Pointsbuild CPD Course for Australian Builders: Building Energy Efficient Structures: An Introduction

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1 Pointsbuild CPD Course for Australian Builders: Wednesday, 9 January 2013 Version 1.0 Prepared by: Michael Tomlinson Director, Pointsbuild Pty Ltd Michael.tomlinson@pointsbuild.com.au +61 (0) Course Author: Michael Plunkett Smartrate Pty Ltd Phone : Fax : Mobile : michael@smartrate.com.au 1

2 Table of Contents Acknowledgements... 3 Introduction... 3 Introduction... 3 Household Greenhouse Gas Emissions... 4 Australian Homes - Trends... 6 The Building Code of Australia... 8 Improving the Building Fabric - Reducing Energy Consumption... 9 About The Author: Smartrate

3 Acknowledgements MBA ABCB Yourhome Technical Manual ABCB Chapter 1 Introduction to Energy Efficiency Introduction This course is written as an overview of Energy Efficiency, and provides details on some of the key legislation and legal requirements that Builders and tradesmen are required to adhere to. 1. Overview Introduction Why do buildings today have to meet energy efficiency requirements that are mandatory under the Building Code of Australia (BCA), BASIX and local council Bylaws? Australians have been constructing residential, commercial and industrial buildings for over 200 years without having to meet these requirements. As the population increases, more pressure is placed on the community. The infrastructure that provides water, electricity and takes away our waste is required to expand at a pace that may not be sustainable. Governments of all levels are pressure to provide services to the community at a more efficient and cheaper cost. About 30 years, it became apparent that the growing population and the demands of this on the environment and resources, not only in Australia but across the world generally, was creating a world that in the future may not support us. A meeting of all nations was held in 1990 in Kyoto, Japan, and agreed to a plan that requires all nations to actively work to reduce the impact of our activities on the environment. Greenhouse gas emissions (GGE) are considered to be a major contributor to climate change. Energy production from the burning of coal, oil and gas is responsible for a large proportion of these emissions. 3

4 The 2008 Australian greenhouse gas emissions are estimated at 660 Mt of CO 2- e per annum. Australia has the highest per capita greenhouse gas emissions than any other nationality. Figure 1 Tonnes of CO 2 -e annual emission per capita About 1/3 of Australia s emissions are due to the production of electricity, mainly from coal fired power stations. In the 14 years to 2004 emissions have risen by 42% and are expected to increase to 56% by Emissions from the production of energy are projected to increase by 50% over the 1990 level and by 2020, 66% over the 1990 level. Emissions due to transport have risen by 23% and are expected to increase to 42% by These increases have resulted in government introducing regulations that aim to slow this increase and reduce the costs of building infrastructure. Energy used by buildings and households account for a large part of Australia s greenhouse gas emissions. Household Greenhouse Gas Emissions Greenhouse gas emissions from the household sector produces about one fifth of Australia s 4

5 total GGE. The average Australian home produces about 8-10 tonnes of CO 2 -e each year. Most of this is from energy use within the home, followed by private transport and the decay of household rubbish in landfill. The following relate to estimated energy use in Figure 2 Australian Residential CO2 emission share by end use On average, heating and cooling a house when it is too cold or hot outside requires the most energy, (90% heating, 10% cooling), followed by electrical appliances and water heating, as shown in the pie chart. 5

6 Figure 3 Australian Residential Energy share by end use The large amount of greenhouse gas emissions produced from the use of electrical appliances is due to the CO 2 emissions from generating electricity from coal. The relatively small amount of greenhouse gas emissions for heating and cooling is due to predominant use of gas for heating in NSW and Victoria, which produces much less emissions than electricity generated by burning coal. Australian Homes - Trends Australians are using more energy to keep their homes comfortable. In winter and colder times during the year, heating Australian homes accounts for 38% of energy consumption in the residential sector. Open fireplaces are disappearing and closed combustion heating is slowly being replaced by ducted gas heating with the largest share of heating a home. Where gas is not readily available reverse cycle air conditioning is providing heating at the lowest cost. The number of whole house heating systems in new houses is increasing. 6

7 Figure 4 Space heating energy by fuel type, DEWHA The number of houses with air-conditioning has started to climb since The current 2008 annual air-conditioner sales total about 1 million units, with 2/3 being installed in homes. The majority of these systems are split system reverse cycle air-conditioners, RRCC. Space cooling is responsible for about 3% of household energy use. Installation of air-conditioners has doubled in the last 10 years. 65% of houses have air-conditioners. Figure 5 Trends in space cooling energy by type, DEWHA The increasing affordability of heaters and air conditioners has enabled many home owners to install these appliances in their homes. This increase has lead to a surge in demand that has seen appliances made available to the Australian market that are of a low efficiency in converting energy used for heating or cooling a home. The demand for energy continues to trend upwards. 7

8 Over the last 18 years house floor area has increased by an average of 40% % chang e NS W Aus t % % Table 1 Changes in house floor area New house are getting bigger. The number of occupants per house is decreasing. The energy used per house is increasing. All of these trends have been recognised by government who since 2003 have introduced a series of regulations designed to slow the increase in energy consumption and reduce greenhouse gas emissions. The Building Code of Australia It is the high CO 2 emissions per capita in Australia that is largely due to the energy used to heat and cool our residential buildings that is addressed by the energy efficiency provisions of the Building Code of Australia. New commercial buildings are required to meet the requirements of Section J of Volume 1 of the Building Code of Australia. New homes are required to meet the requirements of Part 3.12 of Volume 2 of the Building Code of Australia. It is important to note that States and territories apply these regulations in different ways and have local requirements that amend and sometimes replace the requirements set out in the Building Code of Australia e.g. BASIX in NSW. We will look at the regulations around Australia in Chapter 10. 8

9 By making the minimum thermal performance requirement for a home to be 5 stars, the potential energy saving in heating and cooling the home is about 75% of the energy used to maintain similar comfort levels in an average home of the same size built before the building energy code was introduced. Improving the Building Fabric - Reducing Energy Consumption How do we reduce the energy consumption of a home? The answer is to have the home being comfortable to live in without having to turn on the heater or air conditioner. How do we do achieve this? Through having the building fabric (walls, roof, ceiling, floor and windows) of the home designed to perform well in its location so that when it is cold or hot outside it maintains the internal temperature of the home so it is comfortable for its occupants without turning on a heater or air conditioner. The degree of comfort that can be achieved is determined by the design and thermal properties of the building envelope. The use of correct insulation, thermal mass, floor to ground contact, good building sealing, orientation, good ventilation, the right type of glazing, are the major means by which comfort within buildings can be achieved in most Australian climates. Acknowledgements Figure 1 Dr Holger Willrath - The Thermal Performance of Buildings - Short Course Notes 9

10 Figure 2 Your Home Technical Manual - Department of Climate Change and Energy Efficiency Fourth Edition as amended published 2010 Figure 3 Your Home Technical Manual - Department of Climate Change and Energy Efficiency Fourth Edition as amended published 2010 Figure 4 Department of Environment Water Heritage and the Arts Figure 5 Department of Environment Water Heritage and the Arts Table 1 Course Notes Dr Holger Willrath - The Thermal Performance of Buildings - Short 10

11 About The Author: Smartrate SmartRate has experienced solid growth in the emerging field of thermal performance assessment by providing a range of cost effective solutions for small, medium and large builders on their client's projects to ensure they meet the energy efficiency requirements of the Building Code of Australia. These services extend to Owner Builders and for the renovation of existing homes. Established in 2007, SmartRate continues to set new standards in the delivery of innovative solutions and building on our reputation of excellent customer service. The management team is committed to working closely with you and your clients to achieve results that are not only cost effective, but exceed your expectations. For new residential construction, SmartRate performs energy ratings using BERSPro or Accurate software and provides a full compliance service including the preliminary assessment of projects during the initial design phases. For commercial projects, SmartRate provides a comprehensive report based on Section J of the Building Code of Australia. Our assessors are accredited with the Association of Building Sustainability Assessors (ABSA) and SmartRate's compliance Certification is acceptable to local Councils and Building Certifiers. SmartRate will provide home sustainability assessments in The team at SmartRate is headed by Michael Plunkett. MICHAEL PLUNKETT Michael has formal qualifications in Design and Architecture. He has over 30 years experience in the home building industry. He is the North Australia Director of ABSA and is an active member of the Housing Industry Association sitting on the Northern Australia Technical Services Committee. He is a respected trainer with the HIA and ABSA and delivers courses in BERSPro and Accurate around Australia each year Michael Plunkett Smartrate Pty Ltd Phone : Fax : Mobile : michael@smartrate.com.au 11