GREEN LIVING
Proposed amendments to the NCC 2022 energy efficiency provisions Dr Phillip Alviano Sustainability Advisor
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n 1 February 2019, energy ministers agreed to the Trajectory for Low Energy Buildings, a national plan for Australia to set a trajectory towards zero energy (and carbon) ready buildings. This report focussed on improving new buildings. NCC 2022 is part of this body of work. After a major stringency increase for commercial buildings in NCC 2019, building ministers directed the ABCB to develop enhanced residential energy efficiency provisions informed by the former COAG Energy Council’s Trajectory for Low Energy Buildings policy. This work supports the Australian Government’s commitment under the Paris Agreement to reduce greenhouse gas emissions and the National Energy Productivity Plan. These policies all focus on the role that buildings play in reducing emissions, improving energy productivity, reducing household energy bills, and helping to transition to the greater use of renewable energy and zero-emission vehicles. Below is an overview of the major changes that will be implemented in the NCC 2022.
Summary of major changes Stringency increase the Star Rating Measure Increase thermal performance from the current level, equivalent to 6 Star NatHERS, to the equivalent of 7 Stars.
50 | Master Builders Victoria
What’s likely to be involved? Higher window and glazing performance. Increases in ceiling and wall insulation R-values. Restrictions on wall and roof colours. Changes to structural floor systems (insulated slabs or sub-floor insulation. Whole of home energy use requirements added As well as meeting the 7-Star requirement, new houses and single occupancy units (SOU) will need to meet a collective energy use budget for heating and cooling systems, hot water, lighting and swimming pool and spa pumps (where fitted). Measure Whole of home annual energy use requirements. Differences between Class 1 and Class 2 buildings. What’s likely to be involved? Introduction of a collective energy use budget for; • Air conditioning and heating systems. • Hot water systems. • Lighting. • Swimming pool and spa pumps. Ability to trade between the efficiency of systems for annual energy use budget. Onsite renewables may be installed to offset the energy consumption of the equipment but not the building fabric. The ABCB will provide a simple whole-of-home calculator to assist in quickly determining the requirements. The NatHERS Administrator is also expanding NatHERS beyond thermal comfort to incorporate whole-of-home requirements to align with the proposed NCC 2022 provisions. This will allow the whole-home assessment to be completed as part of the energy rating. New deemed to satisfy elemental provisions (Class 2) Measure New set of measures deemed to satisfy introductory provisions for Class 2
buildings. What’s likely to be involved? • The whole of the apartment building will need to achieve an average 7-Stars with no apartment permitted to be less than 6-Stars (under NCC 2019 6-Star average and no apartment less than 5-Stars. • Developing new elemental DTS provisions for Class 2 buildings set at 7-Star equivalence (this will provide a second pathway for apartments to verify compliance after this option was removed in NCC 2010). • Developing a new verification using the reference building method for Class 2 buildings. • Introducing new requirements for thermal bridging and steel framing. Note, the thermal bridging mitigation measures proposed for NCC 2022 do not seek to eliminate thermal bridging by all framing. Instead, it proposes to reduce the thermal bridging of steel frames, so the total R-Value of an element with steel framing is: • • No less than 95 per cent of that for a timber-framed element for insulation R-Values of R3.0 or less. • • No less than 90 per cent of that for a timber-framed element for insulation R-Values above R3.0. This differential approach reflects the diminishing returns of insulation at higher R-Values. Retrofit onsite renewables & vehicle charging Measure New provisions designed to allow easy retrofit of onsite renewable and electric vehicle charging equipment for Class 2 to 9 Buildings. What’s likely to be involved? New provisions are designed for ‘solar ready’ zones for potential future electric vehicle charging equipment installation for Class 2 to 9 buildings. New provisions are being proposed to
Volume 76 Issue 04
