Compares HVAC system options and sizes plant space on roofs and in plant rooms.
Electrical: Estimates the preliminary maximum demand, checks supply capacity with the electricity distributor, confirms whether a kiosk substation or new supply is needed, sizes the main switch room and reviews existing site infrastructure. Do you want to undertake a preliminary assessment for a feasibility study into the existing infrastructure to see if they can handle or you need a new substation to cater for the new loads. Contact us for a free quote.
Fire services: Confirms what the NCC requires (sprinklers, hydrants, detection), checks water supply and allows for tanks, pumps and booster locations.
Hydraulic: Checks authority water, sewer and gas capacity and proposes the hot water strategy.
ESD and specialists: Set energy, acoustic and accessibility targets that shape the services design.
Cost planner: Prepares the first cost plan. An OPOC could be produced by us for coordination purposed.
Stage 2: Schematic design
Schematic design fixes the preferred concept and locks in the major systems, plant spaces and services routes. By the end, every discipline should know where its main equipment sits and how it connects.
Typical outputs: schematic floor plans, system schematics, a services design report, an NCC compliance report and an updated cost plan.
Client: Reviews and signs off the schematic design, runs user group consultations and confirms the budget.
Project manager: Runs design reviews, value management and change control.
Architect: Refines plans and ceiling heights, starts reflected ceiling plans and coordinates services zones.
Building surveyor: Reviews the design against the NCC and confirms which performance solutions are needed.
Structural: Sizes main members and agrees penetration zones and plant loads.
Mechanical: Selects systems, routes main ductwork and pipework, and issues plant electrical loads to the electrical engineer.
Electrical: Prepares the single line diagram (SLD), confirms maximum demand, lodges the supply application with the electricity distributor, locates switchboards and risers, and sets the lighting, lighting control, emergency lighting, communications and security strategies. Section J lighting and power allowances are also set here.
Fire services: Prepares system schematics, sizes tanks and pumps, sets detection zoning and coordinates with the fire engineering report.
Hydraulic: Prepares schematics, main routes and plant selections, and issues pump and water heater loads to electrical.
All disciplines: Coordinate ceiling and riser space, often in a shared 3D (BIM) model.
Stage 3: Detailed design (design development and documentation)
Detailed design turns the schematic into a fully coordinated set of drawings and specifications that a builder can price and build from. Gaps left here become variations and delays on site.
Typical outputs: tender drawings, technical specifications, equipment schedules, calculations and design compliance certificates.
Client: Gives final approvals and signs off the design for tender.
Project manager: Manages the documentation program, design freeze and authority approvals.
Architect: Completes coordinated drawings, finishes, reflected ceiling plans and door schedules (including doors with access control).
Building surveyor: Assesses the documentation and performance solutions, and issues the building permit before works start.
Structural: Finalises structural drawings, penetration details and equipment supports.
Mechanical: Completes layouts, equipment schedules, BMS points lists and fire mode operation, and issues final electrical loads.
Electrical: Completes lighting layouts with lighting calculations to AS/NZS 1680, emergency and exit lighting to AS 2293, cable sizing and voltage drop to AS/NZS 3008, fault level and protection discrimination studies, switchboard schedules and layouts to AS/NZS 61439, power and data layouts, security and access control, lightning protection to AS/NZS 1768, NCC Section J compliance and the electrical specification, all designed to AS/NZS 3000 (Wiring Rules).
Fire services: Completes sprinkler, hydrant and detection layouts to AS 2118.1, AS 2419.1 and AS 1670.1, plus interfaces with mechanical shutdown and electrical power.
Hydraulic: Completes layouts and schedules to AS/NZS 3500.
Tip: agree the interface matrix. For each piece of equipment, record who supplies it, who powers it, who controls it and who commissions it. For example, the electrical engineer provides the circuit and isolator, the mechanical engineer provides the unit and controls. This one table prevents more site disputes than any other document.
Stage 4: Tender
At tender, builders and subcontractors price the design documents and the client selects a contractor. The quality of the documents directly affects how close the tender prices are to the cost plan.
Typical outputs: tender queries and answers, addenda, tender comparison and a recommendation report.
Client: Approves the tender list, selects the contractor and signs the contract.
Project manager: Runs the tender, manages queries, evaluates tenders and makes a recommendation.
Architect: Answers design queries and issues addenda.
Engineering consultants (electrical, mechanical, fire, hydraulic, structural): Answer technical queries, issue addenda, check tenders for technical compliance, review alternative products and identify scope gaps or exclusions.
Electrical: Typically reviews tendered switchboard manufacturers, light fitting alternatives ("equal and approved" offers), cabling and containment allowances, and any exclusions such as supply authority charges.
Cost planner: Compares tender prices against the cost plan.
On design and construct (D&C) projects, consultants are often novated to the builder after tender. The builder then becomes the consultant's client for the rest of the project.
Stage 5: Construction
During construction, the builder builds and the design team checks that what is installed matches the design and the standards. The stage ends at practical completion, when the building is handed over.
Typical outputs: shop drawing reviews, RFI responses, site inspection reports, test witnessing records, defects lists, as-built drawings and operation and maintenance (O&M) manuals.
Client: Decides on variations, pays progress claims and prepares for occupation.
Project manager or Superintendent: Administers the contract, assesses variations, extensions of time and progress claims, chairs site meetings and certifies practical completion.
Builder: Builds the works, coordinates trades, submits shop drawings, samples and requests for information (RFIs), and commissions the systems.
Architect: Answers RFIs, inspects the works and coordinates design changes.
Building surveyor: Carries out mandatory inspections and issues the occupancy permit or final certificate.
Structural: Inspects footings, reinforcement and steelwork.
Mechanical, fire and hydraulic: Review shop drawings, inspect installations and witness commissioning.
Electrical: Reviews switchboard, lighting and containment shop drawings, answers RFIs, inspects the installation, witnesses switchboard factory tests and site testing (insulation resistance, RCD and emergency lighting discharge tests), and checks certificates of electrical compliance, as-built drawings and O&M manuals before sign-off.
At practical completion, every consultant inspects the works and issues a defects list. Systems must be tested, commissioned and documented before handover.
Stage 6: Defects Liability Period (DLP)
The Defects Liability Period starts at practical completion and is commonly 12 months, though the contract sets the actual length. During the DLP, the builder must fix defects that appear, and the client usually holds back a retention or bank guarantee until it ends.
Typical outputs: defect notices, rectification records, end-of-DLP inspection reports and the final certificate.
Client or facility manager: Operates the building, reports defects and keeps maintenance records. In Victoria, the owner must also maintain essential safety measures such as emergency lighting and fire systems.
Project manager or Superintendent: Manages defect notices, confirms rectification and releases security at the end of the DLP.
Builder: Fixes defects and carries out any maintenance included in the contract, such as seasonal tuning of mechanical systems.
Architect and engineers: Investigate reported issues, confirm whether they are defects or operational problems, and carry out the end-of-DLP inspection.
Electrical: Typically investigates nuisance tripping, lighting levels or control complaints, checks emergency lighting test records and confirms as-built drawings reflect what was installed.
When should you engage an electrical engineer?
Engage the electrical engineer at concept design, not after the floor plans are fixed. Power supply and substation requirements can change site layout, program and budget more than almost any other services item.
The electrical engineer's key deliverables at each stage:
Concept: maximum demand estimate, supply capacity check, substation and switch room allowance.
Schematic: single line diagram, supply application, switchboard and riser locations, lighting and systems strategy.
Detailed design: lighting design, cable and protection calculations, switchboard design, layouts and specification.
Tender: technical review of tenders and alternative products.
Construction: shop drawing reviews, site inspections, test witnessing and compliance sign-off.
DLP: defect investigation and end-of-DLP inspection.
Common problems when electrical is engaged late:
Switch rooms and risers too small for compliant clearances.
No space allowed for a substation or kiosk on site.
Supply authority lead times delaying building occupation.
Mechanical and hydraulic equipment without coordinated power or isolators.
Lighting that fails Section J or does not suit the architecture.
Frequently asked questions
What is building services design? Building services design is the engineering of the systems that make a building safe, comfortable and usable: electrical, mechanical (HVAC), fire, hydraulic, communications, security and vertical transport.
What does an electrical consultant do on a building project? An electrical consultant designs the power supply, switchboards, lighting, emergency lighting, communications and security systems, documents them for tender, and inspects and certifies the installation during construction.
Who is the lead consultant in building design? Usually the architect. On services-heavy projects such as plant upgrades or switchboard replacements, the electrical or mechanical engineer may lead.
What is the difference between schematic design and detailed design? Schematic design fixes the systems, plant spaces and main routes. Detailed design produces the fully coordinated drawings and specifications used for pricing and construction.
What is the Defects Liability Period (DLP)? The DLP is the period after practical completion, commonly 12 months, during which the builder must fix defects in the works. It is a wise idea to engage us for DLP period for periodic inspections to get this performance tuned to enable full efficiency of the building performance. This is where the Power Factor Correction equipment and Harmonic Filter gets introduced if required.
Work with an electrical engineer who understands the whole team
J George Consulting is an independent building services electrical consultancy based in Melbourne. We provide electrical design, lighting design and compliance sign-off for architects, project managers, builders and fellow consultants across Victoria, Queensland and NSW.
Our principal engineer holds CPEng, NER, RPEQ and RPEV registrations, so we can design and certify electrical services across all three states.
Planning a project? Contact us to bring electrical in at concept stage and avoid costly late changes.
