CPPHSA4013
Conduct NatHERS assessment of existing residential buildings


Application

This unit of competency specifies the outcomes required to assess the thermal performance of existing residential buildings using software tools that are accredited under the Nationwide House Energy Rating Scheme (NatHERS) for regulatory purposes.

The unit supports the work of NatHERS assessors engaged in assessing, and making recommendations for improving, the thermal performance of existing residential buildings.

In some jurisdictions, this unit of competency may form part of the accreditation, licensing, legislative, regulatory or certification requirements for NatHERS assessors.


Elements and Performance Criteria

Elements describe the essential outcomes.

Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold italicised text is used, further information is detailed in the range of conditions.

1.

Plan the NatHERS assessment.

1.1.

Need for assessing thermal performance of existing residential building is clarified with client.

1.2.

Effective communication strategies are used to assist in establishing rapport with the client and in responding to client questions and concerns.

1.3.

Potential risks are identified and suitably managed.

1.4.

Documentation required for the assessment is obtained.

1.5.

Authority to proceed is obtained from client before commencing, and reconfirmed as appropriate during the assessment.

2.

Gather information on existing residential building.

2.1.

Building drawings and other supporting documentation for use in assessment, including details of proposed building additions and alterations, are identified and accessed from relevant sources in line with organisational procedures and regulatory requirements.

2.2.

Site inspections are planned.

2.3.

Potential hazards associated with conducting a site inspection of an existing building are identified to ensure risks are suitably managed.

2.4.

Information required from client is obtained before conducting site inspection.

2.5

Details of site inspection are agreed with client before conducting inspection.

2.6.

Site inspection is safely conducted and information required for assessment is gathered.

2.7.

Limitations of data collected are identified in line with organisational procedures.

3.

Enter information into thermal performance assessment tool.

3.1.

Computer equipment and software required for the assessment are identified and checked for serviceability.

3.2.

Building information is extracted from building plans and specifications, outcomes of site inspection, other supporting documentation and discussions with client.

3.3.

Building information is correctly entered into thermal performance assessment tool.

3.4.

Methods for entering information relating to non-standard building materials and designs are used correctly.

3.5.

Methods for entering information required for assessing and rating alterations and extensions are implemented correctly.

4.

Apply thermal performance assessment tool.

4.1.

Relevant functions of thermal performance assessment tool are used to generate outputs in relation to thermal performance of the building, including proposed additions and alterations if required.

4.2.

Thermal performance assessment tool outputs are identified and analysed.

4.3.

Errors in data entry and assessment are identified and corrected.

4.4.

Limitations of software are identified and considered during assessment.

5.

Identify options for improving thermal performance.

5.1.

Sources of technical advice on building thermal performance are identified.

5.2.

Assumptions and limitations inherent in thermal performance assessment tool are considered when interpreting outputs.

5.3.

Thermal performance tool outputs are interpreted to identify strengths and weaknesses in thermal performance of building.

5.4.

Options for improving thermal and environmental performance and for meeting regulatory requirementsare identified based on criteria.

5.5.

Interactions of thermal performance improvements on other aspects of building performance are identified and advice is provided to client.

5.6.

Impact of options is evaluated by reassessing the building using the thermal performance assessment tool.

6.

Report outcomes of thermal performance assessment.

6.1.

Results and recommendations, along with supporting evidence, are collated and documented.

6.2.

Results and recommendations of thermal performance assessment are explained to the client.

6.3.

Reports and other documentation associated with thermal performance assessment are lodged with regulatory authorities if required, and securely stored to be readily retrieved.

Evidence of Performance

A person demonstrating competency in this unit must satisfy the requirements of the elements, performance criteria, foundation skills and range of conditions of this unit.

The person must also assess the thermal performance of one existing residential building. The assessment must be undertaken using a Nationwide House Energy Rating Scheme (NatHERS) software tool accredited under NatHERS for regulatory purposes in a mode appropriate to the type of assessment. The residential building must be drawn from the following classes of buildings under the National Construction Code (NCC): Class 1 buildings, sole occupancy units (SOU) in Class 2 buildings, or Class 4 buildings.

In doing the above, the person must:

gather building information from documents and existing building required for thermal performance assessment and correctly enter this information into a NatHERS software tool

gather relevant site information to support NatHERS assessment

identify and analyse the outputs of thermal performance assessment tool

identify limitations to the software and items that cannot be assessed

identify ways to improve the thermal performance of existing residential building.


Evidence of Knowledge

A person demonstrating competency in this unit must demonstrate knowledge of:

Australian climatic zones:

climate data used in thermal performance assessment:

diurnal temperature range

humidity

irradiance

maximum and minimum temperature

solar geometry

wind speed and direction

climatic zones and characteristics

building alterations and additions:

effects on building thermal performance

performance standards

regulations

type and scale of alterations and additions

building thermal performance:

benefits of thermal performance assessment

impact of building design and building materials on building thermal performance

relationship between building thermal performance and thermal comfort

thermal performance principles:

glazing, shading and insulation for controlling temperature

orientation for heating

thermal mass for storing

ventilation for cooling

thermal performance standards:

current performance standards

documentation of assessments and ratings

legal requirements

uses

ways of improving thermal performance of existing residential buildings:

draught proofing

floor coverings

glazing

insulation levels

landscaping and planting

overshadowing

passive heating and cooling

shade

structural changes

ventilation

window coverings

window size, location and type

zoning and layout

thermal performance properties of common building materials

commonwealth, state and territory, and local government legislation and regulations impacting on thermal performance assessment relating to:

building and construction

building thermal performance

consumer protection and trade practices

environment protection

work health and safety

energy and power:

terminology:

energy efficiency

energy loads

heating and cooling loads

latent heat

power

primary energy source

units of measurement

uses, cost and environmental impact of energy in residential buildings

greenhouse gas emissions:

potential ways of reducing operational greenhouse gas emissions through building design

relationship between building design, energy consumption and greenhouse gas emissions

NatHERS software tools:

types of NatHERS software tools

assumptions and limitations inherent in NatHERS software protocol and accredited software

criteria for the selection of particular NatHERS software tools

scope and function of NatHERS software tools

operating procedures for one or more NatHERS software tools

properties of materials, such as heat transfer coefficients and U-value, thermal resistance and R-value, reflectivity, absorptance, solar heat gain coefficient and emissivity

star rating

site inspection procedures

thermal comfort:

definition of thermal comfort

physical factors that influence thermal comfort

requirement for thermal comfort

role of thermal comfort in building thermal performance assessments.


Assessment Conditions

The following must be present and available to learners during assessment activities:

equipment:

NatHERS software tool

computer equipment suitable for using NatHERS software tool

materials:

relevant codes, standards and government regulations

building documentation for residential buildings to be assessed

householder for provision of information relevant to building thermal performance assessment

residential building drawn from the NCC classes of buildings specified in the performance evidence

technical reference library with current publications on:

Australian climatic zones

building design and materials

house energy rating system (HERS)

building thermal performance for existing buildings

manufacturer product information on building products and materials

NatHERS

relationships with team members and supervisor:

assessment activities are performed on an individual basis under general supervision.

Assessor requirements

As a minimum, assessors must satisfy the assessor requirements in the Standards for Registered Training Organisations (RTOs) current at the time of assessment. Assessors must also hold current accreditation with a NatHERS Assessor Accrediting Organisation.


Foundation Skills

This section describes the language, literacy, numeracy and employment skills essential to performance in this unit but not explicit in the performance criteria.

Skill

Performance feature

Learning skills to:

maintain up-to-date knowledge of information required to make recommendations based on the outputs of NatHERS software tools.

Numeracy skills to:

calculate and interpret the outputs of NatHERS software tools data associated with conducting thermal performance assessments, such as U-value, R-value, reflectivity, absorptance and emissivity

interpret and extract data from building plans and specifications.

Oral communication skills to:

ask questions to clarify customer requirements.

Reading skills to:

identify and interpret documents and information on key matters associated with thermal performance assessments, such as climatic zones and the thermal properties of building materials.

Technology skills to:

operate computer equipment and peripherals

enter data and use the functions of NatHERS software tools and other general purpose software packages.

Writing skills to:

complete standard forms

prepare routine reports on the outcomes of NatHERS assessments.

Self-management skills to:

interact with clients from diverse social, economic and cultural backgrounds.


Range Statement

This section specifies work environments and conditions that may affect performance. Essential operating conditions that may be present (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) are included. Bold italicised wording, if used in the performance criteria, is detailed below.

Information must include:

air leakage features:

fans

wall vents

attachments to other buildings externally

building sealing

construction materials

dimensions

electrical fittings:

ceiling fans

exhaust fans

glazing

insulation levels:

ceiling

floors

walls

orientation

overshadowing

shading

thermal mass

ventilation

windows:

size

style

type of frame

type of glass

zoning and layout.

Outputs must include at least two of the following:

cooling loads

data for individual zones

heating loads

information on building properties

latent cooling

rating and non-rating mode

temperature graphs.

Options must include at least two of the following:

air leakage reduction

draught proofing

floor coverings

glazing

insulation levels

internal and external window coverings

landscaping and planting

passive heating and cooling

shade

structural changes

ventilation.

Criteria must include at least one of the following:

cost

outputs of thermal performance assessment

practicality

thermal performance properties of building elements

type of building.


Sectors

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