Late last year the Queensland government released discussion papers around a new Queensland Building Plan. Consultation ends this month on reform proposals for both the residential and commercial building and development sector.
For the commercial building sector, there are few proposed measures recommended. One is to develop a non-mandatory development code for living roofs and living walls to improve thermal performance.
A draft non-mandatory maintenance code for energy efficiency in the ongoing operation of commercial buildings has also been developed and forms part of the current consultation documents.
The government has also proposed reassessing the value of rainwater tanks. These were at one point mandatory for all new commercial and residential buildings, but the requirement was dropped in 2013. It is also considering upgrading the water-efficiency requirement for commercial building toilets to require 4 Star WELS ratings instead of the current three stars.
Other topics the government is looking at include non-conforming products, the QBCC Home Warranty Scheme, security of payment, the use of Liveable Housing guidelines, a review of licensing and plumbing and drainage laws, certification and compliance, and a possible single state housing code.
Housing standards need improvement, exemptions need to be rethought
For new dwellings, proposals include adopting the national six star standard for new units, expanding the state’s optional credits scheme and revisiting rules around energy-efficient water heating.
For existing houses and units, strategies under consideration include producing consumer-focused information on energy efficiency and water efficiency and information on efficiency for industry practitioners.
While sustainability has been addressed in terms of both new and existing buildings, the proposed measures for new dwellings may fail to deliver substantial overall improvement, according to some.
Emma Thirkell, co-founder of the Tropical Green Building Network, says that while detached dwellings are required to meet the six star NatHERS standard under the National Construction Code, the state has an exemption through COAG for apartments, which allows an average of five star NatHERS to be deemed compliant.
Also, instead of the rating reflecting the performance of the building shell, an optional credit under the Queensland Development Code currently allows an outdoor patio with an insulated roof and an overhead fan to gain a star.
So effectively, the building shell may only deliver four star NatHERS, Ms Thirkell said.
Installing a solar PV system is also allowed a star under the optional credits scheme.
“We’ve always had an issue with the [patio] credit,” Ms Thirkell said.
The Queensland Development Codes introduced it when cost of constructing to a six star standard was considered a barrier to the industry delivering affordable dwellings.
It was also at a time when the industry was shifting towards increased concrete-based construction.
Ms Thirkell said
the TGB network had asked the Queensland building code officials and the Australian Building Codes Board to delete the credit.
Thermal lag a key concern
Thermal lag was one the most important things a building needed to achieve in the Queensland climate zones, Ms Thirkell said
“The cost of electricity is really hitting people renting hot boxes that need airconditioning.”
Thermal mass needs to be shaded, for example with plants or overhangs, so the sun doesn’t hit the building.
Where it does hit concrete walls, the thermal lag effect means the wall then radiates the heat back out just when the cooler evening air would be welcome.
Natural ventilation discussion missing
There is little mention in the proposals the government has formulated about the role of natural ventilation.
Ms Thirkell said this has recently been a topic for discussion in the industry.
One thing that has been holding back the concept of natural ventilation and how it affects the NatHERS rating is that the BERS PRO Queensland energy rating software was lacking climate files and windspeed files for the different climate zones in the tropics.
“It is a matter of [us] getting more files and wind speed data.”
That will then enable assessors and designers to better understand how buildings will naturally ventilate on a specific site, and this can then be reflected in the star ratings.
Rethinking star ratings may be needed
Ms Thirkell said the Queensland industry has gone “some way” towards incorporating natural ventilation. There are some cases where the entire building is climate-responsive, or where there are “pods” within the building that will rely on airconditioning, while other parts are naturally ventilated.
This may not necessarily produce a higher star rating, but it can be recognised by a designer, buyer or tenant as a more energy-efficient design.
Ms Thirkell said that particularly now, when buildings are getting excessive heat loads from rising temperatures, it is important to “get this right”.
“There is no point increasing the star rating until it can be delivered in a better way for different climate zones.”
She said that in many cases, even a home advertising itself as a 10 star home may not actually perform as one.
In these cases, the star rating as advertised is about enhancing the property value.
“The public are looking for energy efficiency. There was an old figure that it adds about 10 per cent to the value.”
Higher star ratings could lead to cost cutting
Ms Thirkell said if the government’s building plan involved mandatory higher star ratings, there could be a costly impact.
As a registered valuer, she said the rating was about rent and cashflow and increasing building values.
In an energy-efficient property, the tenants can afford to pay more rent. That means the owner can increase the rent, the increased value gets capitalised and the property yield increases as a reflection of future-proofing against further energy price rises.
In the discussion paper on the plan, it stated there was a split incentive in terms of improving energy efficiency. This is because it will potentially cost the developer and builder more, but only the owner or occupant will gain the benefit of reduced power bills.
Ms Thirkell said the developer should charge more for a better product. However, supply and demand can “skew the market”.
“If regulations force a developer’s margin to erode, that’s when they’ll cut corners, for example install poor quality solar PV.”
The same is true for commercial buildings, she said. An energy-efficient HVAC system might be installed to meet code requirements, but “there’s good ones and bad ones”.
There is also an issue with valuers, who Ms Thirkell said have not had practice standards modernised.
There are issues around depreciation of technology that mean a valuer is resistant to uplifting value where it has been added to a dwelling to gain the star rating. They are more likely to uplift the value for a pool, or other amenity uplifts such as views and location that are more permanent.
There are some other proposals in the discussion paper where Ms Thirkell thought there could be a smarter solution than what has been proposed.
In terms of laundries in apartment buildings, there is an either/or proposition around introducing external drying areas to reduce reliance on electric clothes dryers. On the con side, the paper notes it would need space, and would potentially be challenging for strata bodies to administer. On the pro side, people can have the choice of letting clothes dry naturally.
Ms Thirkell suggested the European approach of having a hanging rack in the laundry that is lowered when required could work.
Lobby groups come out against changes
Peak bodies, such as the Property Council, Master Builders Queensland and the Housing Industry Association, have been quick to come out against the proposed changes, which they say could increase costs by up to three per cent. Opposition has focused on proposed project bank accounts for projects over $1 million designed to protect subcontractors; and a move to take private certifier choice out of the hands of developers.
The consultation period finishes at the end of this month.
- Read the proposals and discussion paper here.