Some links on this page are affiliate links: if you buy through them we may earn a commission, at no extra cost to you.
Council House 2 (CH2) is a City of Melbourne office building completed in 2006, recognised for its integrated environmental design and 6 Star Green Star ratings for both Office Design v1 and Office As Built v1. It is a landmark in Australian sustainable construction, but the available evidence does not establish that it is currently the country’s greenest office building in a like-for-like comparison. Its lasting significance is how shading, ventilation, thermal mass, cooling, water reuse and onsite energy systems were brought together in one project.
What is Council House 2?
CH2 stands for Council House 2, a City of Melbourne office building at 218–242 Little Collins Street in Melbourne. Completed in 2006, it was developed by the City of Melbourne with DesignInc; Hansen Yuncken identifies itself as the main contractor. The project is widely recognised as an early Australian example of a high-performance sustainable office building.
As an Amazon Associate I earn from qualifying purchases.
Quick wins for a faster PC:
Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →The Green Building Council of Australia (GBCA) records the building as 6 Star Green Star – Office Design v1 and 6 Star Green Star – Office As Built v1. These are two distinct project credentials: one concerns design, and the other records the as-built project. Hansen Yuncken describes CH2 as Australia’s first commercial office building to receive six-star Green Star ratings for both. DesignInc calls it the first commercial project awarded a 6 Star Green Star rating. Those are notable historical milestones, not proof of a present-day national ranking.
Published area figures use different measures. DesignInc gives the project’s scale as 12,500 m², while the GBCA project record lists a net lettable area of 9,373 m² and ten storeys. These figures should not be treated as competing measurements of the same thing: net lettable area is a defined portion of a building, while a project-scale figure may refer to a broader area. The sources do not provide a single reconciled area measure.
Popular on Amazon
- Ergonomically Designed: Work in tight areas with a compact design that gets into tough spots
- Both tools are designed to fit into difficult to reach spaces
- Complete a wide range of applications with a high-performance motor that delivers up to 300 UWO, and an impact driver delivering up to 1,400 in-lbs of torque
- Both the DEWALT impact driver and drill driver feature integrated LED work lights with a convenient 20-second delay, ensuring enhanced visibility in dimly lit or challenging work areas
- One-Handed Loading - Keep one hand free with a 1/4 in. hex chuck that accepts 1 in. bit tips
For a construction audience, CH2 is useful less as a catalogue of unusual equipment than as an example of systems integration. The building’s environmental strategy responds to Melbourne’s sun, wind and temperature variation by combining design choices that influence heat gain, daylight, ventilation, cooling, water demand and energy supply.
How does Council House 2 save energy and water?
CH2 uses a combination of passive design and building services rather than relying on a single technology. Shading, ventilation and thermal mass shape the building’s heating and cooling needs; water harvesting, treatment and reuse reduce dependence on potable mains water; and onsite generation systems contribute to energy supply.
Shading, daylight and the building fabric
Recycled-timber screens shade the western façade, where sun exposure can contribute to heat gain. The screens are part of the building’s response to local conditions, not an isolated decorative feature. Tapered ventilation ducts are also described as bringing daylight into the building. Together, façade shading and daylight access illustrate how enclosure design can address both solar exposure and interior conditions.
Concrete floor mass contributes to heating and cooling. In a building that also uses ventilation and night purging, thermal mass forms part of a wider strategy: the building fabric can store and release heat as indoor conditions change. The sources describe these elements as components of the design, but do not supply a current, independently audited breakdown of how much energy each one saves in operation.
Ventilation and cooling
CH2 is described as using fresh-air ventilation, chilled ceilings or beams, roof turbines and night purging. Night purging uses ventilation to remove heat, while roof turbines support air extraction. The building’s systems are intended to work alongside the shaded façade and concrete mass, rather than substituting for them.
Also popular on Amazon
- Valued Carpenter Pencil Set: You will get 2 pcs solid carpenter pencils with 26 piece 2.8 mm refills, 1 replaceable sharpener, 1 plastic storage box.The complete carpenter pencils combination allows you to finish your work faster and more easily
- Deep Hole Marker Pencil: The deep-hole construction pencils adopts 45mm elongated tip design, which is more convenient to mark in the small hole or in other tight areas that other carpenter markers cannot reach
- Carpenter Pencils with Sharpener: The sharpener is screwed into the top of the work pencil, which won't get lost either. Built-in pencil sharpener that keep the lead with pointed and smooth to Improves line of sight in fine work
- Stronger Solid Lead: This work pencil is matched with a 2.8 mm thick lead , which is much thicker and stronger during the drawing process of construction work, it will not break or damage easily
- Marks on Various Surfaces: 3 colors solid construction pencil can marks on various surfaces,such as metal, plastic, wood, paper etc. Ideals for woodworkers, contractors, craftsmen, builders, merchants and masons
The National Heart Foundation of Australia’s Healthy Active by Design case study describes the project’s ventilation and cooling approach. DesignInc’s project page attributes a productivity claim to two full air changes per day. That reported claim should be read as a project spokesperson’s account, not evidence that a particular ventilation rate will produce the same health or productivity effect in other buildings.
Water treatment and reuse
The GBCA record lists water-efficient fittings, sub-metering, a blackwater-treatment plant for non-potable demand, gardens and sprinkler-water reclamation. The wider project descriptions also refer to water harvesting and treatment, sewer mining and shower towers. These features address different points in the water cycle: reducing demand, treating or reclaiming water, and using non-potable sources where suitable.
That distinction matters when interpreting the project’s water-saving claims. “Mains water,” “potable mains water” and “water consumption” are not necessarily interchangeable metrics, and a reported reduction depends on its baseline and accounting method. CH2’s cited figures therefore need to stay attached to their original publishers and comparison contexts.
Onsite energy
Project descriptions identify photovoltaic cells, wind turbines, solar hot water and cogeneration among CH2’s energy systems. These components form part of the building’s onsite energy approach, alongside measures intended to manage demand. The available records do not provide a current energy balance showing how much each source generates today, nor a current independent operational audit.
What do the published savings figures actually show?
Different sources report substantial savings, but their figures use different metrics, baselines and reporting contexts. They are best understood as claims reported by the named source—not combined into one independently verified performance result for CH2 today.
Also popular on Amazon
- 【Great Compatibility】This Katerk 1/4 inch hex shank bit holder is specifically designed for 1/4 inch hex shank drill bits. It's compatible with most 1/4 fast hex handles, hex sockets, various electric screwdrivers, and handheld screwdrivers. The bit holder makes it a valuable addition for any handyman.
- 【Secure and Safe】Built with a secure backup nut design, each drill bit holder securely locks onto your bits, ensuring they stay firmly in place. Additionally, our bit holder incorporates a high-quality steel ball rolling design that holds up to several kilograms of weight, ensuring your various drill bits don't fall off.
- 【Easy One-Handed Operation】The bit holder for impact driver allows you to change bits single-handedly, simplifying your workflow. Its multi-color design further allows for quick identification of the drill bit you need.
- 【Compact and Convenient】Thanks to its compact size, this 1/4 inch bit holder is easy to carry around. The bit holder allows for easy attachment to various tools, making this a convenient addition to your construction accessories. The Katerk bit holder is cast from high-quality alloy material, promising a long product lifespan. Despite its rugged strength, the bit holder remains lightweight, making it portable.
- 【Cool Christmas Gift For Men Stocking Stuffers】 This screwdriver bit holder, driver bit holder, impact bit holder, can be given as a gift to your loved one, especially for anyone involved in construction or electrical work. It's a must-have for stocking stuffers for men and women, tools gifts for dad, tech gadgets for men, gifts for dad, gifts for him, gifts for husband, gifts for boyfriend, cool gadgets for men, and cool gifts for dad.
| Source and context | Reported figure | How to interpret it |
|---|---|---|
| Australian Government case study, October 2006 | 72% expected savings on mains-water consumption; 80% expected reduction in sewer emissions | Expected outcomes compared with an existing Council House of similar size, as stated in the case study. |
| National Heart Foundation of Australia, Healthy Active by Design case study | 85% less energy, 87% less gas and 72% less potable mains water than the council’s previous building; 60% less CO₂ than a five-star base-building rating under the Australian Building Greenhouse Rating Scheme | Figures reported on the case-study page; its comparisons use different measures and baselines. |
| DesignInc project page | 80% reduction in power consumption and 75% reduction in water consumption | Project-page claims, with no measurement period or detailed baseline specified on the page. |
| Hansen Yuncken project page | More than 85% of construction-site waste recycled | A construction-phase claim, separate from operational energy or water performance. |
These numbers should not be averaged or presented as a single savings rate. For example, power consumption and energy use may refer to different measures; the stated water figures refer variously to mains, potable mains or water consumption; and one comparison is explicitly against the council’s previous building while another is against a building-rating baseline. The source set does not establish a shared measurement period or a common independent verification method.
For a project team assessing a new building, the practical lesson is to define the baseline, metric, boundary and measurement period before announcing a target or result. A reduction against a previous building is not directly equivalent to a reduction against a rating benchmark; a design-stage forecast is not the same as a post-occupancy result.
What did the project claim about staff health and productivity?
DesignInc’s project page quotes Rob Adams, Director of City Design and Projects at the City of Melbourne, saying: “Productivity studies show that the two full air changes per day have led to a 10.9 per cent increase in staff health and productivity. That’s a saving of around $2 million a year. When people ask about the cost of this technology, I say, the real question should be: how can you afford not to design this way?”
This is an attributed project statement presented by DesignInc. The page does not identify the publication year or provide the underlying studies’ methods, so the 10.9% figure and the associated annual saving should not be treated as a generally established causal result or a forecast for another building. Indoor air quality and occupant outcomes can be important project objectives, but evaluating them requires clear definitions, suitable comparison groups and documented methods.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →DesignInc also quotes Stephen Webb, Design Consultant and former Design Director at DesignInc Melbourne: “More than a building, CH2 is a working ecosystem. We collaborated closely with City of Melbourne to create something we believe is truly remarkable.” That description captures the project’s integrated ambition, while the performance figures still require careful attribution.
Also popular on Amazon
- Toolwiz 17-inch magnetic sweeper maintaining a load capacity of up to 8.8 pounds provides a perfect solution to the problem of clearing small ferrous metal objects, such as nails, tacks, bolts, and metal shavings from workshops or garage floors.
- Convenient and portable：17” is good for home, small workshop, or small yard as it is space-saving and more reachable for narrow areas. Perfect for collecting nails or small parts in the car, under the table, and in other nooks or crannies.
- Upgraded Handle Design: The handle features a sturdy, non-telescopic design to completely prevent slipping during use. By simply adding or removing the extension poles, the height can be adjusted to 3 different lengths: 18.9" (48 cm), 32.5" (82.5 cm), and 42.5" (108 cm) from ground to top. This customizable height helps prevent back bending and muscle strain, making your cleaning tasks effortless
- Flexible wheels: Upgrade wheel screws to avoid being too tight to spin or too loose. More comfortable 3-inch rubber wheels roll smoothly on carpet, grass, concrete, and hardwood floors. Just push and pull this rolling magnet-sweeper to pick up metal nails easily.
- Lightweight materials: The magnetic nail sweeper's compact and lightweight design makes the sweeping can be done anywhere you want, Push or pull it under the furniture, passing through the workshop floor, driveway, mud, grass, and gravel.
What did CH2 cost, and what was the expected payback?
Historical sources reported different estimates for the additional cost of CH2’s sustainability features. An Australian Government case study from October 2006 said those features were expected to add 38% to base cost, with a ten-year payback through lower operating costs. An ABC Radio National report dated 31 August 2007 described the sustainability features as adding 22%, or A$11.3 million, to construction cost, and said the council hoped to recover the amount within a decade.
Those figures should not be reconciled into a definitive project cost without further evidence. They are historical estimates from different sources and reporting contexts, not a current cost assessment. The projected payback is also an expectation, not proof in the cited material that the investment was recovered on schedule. For contemporary planning, lifecycle cost analysis should make capital-cost assumptions, operating-cost baselines, maintenance, replacement cycles and the evaluation period explicit.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Why is CH2 considered a landmark, rather than simply “Australia’s greenest”?
CH2’s landmark status is supported by the project record: it was completed in 2006, received six-star Green Star ratings for both design and as-built, and brought together multiple environmental systems in a prominent city office building. But “Australia’s greenest office building” is a superlative that requires a current, like-for-like comparison across relevant buildings. The reviewed sources do not provide that comparison.
Recommended Free Tools
A credible ranking would need to compare the same kinds of evidence: certification scheme and version; design, as-built or operational rating; energy and water metrics with their baselines; measurement periods and independent verification; occupant outcomes; construction and embodied impacts; and lifecycle costs. CH2’s historical achievements remain significant without claiming that it holds a current national title.
That distinction is especially useful for construction professionals. A high rating can document achievement under a particular scheme and version, while operational outcomes depend on how the building performs after handover and how those outcomes are measured. A strong case study can inform design decisions, but it is not a substitute for current project-specific data.
Also popular on Amazon
- APPLY TO MOST DRILLS : 6 pieces screw extractors work with any drill and all the screw size or bolt (3-12mm), These extractor tools are used to reverse the damaged screw counterclockwise until it is released
- The DIY Tools for Men-Men won't know they need screw extractor set until they have one! This screw extractor set is GIFTS WRAP AVAILABLE, can be gifted to your loved ones as it reflects a fresh trend with fun and practical. Amazing and Unique tool gifts for men women. The must have stocking stuffers for men, gifts for dad, husband, father, him, guy teens, adult, Boyfriend, son on Birthdays, Christmas, Fathers Day or anniversary. Perfect Holiday Gifts Guide
- HIGH QUALITY - This damaged screw remover tool kit is made from High-Speed Steel H.S.S 4341# , which have high hardness of 63hrc, it's durable and easily to remove any damaged screws.
- EASY TO USE: Just two simple steps to get the job done - drill a hole with a cutting size using the right size screw extractor and easily remove the screw or bolt using the removal tool Hardness 63-65HRC: Titanium hardened steel material, more durable than most screw extractors on the market, better hardness and durability than others, buy with confidence and complete peace of mind
- Cool Gadgets for Men Dad Christmas Birthday Gifts for Men and Women - Men won't know they need screw extractor sets until they have one! Every screw has the potential to rust and break, which can create a situation where it cannot be removed. Owning it, there will be no anxiety about rusty screws. This screw extractor set is GIFTS WRAP AVAILABLE, can be gifted to your loved ones as it reflects a fresh trend with fun and practical. Amazing and unique tool gifts for men women. A must have stocking stuffer for men on birthdays, Christmas, Father's Day or anniversaries, a gifts for dads, husbands, fathers, him, adults, boyfriends, sons. The best and most practical and surprising Christmas gifts
What can designers and builders learn from CH2?
CH2’s most transferable lesson is to coordinate architectural decisions and building services early. Shading, daylight, ventilation, thermal mass and cooling influence overlapping conditions; treating each as a standalone feature risks missing the interactions that make an integrated strategy work.
- Start with local conditions. CH2’s design responds to Melbourne’s sun, wind and temperature variation. The right façade, ventilation and thermal strategy for another site depends on its climate, orientation and use.
- Connect passive measures to services. The building combines shading and concrete mass with ventilation, chilled ceilings or beams, roof extraction and night purging. The documented project supports a coordinated approach, not a claim that any one component guarantees a particular saving.
- Plan water by source and end use. Water-efficient fittings, treatment, reclamation and non-potable demand management address different opportunities. Define which water streams are counted and what uses they serve.
- Make targets auditable. Record the baseline, metric, system boundary and period for each target. Separate expected design outcomes from results measured after occupation.
- Consider construction impacts alongside operations. Hansen Yuncken reports that more than 85% of construction-site waste was recycled. That construction claim complements, but does not replace, operational energy and water reporting.
As Stephen Webb’s comment on DesignInc’s page suggests, the project team saw CH2 as an ecosystem. For today’s project teams, the practical test of that idea is not whether a building repeats CH2’s named systems, but whether its design choices, services, commissioning and performance reporting work together for the site and occupants.
Free tools Windows power users keep installed
One-click scans. No signup required.
Sources and reporting limits
The project details and attributed claims above draw on the DesignInc CH2 project page, the GBCA’s Sustainable Melbourne Walking Tour record, the Australian Government’s October 2006 CH2 case study, the National Heart Foundation of Australia’s Healthy Active by Design case study, Hansen Yuncken’s CH2 project page and ABC Radio National’s 2007 report. Several project pages are undated, and the GBCA record is a historical PDF. The evidence supports describing CH2 as a landmark, but it does not supply a current independent operational audit or a contemporary national comparison.
Frequently Asked Questions
What does 6 Star Green Star – Office As Built v1 mean?
It identifies CH2’s as-built certification under the Office v1 Green Star rating tool, rather than a current operational score. The GBCA record separately lists an Office Design v1 rating, so the two credentials document different project stages.
Why do published CH2 area figures differ?
DesignInc gives a project scale of 12,500 m², while the GBCA lists 9,373 m² as net lettable area. Since the latter measures lettable space specifically, the figures use different area definitions and should be quoted with their source and measure.
Does CH2’s six-star rating prove it is Australia’s greenest office today?
No. The rating records an achievement under a named scheme and version, but a current national superlative would require comparable contemporary evidence across buildings, including operational data and consistent baselines.
Why do sources give different estimates for CH2’s added construction cost?
The Australian Government’s 2006 case study reported a 38% expected addition to base cost, while ABC Radio National reported a 22% estimate, or A$11.3 million, in 2007. The sources provide different historical estimates and do not establish a reconciled final cost.
