 Welcome to using the energy efficiency provisions in NCC Volume 2. The focus of this presentation is the energy efficiency provisions in NCC Volume 2 and the related housing provisions. This presentation has a practical focus and looks in detail at the specific performance requirements. The DTS provisions and assessment methods for energy efficiency that apply to Class 1 and Class 10 buildings. What you will learn. Energy efficiency performance requirements in Volume 2. Compliance solutions for energy efficiency in Volume 2. House energy ratings. Assessment methods for energy efficiency in Volume 2. Energy efficiency in the ABCB housing provisions. Other useful resources. Energy efficiency in NCC Volume 2. Section H. The two performance requirements in Part H6 of NCC Volume 2 reflect the key concerns for energy efficiency in Volume 2 of the NCC. H6 P1. Thermal performance. This relates to the building's ability to maintain a comfortable internal temperature for occupants while using as little energy as possible to do so. By achieving good thermal performance, the building will meet objectives to improve occupant health and amenity. H6 P2. Energy usage. The key objective of this requirement is to reduce energy consumption, energy peak demand and reduce greenhouse gas emissions. The DTS provisions in Part H6 also reflect these key objectives. It links to Section 13 of the ABCB Housing Provision Standard for Elemental Pathway. Section 13 contains seven parts and is discussed in more detail later in this module. Performance solution. They should remember that they don't have to use the DTS provisions but can develop a performance solution instead. Or they can use a combination of a DTS solution and a performance solution. Verification methods. Two verification methods exist. H6 V2, verification using a reference building. You can use this verification method to comply with H6 P1. This method requires you to compare the performance of the proposed building with a reference building that meets the DTS provisions. H6 V3, verification of building envelope sealing. This method can be used to meet the building sealing part of H6 P1. It tests the air leakiness of the building. Or in other words, how well the external building envelope is sealed by using what is known as the blower door test. In technical terms, the method requires the building envelope sealing to achieve air permeability of not more than 10 cubic metres an hour metre squared at 50 PA pressure when tested in accordance with AS and ZS ISO 9972 method 1. Specifications. Specification 42, house energy rating software. This specification sets out the requirements for satisfying H6 P1 and H6 P2. Using the NATAS DTS energy rating software pathway. Specification 44 calculation of heating load limit, cooling load limit and thermal energy load limit. This specification contains the method of calculating the heating load limit, cooling load limit and thermal energy load limit for compliance with H6 P1 and J1 P2, volume 1. What are the energy efficiency performance requirements? In NCC volume 2. The key objective of the NCC volume 2 energy efficiency provisions is to reduce the greenhouse gas emissions that a building produces over its lifetime. An additional benefit of the provisions is that an energy efficient home can be more comfortable to live in and cheaper to operate. The energy efficiency provisions in NCC volume 2 addresses two aspects. The thermal performance of the building envelope, that is the ease with which heat flows into and out of the building. It is assumed that improving the thermal performance of the building fabric will reduce the need for artificial heating and cooling. As heating and cooling are key contributors to the total energy use of a typical Australian home. Improving the building's thermal performance should reduce its energy use and therefore should reduce greenhouse gas emissions over the life of the building. NATAS, 7 star equivalent. The efficiency of the domestic services, that is how much energy is used to run things like air conditioning, heating and lighting and to heat water, showers, etc. The source of the energy used, particularly the use of renewable energy, reclaimed energy or low greenhouse gas intensity fuels. Variations exist for NSW, Tasmania and the Northern Territory. If the trainees live and work in these states, territory, they need to be aware of these variations. However, they should understand that the aim of the provisions is the same in all states and territories, i.e. to reduce greenhouse gas emissions from housing in Australia. DTS Pathways for Compliance. In section H of volume 2, some DTS provisions contain more than one pathway for compliance. Usually, the first of these pathways will be by reference to a relevant Australian standard or other similar reference document. The second will be by referencing a part or section of the ABCB Housing Provisions Standard, a.k.a. the Housing Provisions. The fire safety related DTS provisions in volume 2 are found in Part H6, Energy Efficiency. You will find they contain references to the Housing Provisions. The Housing Provisions contain the majority of the DTS provisions for volume 2, including those relevant to Energy Efficiency. If a DTS provision in volume 2 does not reference the Housing Provisions, then the Housing Provisions cannot be used for that provision. The Housing Provisions contains DTS provisions considered to be acceptable forms of construction that meet the requirements for complying with Parts H1 to H8 of volume 2. That is, they comply with performance requirements listed in Parts H1 to H8 of volume 2. You can click on the small red volume 2 logo to bring up the connector arrow between the volume 2 and Housing Provisions boxes to illustrate the relationship between the two documents. There is no need to adopt any particular options set out in the Housing Provisions if it is preferred to meet the performance requirements in another way. It will then be up to the appropriate authority to decide if the performance requirements have been met. The Housing Provisions must be applied in line with each of the following. Any conditions on the Housing Provisions set out in the DTS provisions of volume 2 were referenced and the scope clause at the start of each section of the Housing Provisions. Remember that you can also choose to develop a performance solution to meet some or all of the applicable performance requirements. In this case, it is most important to discuss your proposed solution with the appropriate authority to determine which assessment methods will be acceptable. It might also be useful to get advice from an experienced fire safety engineer. Part H6, H6-D2 in volume 2 outlines two DTS pathways for complying with the energy efficiency performance requirements. The pathway 1 is to use the House Energy Rating Software, NATAS, by applying specification 42 to achieve the heating and cooling loads. Now to quivel an energy usage and other energy saving features such as thermal brakes, compensation for a loss of sealing insulation, floor edge insulation and building sealing. The pathway 2 is to apply the elemental provisions by using section 13 of the ABCB Housing Provisions standard, Housing Provisions, to satisfy all the detailed provisions. As you can see, when you bring up the section 13, Label and Associated Dot Points, these provisions deal with different elements of the building, including building fabric, i.e. the external envelope, external glazing, building sealing, sealing fans, whole of home energy, usage and services. How can we comply with the energy efficiency performance requirements of NCC Volume 2? All options for compliance must be supported with suitable evidence and or documentation to demonstrate that compliance has been achieved and assessed and approved by the approval authority. If they want to, a designer or builder can choose to use a performance solution instead of the DTS provisions for any aspect of the performance requirements. For example, they could comply with a different standard such as the passive-HAS standard and present the approval authority with evidence that this meets or exceeds the thermal performance and building sealing provisions of the NCC. Can we use the reference building verification method to demonstrate that a performance solution will meet or exceed requirements? Regardless of the solution used, appropriate and sufficient evidence must be provided to the approval authority to allow them to assess whether the solution meets the performance requirements. Application of Part H6, NATAS Energy Rating Question 1. What minimum NATAS energy rating is required for most houses and DTS provisions in NCC Volume 2? Answer 1. Generally 7 stars. Derived using a NATAS-approved version of house energy rating software. Question 2. When can this 7-star requirement be varied? Answer 2. Buildings in climate zones 1 and 2, either 6.5 or 6 stars, depending on whether 1B or 1C applies. If they have a covered outdoor area that meets the specified requirements, e.g. has a solid roof that meets the specified total R value and has a permanently installed ceiling fan, if a state or territory variation exists that varies this requirement, refer to earlier slide. Question 3. Where can you find the required heating and cooling loads for different climate zones? Answer 3. In the ABCB Standard for NATAS Heating and Cooling Load Limits, this can be found on the ABCB website. NATAS Energy Rating, NATAS Assessment One way of meeting performance requirement H6P1 is to do a house energy rating, which assesses the thermal performance of the building fabric as a whole. All buildings assessed in this way must achieve a minimum 7-star rating from a rating system that runs from 0 to 10 stars. 0 stars means that the building has little to no energy efficiency features or savings, while 10 stars means that the building should not need additional energy to heat it or to cool it to a comfortable temperature. There is a concession in the NCC for buildings in NCC climate zones 1 and 2, which have hot and humid weather. These concessions allow a building to rate only 6 or 6.5 stars, provided that it has a covered outdoor living area where the covering meets minimum total R-value requirements and there is a permanent ceiling fan installed. Individual Heating and Cooling Loads Houses in some climate zones must also meet individual cooling and heating load limits, specific to the climate zone. This applies in mixed climate zones where both heating and cooling are required at different times of the year. It doesn't apply in climates that are dominated by hot or cold weather. For example, the climate zones in much of the Northern Territory, Tasmania and some zones in Queensland and Western Australia. Where there are specific heating and cooling loads, it means that a building must meet energy efficiency requirements for both heating and cooling, as well as meeting the overall energy efficiency target. So, a house in a mixed climate zone, for example in Canberra or Adelaide, might perform really, really well in winter, i.e. it has a very low heating load, while performing badly in summer, i.e. having a high cooling load. When the two loads are added together, the building might remain under the total required for a 7 star overall rating. But if the building exceeds the cooling load limit, it cannot be given a 7 star NATAS rating. This means that it would not comply with the building fabric efficiency requirements of H6P1. The building designer would have to change the design to reduce the use of energy to cool the building before the building could achieve a 7 star rating. The actual heating loads, cooling loads and overall loads that a building must meet vary by climate zone. This is because it is not reasonable, for example, to expect a house in a cooler climate zone, for example in Canberra, to use the same energy for heating in winter as a house in a milder climate zone, say in Brisbane. This means that a house in Canberra with a 7 star rating will use more energy for heating than a similar house in Brisbane, which also receives a 7 star rating. The ABC standard for NATAS heating and cooling load limits contains the separate heating and cooling load limits that apply to the design and construction of dwellings that are assessed using the NCC's energy rating assessment pathway. NATAS assessment. Only a rating done using a NATAS accredited software tool is acceptable. NATAS assessment can be complex, as a lot of building data needs to be entered correctly into the software. It must be done by a qualified accredited assessor using the building plans and details that will be submitted for building approval. The NATAS assessor provides a formal certificate of the star rating and stamps the building plans. Once a star rating has been completed for the building and the plans have been stamped, salient details of the plans cannot be changed without doing another rating. Some designers and builders will work with the NATAS assessor early in the design process to ensure that a new building will achieve a high energy efficiency star rating, particularly as more people are prepared to pay a premium for good energy efficiency. The NATAS software can be used too. Identify the elements of the building's design that are contributing to poor energy efficiency and a poor star rating. For example, the software can identify that breaks in the building envelope are increasing the heating load. For example, from exhaust fans or downlights. Or it might identify that large unshaded windows on the west of the building are increasing the cooling load. Tweak a building's design and construction features to improve the energy efficiency and therefore the star rating. If this is done early in the design process, then big improvements can be made to energy efficiency relatively easily and cheaply. For example, there is a misconception that double glazing is always the solution for achieving good thermal performance, particularly in mixed climates. And double glazing can be expensive. But in fact, altering the size of windows on different orientations and changing the shading on windows can go a long way towards improving a building's energy efficiency and therefore its star rating. For example, increasing the width of the eaves on the east and west of a building to provide shade over glazing can help to reduce solar gain in summer. An experienced NATAS assessor can identify the key elements contributing to a poor star rating and suggest less expensive improvements that can help to increase the rating. Other requirements. A NATAS rating is not sufficient on its own to comply with H6P1 and H6P2. To meet these performance requirements, the building also has to comply with other common parts of the DTS provisions, such as part 13.5 of the housing provisions for building ceiling, H6P1, and part 13.7 of the housing provisions for services, H6P2. Later slides contain activities to work through some of the details of these other DTS provisions for complying with H6P2. Points of potential confusion. When the NCC references a climate zone, it is referring to one of the eight climate zones described in Schedule 1 definitions in the NCC. The climate zones used in the NATAS software are not the same as the NCC climate zones. NATAS software uses a more detailed set of climate zones, 69 as at early 2000 and 21. That recognises a whole set of climate differences, including wind patterns. This doesn't change the assessment of which NCC climate zone a building falls into. Energy efficiency star ratings similar to NATAS ratings are used for other purposes in some states' territories. For example, the ACT requires buildings being bought and sold to advertise an energy efficiency rating known as an EER. If the building is brand new and has never been occupied, a NATAS rating can be used as the EER. This is usually the NATAS rating that the building received in order to gain building approval. If the building has been occupied, however, the EER is not quite the same as the NATAS rating. It is done using different software and rates houses on a scale of 1 to 6 stars only. An existing house that receives a 6 star EER rating would not necessarily receive a 7 star NATAS star rating. If a trainee is working in the ACT or nearby, they need to understand the difference between these two rating schemes. An EER is simpler and cheaper than a NATAS assessment, but you can't use an EER star rating to apply for building approval for a new building or renovations. New South Wales uses a similar rating system called Basics. This tool provides New South Wales homes with the same level of performance as NATAS 7 star. What are the DTS provisions in section 13, and what is the efficiency of the housing provisions? Part 13.2, Building Fabric The intent of the building fabric provisions is to ensure that the building envelope is an effective means of resisting unwanted heat flow. Heat always flows from a warmer space to a cooler space, so heat flow may be either predominantly into or out of a building depending on the climate zone. Insulation can assist in limiting heat flow. A thermally efficient building envelope has energy as needed to artificially heat or cool internal spaces. Thermal insulation can be reflective or bulk insulation. It can be added to the elements of the building fabric to achieve the required total R value specified in the housing provisions. Walls. Requirements for total R value of external walls are tailored for different climate zones, and the requirements are different for both high mass and lightweight external walls, e.g. cavity masonry or metal sheet on timber stud construction. Floors. Insulation requirements for floors also vary for floor types, e.g. suspended floors on ground slabs. Bathrooms. There is a concession for built-in heating or cooling that is solely used in a bathroom or amenity area. Roof lights. There are also DTS provisions for roof lights which are defined in the NCC as a skylight or window installed in a roof to permit natural light to enter the room below and which is at an angle between 0 and 70 degrees measured from the horizontal plane. From a thermal design perspective, a roof light must be protected to reduce the heat loss or gain. Part 13.3. External Glazing. The intent of Part 13.3 is to control the amount of heat transferring or leaving a building through glazing. The means by which the heat enters a room or leaves a room through glazing are conduction, solar radiation and air infiltration. Conduction and solar radiation are addressed in clauses 13.3.2 and 13.3.3 while infiltration is covered under the ceiling requirements in Part 13.4. There are five key factors affecting heat transfer which are location of the building, area of glazing, degree of sun exposure, orientation and shading. If the building is air conditioned the type of frame and glass used as this determines the total system U-value and solar heat gain coefficient for the glazing system. The treatment of glazing to limit unwanted heat gain or loss is one of the most important aspects of the energy efficiency requirements in the housing provisions. Glazing design is assessed based on conductance and solar heat gain. The housing provisions set separate maximum allowances for conductance and for solar heat gain. Formulas relating to solar conductance and solar heat gain are then used to calculate the performance of the proposed glazing layout for comparison with those allowances. The ABCB Glazing Calculator can assist with calculations. Note this is a non-mandatory tool and is neither a compliance tool nor a verification method. Part 13.4 Building Sealing The Part 13.4 Building Sealing DTS provisions addresses chimneys and flus, roof lights, external windows and doors, exhaust fans, constructions of ceilings, walls and floors, evaporative coolers. These provisions are designed to restrict the unintended leakage of outdoor air into the building and loss of conditioned air from the building. Overall, the DTS provisions encourage ventilation that can be controlled by occupants to make use of warmer or cooler outside air when that is desirable and also to maintain a healthy indoor environment. Building Sealing supports that goal by reducing the pathways for unintended leakage of air that has been heated or cooled for the comfort of occupants. This in turn has the capacity to reduce the energy required for artificial heating, cooling and dehumidifying. Part 13.5 Sealing Fans The intention of Part 13.5 is to provide requirements for the installation of ceiling fans for cooling and climates where it is suitable. This part applies to climate zones 1, 2 and 3 and Climate Zone 5 in New South Wales and Queensland. Part 13.6 Hole of Home Energy Usage The intention of Part 13.6 is to provide a collective budget for energy use in a building. The Hole of Home Energy Budget covers a number of factors. Floor area of the home, main heating cooling equipment, main water heater, swimming pool, spa and on-site PV. The Hole of Home Budget can enable trading between the efficiencies of the above types of energy usage within the building including by increased the size of on-site renewables such as solar. The ABCB has produced a Hole of Home calculator that automates the calculations and it is available from the ABCB website. Part 13.7 Services The intention of Part 13.7 Services provisions is to minimise energy loss through the operation of air conditioning, central heating, lighting, heated water supply, pool and spa heating and pumping. The requirements range from the installation of services, limiting the use of electric resistance spa heating, limiting the watts per square metre allowed for lighting, placing restrictions on certain energy sources for both heated water heating and swimming pool and spa heating. Artificial lighting must not exceed specified power allowances five watts per square metre for a Class 1 building, in 13.7.6 artificial lighting. Power allowance can be increased if there are smart lighting controls e.g. movement sensor activated lighting. The lamp power density or illumination power density allowances are as follows. 5 watts per square metre in a Class 1 building, 4 watts per square metre on a veranda, balcony or the like attached to a Class 1 building, 3 watts per square metre in a Class 10A building associated with a Class 1 building. Halogens must be separately switched from fluorescence. Outside lighting must be controlled by a motion sensor or be of high efficiency. High efficiency requires highlight output for each unit of electricity consumed. Requirements for heated water supply systems, including their energy efficiency are located in NCC volume 3 Part B2. These requirements cover the energy source of a system and they must be either solar, heat pump, gas. Only in certain circumstances electric, resistance or wood fire. These provisions have been drafted to favour solar, heat pump and gas hot water supply systems over electric resistance water heaters based on their lower greenhouse gas emissions. Interpreting the housing provisions Question 1. Consider a sealing area in a kitchen family room of a single story home that would usually require a minimum R value of 3 to meet the requirements of the NCC. If 2.4% of that sealing area is uninsulated because of recessed downlights, how much does the R value of the sealing insulation need to increase in order to compensate for this loss? Table 13.2.3W Adjusted minimum R value of insulation required to compensate for loss of sealing insulation area. Minimum R value required to compensate for loss is 4.2W which is an increase of 1.2W. The DTS provisions in clause 13.2.3W contain minimum insulation requirements for roofs, ceilings, floors and external walls and the installation of roof lights. The DTS provisions also include requirements to compensate for gaps in insulation due to service penetrations e.g. downlights and exhaust fans as per this question. Question 2 According to clause 13.3.4 shading how are the distances P, G and H calculated when designing shading for glazing using the housing provisions? Figure 13.3.2B method of measuring P and H. P is the distance between the line of the glazing and the furthest vertical edge of the shading projection or device. G is the distance between the top of the glazing and the lower horizontal edge of the shading project or device. H is the distance between the bottom of the glazing and the lower horizontal edge of the shading project or device. Question 3 What DTS requirements apply to the sealing of external doors and windows? 13.4.4 External windows and doors 1. An external door internal door between a class 1 building and an unconditioned class 10a building. Openable window or similar must be sealed when serving. A. A condition space or B. A habitable room in climate zones 4, 5, 6, 7 and 8. 2. A seal to restrict air infiltration. A. For the bottom edge of a door must be a draft protection device and B. For the other edges of a door or the edges of an openable window or other such opening, maybe a foam or rubber, compressible strip, fibrous seal or the like. 3. A window complying with the maximum air infiltration rates specified in AS 2047 need not comply with 2B. Question 4 For a house located in climate zone 3, what is the minimum number of fans including their diameter? Required for a bedroom 16m2 in size. Table 13.5.2 Minimum ceiling fan requirements in climate zones 1, 2, 3 and 5. The bedroom requires one ceiling fan with a diameter of at least 1200mm. Question 5. What would the swimming pool pump factor be? For a 4.5 star pool pump in Western Australia. Table 13.6.2C Swimming pool pump factor Fp Kilowatt 1000 litres annum. For a 4.5 star pump in Western Australia, the swimming pool pump factor Fp is 0.027 Question 6. What reference documents are referred to in part 13.7 For thermal installation of central heating water piping and heating and cooling ductwork, ASNZS 4859.1 thermal installation materials for buildings, general criteria and technical provisions. For ceiling heating and cooling ductwork, AS 4254.1 ductwork for air handling systems in buildings, flexible duct, AS 4254.2 ductwork for air handling systems in buildings, rigid duct. Also references part B2 of NCC Volume 3 for design and installation of a heated water supply system including the water heater. Energy Efficiency Assessment Methods Whether you choose to use a DTS solution or a performance solution or a combination of them, you may need to provide some evidence that the proposed solution complies with the performance requirements. The NCC recognises four valid ways of assessing possible compliance solutions which are shown on the slide. All methods can be used to demonstrate compliance with the performance requirements when you are using a performance solution. Evidence of suitability and expert judgment can be used when you are using a DTS solution. Alternative non-NCC verification method such as leads ASHRAE or the passive HUS standard may be able to be used if they are accepted by the appropriate authority. Which of the following is a conditioned space for the purposes of NCC Volume 2? Home Office Above Garage with Split System Air Conditioning Condition Space A home office is a habitable room since it may be used for significant periods of the day. It would normally need some form of air conditioning. Bathroom with Underfloor Heating System Non-Conditioned Space As a bathroom is not a habitable room according to the NCC definition. Most underfloor bathroom heating systems have very low wattage and the space in a bathroom tends to be small so the heating load should not be large. This means it should be below the heater capacity of 1.2 kilowatt in the conditioned space defined term. Some room created by enclosing a porch with glazing. Non-conditioned space if it has no mechanical heating or only a small heater. Conditioned space if a heater or sufficient power has been installed in the space. True or False To meet the NCC Energy Efficiency Performance Requirements all newly built Class 1 buildings in Australia must use the same amount of energy for heating cooling and other energy requirements. If you chose False, yes that's right. All newly built Class 1 buildings must achieve a similar standard of energy efficiency but the allowed energy use differs in different climate zones and because of other factors. Besides the climate zone the house is in, the other factors that can affect the actual heating cooling and operational energy loads for different buildings include the size of the building. A bigger building naturally uses more energy than a smaller one and a house with more people living in it will also tend to have greater demands for energy. Therefore, you would not expect a one bedroom unit to use the same amount of energy as a four bedroom family home. On-site energy generation if a building generates some of its own power this can offset the heating and cooling loads and improve its overall energy efficiency. What elements do the energy efficiency provisions in the housing provision cover? Answers 1. Domestic Services H6P2 Energy Usage ABCB Housing Provisions Standard 13.7 Services 2. Air Movement H6P1 Thermal Performance ABCB Housing Provisions Standard 13.5 Air Movement 3. External Glazing H6P1 Thermal Performance ABCB Housing Provisions Standard 13.3 External Glazing 4. Building Ceiling H6P1 Thermal Performance ABCB Housing Provisions Standard 13.4 Building Ceiling 5. Building Fabric H6P1 Thermal Performance ABCB Housing Provisions Standard 13.2 Building Fabric 6. Domestic Services H6P2 Energy Usage ABCB Housing Provisions Standard 13.6 Whole-of-Home Energy Usage True or False Every new Class 1 building in Australia must have a Nata's Energy Rating to Demo. A designer or builder can Demo against each of the Elemental DTS Provisions instead of doing a Nata's Energy Rating in New South Wales. Basics Ratings are used instead of Nata's Energy Ratings. A Different Compliance Option such as a Reference Building or Different Rating System could be used to Demo. Other Useful Resources These resources are not mandatory. They provide guidance and help but nothing in them needs to be complied with in order to comply with the NCC. Nor do the Calculators Act as Verification Methods. This means that you can't present evidence from the Lighting Calculator, for example, to Demonstrate Compliance with the Lighting Require. These resources are not mandatory. They provide guidance and help but nothing in them needs to be complied with to Demonstrate Compliance with the Lighting Requirements in H6P2 Energy Usage. Summary Performance Requirements Part 6 Energy Efficiency in NCC Volume 2 H6P1 Thermal Performance H6P2 Energy Usage DTS Provisions Part H6 Energy Efficiency in NCC Volume 2 H6D1 DTS Provisions H6D2 Application Part H6 Section 13 Energy Efficiency in the Housing Provisions i.e. Elemental DTS Provisions Common DTS Solution 1. House Energy Efficiency Rating plus some Elemental DTS Provisions or 2. All Elemental DTS Provisions Key Points Overall aim is to reduce greenhouse gas emissions from domestic buildings in Australia. Compliance with requirements reduces energy use to maintain a comfortable temperature and operate the building. Heating and cooling loads are key and evidence of compliance is commonly provided through energy rating either NATAS or BASICS in New South Wales. Other elements must be met using DTS Provisions or a compliant performance solution. Thank you for your time. That brings our presentation on using efficiency provisions in NCC Volume 2 to a close. If you'd like more information please visit abcb.gov.au