Building performance
Rosedale in Glen Iris is a recent example. An architect-designed home where the building performance was specified through the TCON Pre-Construction Program with the energy rater, alongside Webster Architecture and Interiors. The thermal envelope, the glazing package and the slab insulation strategy were resolved before documentation closed, well past the NCC 7-star minimum.
The completed home performs the way it was designed to. Building performance is integrated across thermal, acoustic, moisture and air quality, specified during design through early contractor involvement, documented through construction and verified at handover.
At this price band, double glazing and a 7-star energy rating are standard. TCON does not build certified Passive House, but every home is energy-rated, built to a tight envelope, and taken beyond the minimum Australian standards.
Building performance is a design-stage decision, not a retrofit
The most important thing to understand about building performance is when it is decided. Performance outcomes, how a home holds temperature, how the envelope manages moisture, how spaces are separated acoustically, how efficiently the home runs, depend on decisions made before documentation is finalised.
Window systems, envelope sealing, roof ventilation, slab insulation and the treatment of thermal bridges at junctions are all design decisions. Once the design is documented and the home is being built, these decisions are expensive to revisit and often compromise the architecture when they are forced in late.
Building performance is specified during design or it is paid for twice.
How TCON works with energy raters during the Pre-Construction Program
TCON works with experienced energy raters during the TCON Pre-Construction Program. The rater's input does not sit in a separate compliance stream.
It feeds directly into the buildability review and the procurement strategy, so the performance decisions are made alongside the cost and construction decisions rather than after them. The rater models the home's performance while the design is still flexible. The implications for the window schedule, the envelope detailing, and the procurement of performance-critical items are captured in the same Pre-Construction work that settles the budget.
The elements TCON advocates for
Specific design decisions carry most of the performance outcome on an architectural home:
Thermally broken windows, so the window framing does not conduct heat across the envelope.
Sealed building envelopes, so air movement is controlled rather than leaking through unsealed junctions and penetrations.
Ventilated roof spaces, so moisture and heat are managed above the ceiling line.
Insulated slabs, so the ground does not draw heat out of the home.
Thermal bridging control at junctions, so the points where materials meet do not become the weak points in the envelope.
Each of these has to be designed in. None of them retrofits well.
Why these decisions have to be made at concept design
Retrofitting performance compromises architectural intent and adds significant cost. A window system changed after documentation affects the reveals, the sightlines and the budget.
Envelope sealing addressed after the design is set means detailing the junctions twice. Slab insulation added late is often not possible at all.
Early specification protects both the architecture and the performance, because the performance decisions and the design decisions are made together, by the same team, at the same time.
Where most homes fall short
Even where performance is specified, the gap between specification and execution is well documented on Australian residential projects. Air-tightness targets are set but junctions are not detailed and not inspected. Insulation is specified but installation gaps reduce effective performance.
Acoustic separation is detailed but compromised by service penetrations cut through after the inspection. TCON closes this gap by treating performance as a documented, inspected and verified discipline. Air-tightness, where specified, is tested before linings go on.
Insulation is inspected for continuity. The completed home is handed over with the performance evidence as part of the documentation pack.
The relationship to negotiated tender and the Pre-Construction Program
Building performance decisions are a natural output of the early contractor involvement between architect and builder. The rater's modelling, the buildability review and the procurement strategy are developed together during the Pre-Construction Program. They carry into the negotiated tender as priced, specified, deliverable scope. Not as aspirations the build then has to accommodate.
Performance specified this way is performance the contract sum reflects. TCON delivers building performance on architect-designed homes for practices including Webster Architecture and Interiors and Pleysier Perkins.
Frequently asked questions
Yes, within the constraints of the retained fabric. The methodology is developed during Pre-Construction with the architect and the relevant consultants, so older homes can be upgraded towards contemporary thermal, moisture and acoustic performance without compromising the heritage fabric being retained.
TCON works with experienced energy raters during Pre-Construction. The relationship is project-specific rather than a published panel, so the right rater is matched to the project.
Building with TCON
Considered architecture demands considered building. Building with TCON is a complete account of how TCON works. Available on request and reviewed personally by Tim before release.
Request a copy of Building with TCON.
Related. Capability, Quality assurance.