Will the atrium overheat in February? Will the classroom stay fresh with the windows open? Where does the air actually go? We answer those questions at design stage, when a bigger opening or a deeper overhang is still a line on a drawing.
Request a Fee Proposal →Send us your drawings and tell us what you want to test. We'll confirm the scope and send you a quote.
Makao models how air moves through a building and how comfortable people will be in it. We develop natural ventilation strategies, model thermal comfort with PMV/PPD, adaptive comfort or CIBSE TM52 overheating criteria, and use CFD for detailed internal airflow. The results inform design and support your NCC and Green Star documentation.
Most comfort problems are decided early: by orientation, glazing, shading, thermal mass and where the openings go. Once those are fixed, the usual fix is more mechanical plant. Modelling at design stage shows the team how a space will behave before it is built.
Openable area on a drawing doesn't guarantee air movement. Cross-ventilation and stack effect depend on opening positions, heights and paths through the plan. We test the strategy and show where it works and where it doesn't.
A sealed, air-conditioned office and a naturally ventilated school need different comfort tests. We agree the method with your team first: PMV/PPD, adaptive comfort, TM52 overheating criteria or the NCC J1V3 criteria.
Zone models give whole-room averages. CFD shows the air speed at a desk, the temperature layers in an atrium and the dead spots in a deep plan. We use it where those details change a design decision.
PMV/PPD (ISO 7730, ASHRAE Standard 55). PMV predicts the average thermal sensation of a group of people on a seven-point scale from cold (−3) to hot (+3). PPD estimates the percentage likely to be dissatisfied. Both are mainly used for mechanically conditioned spaces. For the NCC J1V3 option, PMV is calculated to ANSI/ASHRAE Standard 55.
Adaptive comfort (ASHRAE Standard 55). In occupant-controlled, naturally conditioned spaces, people accept a wider range of temperatures that follows the outdoor climate. The adaptive method sets acceptable indoor operative temperatures from outdoor conditions. It applies only when the conditions in the standard are met, such as no mechanical cooling.
CIBSE TM52 overheating. A CIBSE (UK) method for free-running buildings that uses adaptive limits and three criteria covering how often, by how much and how far temperatures exceed the comfort limit. TM52 is not an NCC method. We use it when your brief, client or rating scheme calls for an overheating assessment.
NCC-based (J1V3). The NCC has no general comfort requirement. It links comfort to the Section J Verification Methods. Under NCC 2025 J1V3(1)(b), one option for a Class 5 building is a PMV of −1 to +1 across at least 95% of the floor area of occupied zones for at least 98% of annual operating hours. Another option, for any building the method covers, is keeping dry-bulb temperatures across at least 95% of the floor area of occupied zones, for at least 95% of annual operating hours, between 18°C and 25°C in conditioned spaces with transitory occupancy and 21°C and 24°C in other conditioned spaces. J1V3(1)(b) also has peak-load options, set by climate zone (cooling in climate zone 1, heating in climate zone 8, and both in climate zones 2 to 7). The comfort criteria apply to J1V3, which covers Class 3 and 5 to 9 buildings, not Class 2. We model whichever option your J1V3 pathway uses.
Green Star. Green Star Buildings includes a Thermal Comfort credit. We model to the criteria in the Submission Guidelines version your project is registered under.
Performance Requirements: F6P3 outdoor air supply; F6P4 and F6P5 for mechanical air-handling systems and contaminated air. Deemed-to-Satisfy: F6D6 accepts natural ventilation to F6D7 or AS 1668.4, or mechanical ventilation to AS 1668.2 and AS/NZS 3666.1. F6D7 needs an openable area of at least 5% of the room's floor area, open to a suitable court or space open to the sky, an open verandah or similar, or an adjoining room under F6D8. Verification Method: F6V1 indoor air quality (Table F6V1 contaminant limits, e.g. CO₂ ≤ 850 ppm over 8 hours) for Class 2, 3, 5, 6, 9b and 9c buildings and Class 4 parts.
Performance Requirement: H4P5 ventilation. Deemed-to-Satisfy: H4D7 points to Part 10.6 of the ABCB Housing Provisions, or AS 1668.4 for natural ventilation. Verification Method: H4V3 indoor air quality (Class 1).
We provide design input and modelling evidence. Mechanical ventilation design and AS 1668.2 sizing are outside our scope. Your relevant building surveyor decides compliance.
Melbourne-based, working Australia-wide.
We assess opening sizes, positions and air paths, and test cross-ventilation and stack-driven strategies. We report how they perform and recommend design changes.
Annual comfort modelling of occupied spaces against PMV/PPD, adaptive comfort, CIBSE TM52 or the NCC J1V3(1)(b) criteria, as agreed with your team.
Detailed internal airflow and temperature modelling for natural ventilation, atria, façade cavities, and naturally ventilated and mixed-mode spaces. We also use CFD for carpark ventilation, to test predicted carbon monoxide levels in Class 7a carparks against the limits in the NCC F6V2 Verification Method, and for exhaust re-entrainment and pollutant dispersion studies around the building. F6V2 is used as part of a Performance Solution, and your building surveyor decides whether it is accepted. Carpark mechanical ventilation design and AS 1668.2 sizing stay with your services engineer.
Pedestrian wind comfort is outside our scope. We can refer you to a wind engineer.
Reports present modelling results. They don't certify compliance or guarantee comfort in use.
You send drawings and tell us what you want to test. We confirm scope and give you a quote.
We agree the comfort method, criteria and spaces with your team, and with your building surveyor where the work supports a Performance Solution.
We build the model, test design options and share early results while the design can still change.
We issue the report and recommendations, and update them if the design changes within the quoted scope.
Turnaround: Timeframes confirmed at quote; fast-track available for urgent projects.
Drawings (plans, sections, elevations) with a north point; window and opening schedules, including openable areas and how they open; construction details; shading details; the intended ventilation and air-conditioning strategy; occupancy and hours of use; and any comfort criteria in your brief or rating target.
Thermal comfort modelling predicts how warm or cool people will feel in a space across a typical year. It combines air temperature, radiant temperature, air speed, humidity, clothing and activity. Results are reported against a recognised method, such as PMV/PPD under ISO 7730 or ASHRAE Standard 55, or the adaptive comfort method for naturally ventilated spaces.
PMV (Predicted Mean Vote) predicts the average thermal sensation of a group on a seven-point scale from cold to hot. PPD (Predicted Percentage Dissatisfied) estimates the share of people likely to be uncomfortable. Both are mainly used for mechanically conditioned spaces. The adaptive comfort method in ASHRAE Standard 55 relates acceptable indoor temperatures to outdoor conditions, and applies to occupant-controlled, naturally conditioned spaces without mechanical cooling.
CIBSE TM52 is a CIBSE (UK) method for assessing overheating risk in free-running buildings, published by the Chartered Institution of Building Services Engineers. It uses adaptive comfort limits and three criteria: how often, how much and how far temperatures exceed the comfort limit. It is not an NCC method. In Australia we use it as a design-brief criterion when a client or rating scheme asks for an overheating assessment.
Not generally. The NCC links thermal comfort to the Section J Verification Methods. Under NCC 2025 J1V3(1)(b), one option for a Class 5 building is a PMV between -1 and +1 across at least 95% of the floor area of occupied zones for at least 98% of annual operating hours. Another option is keeping dry-bulb temperatures across at least 95% of the floor area of occupied zones, for at least 95% of annual operating hours, between 18°C and 25°C in conditioned spaces with transitory occupancy and 21°C and 24°C in other conditioned spaces. Your relevant building surveyor decides compliance.
For Class 2 to 9 buildings, NCC 2025 Volume One Part F6 requires occupied spaces to have ventilation with outdoor air (F6P3). Under the Deemed-to-Satisfy Provisions, F6D6 accepts natural ventilation complying with F6D7 or AS 1668.4, or mechanical ventilation complying with AS 1668.2 and AS/NZS 3666.1. F6D7 requires openable windows, doors or other devices with a ventilating area of at least 5% of the room's floor area, open to a suitable court or space open to the sky, an open verandah or similar, or an adjoining room under F6D8. For houses, Volume Two H4P5 and H4D7 point to Part 10.6 of the ABCB Housing Provisions or AS 1668.4.
NCC 2025 Volume One F6V1 is a Verification Method for indoor air quality in Class 2, 3, 5, 6, 9b and 9c buildings and Class 4 parts. It is met when ventilation with outdoor air keeps contaminant levels within Table F6V1 under typical conditions, for example carbon dioxide at or below 850 ppm averaged over eight hours. Ventilation modelling can provide part of the evidence, such as predicted carbon dioxide levels. The other Table F6V1 limits need other evidence, such as material selection or testing. Your relevant building surveyor decides whether it complies.
Computational fluid dynamics (CFD) simulates air movement and temperature in detail. We use it for internal airflow and air speeds, cross-ventilation and stack-driven ventilation, airflow and temperature in atria and façade cavities, comfort in naturally ventilated and mixed-mode spaces, ventilation of Class 7a carparks against the NCC F6V2 carbon monoxide limits (as evidence for a Performance Solution that your building surveyor decides whether to accept; ventilation design stays with your services engineer), and exhaust re-entrainment and pollutant dispersion. It shows where air goes and where it stalls, which simpler zone models can't.
Green Star Buildings includes a Thermal Comfort credit. Comfort modelling, run to the criteria in the Submission Guidelines version your project is registered under, provides evidence for it. Ventilation and indoor air modelling can also inform the Clean Air credit. The Green Building Council of Australia assesses the submission.
Timeframes confirmed at quote; fast-track available for urgent projects. Fees depend on the building, the number of spaces and options, and whether CFD is needed. Send us your drawings and brief and we'll give you a quote.
The same model can test comfort, ventilation, daylight and energy, so options are compared on the same basis.
We use PMV/PPD, adaptive comfort, TM52 or NCC criteria to suit the space and the brief, and explain why.
We model and advise. Mechanical design stays with your services engineer, and your building surveyor decides compliance.
Our founder, Kelvin Mureithi: Green Star Accredited Professional, ISAP, Engineers Australia member.
Reviewed by Kelvin Mureithi, Founder, Makao · Green Star Accredited Professional, ISAP, Engineers Australia member.
