A grand design for energy efficiency has paid dividends for both the tenant and owner in a Christchurch office makeover.

When Goodman were given notice that IAG, the tenant of its 7000m2 property in Addington, was assessing its office options it came up with a sustainability sweetener.
Goodman created a blueprint to give the relatively new but underperforming property an energy efficiency upgrade, cutting IAG's carbon footprint, at the same time as it carried out earthquake strengthening work.

IAG liked the plan so much it renewed the lease early providing 10 years term certainty to their tenancy at 14 Show Place and both parties partnered together to achieve five star energy efficiency rating under the New Zealand energy performance rating programme NABERSNZ.

Commercial buildings are a significant power user, burning through 9 per cent of New Zealand's total energy use.


NABERSNZ uses a scale of 1 to 6 to benchmark office energy efficiency performance, with ratings carried out for whole buildings, just the tenancies or only the base building, including the common areas and services provided by the landlord.

Anna Lough, Goodman's Christchurch-based portfolio manager, says IAG were very much on board with gaining the whole building rating because it understood the sustainability underpinnings of NABERSNZ.

IAG's high-spec Auckland headquarters - the NZI building on Fanshawe St - included sustainability built into every feature when completed in 2009.

"[IAG] went and looked out in the market to see what they could get and no one was at the same place that we were at on really tailoring an energy efficient building for them.
"They wanted someone committed to achieving a high NABERSNZ rating."

Lifting the energy efficiency game in IAG's Christchurch office meant working floor-by-floor to strip and replace the services, fittings and furnishings, with only the lifts left untouched.

Built in 2005, the existing services in the two building campus were underperforming and struggling to cope with additional staff brought on to deal with the insurance aftermath of the Christchurch earthquakes.

Local engineers TM Consultants worked out where the biggest energy savings could be made, coming up with a solution that included a new VRF air-conditioning system, LED lighting on sensor controls, daylight harvesting, hot water heat pumps and a building management system (BMS).

Construction firm Hawkins, the main contractor, had only seven weeks to transform each 1200m2 floor while the majority of staff kept working on site.
Lough says it required a high level of cooperation and transparency from everyone involved in the project.


"I think one of the greatest things out of this is that we dealt with the challenges along the way openly and worked through them.

"There were a lot of variations to the contract, which is generally what happens when you're working within an existing building."

Photo / Supplied
Photo / Supplied

As-built plans never truly reflected what was constructed, says Lough, and the tight timetable nearly took a tumble when undetected earthquake damage was found on the final floor.

"Full credit to Hawkins to finishing the project on time."

Lough says the new, improved air conditioning system, which included heat recovery and fresh air mixing, provided the best energy efficiency returns, thanks to the energy focussed HVAC design.

Visual display units linked to the BMS providing real-time energy data usage in public areas have been key in promoting power savings to staff and visitors, she says.
The reward for IAG has been a 40 per cent saving on its energy bills.

This month the office also became the first in New Zealand to achieve a five star NABERSNZ whole building rating.

"I don't think we ever thought we'd be the first in New Zealand for a building rating," says Lough.

"We were actually targeting to be the first in Christchurch.

"That focus was there right from day dot around reducing the energy footprint and something that would impact on the wider environment in a promotional building for people to see."

It joins three highly rated Auckland buildings - 205 Queen St, Zurich House and WaterCare Services building in Newmarket - who have achieved four star ratings in the past month.

Alex Cutler, head of the New Zealand Green Building Council, which administer the rating on behalf of the Energy Efficiency and Conservation Authority (EECA), says it's too soon to get accurate New Zealand data on the effect NABERSNZ is having on office property values, but numbers from the Australian version of the scheme, NABERS, shows tenants there are willing to pay up to 8 per cent more to work in buildings with a high NABERS rating.

"It is attractive to tenants; it is attractive to investors."

Late last year Goodman sold IAG's Christchurch office for $33.2 million to Maori Hill Property Ltd.

Lough says she believes the money and effort spent on the building made it more saleable.

"It's a large building in a suburban office location but you're got a very well performing building.

"The greatest thing is it's got the capability of doing even better."
The rating, which sits alongside the Green Star rating tool for measuring sustainability during building design and construction, has been gathering momentum since introduced three years ago.

Around 1000 online energy performance self-assessments have been completed, with 41 certified ratings or re-ratings issued.

Cutler says the ratings don't have to be made public, but can provide a starting point to make improvements to a building or workplace.

"What we're seeing is portfolio owners rating all their buildings, getting the baseline and then deciding which buildings they are going to fine-tune or commission, and then which buildings they're going to upgrade," says Cutler.

"Clearly the ultimate outcome that we want is that a large proportion of building owners upgrade their buildings so they are using less energy."
EECA has a goal of 20 per cent of new commercial tenants seeking a NABERSNZ rating by 2018.

"I personally think a NABERSNZ rating is such a great tool in the sense that you actually have to work to achieve it, then maintain it and if you want to do better you have goals to optimise it," says Goodman's Lough.

"You've got that long-term commitment to good energy management."