Inside a NatHERS Assessment, Part 2: Importing and Scaling the Plans

Inside a NatHERS Assessment · Part 2 of 7

In Part 1 we set up the project and climate zone. Now the assessor brings your drawings into the software and makes them dimensionally accurate, because every wall, window and room is traced from these plans.

Loading the drawings as backgrounds

The assessor imports each relevant plan – the site plan, the lower and upper floor plans, and the reflected ceiling plans – as background images to trace over. Reflected ceiling plans that share a drawing sheet are imported twice so each level has its own background. A snap-to-plan function lets the assessor trace precisely along the drawn lines.

Scaling and aligning

Imported plans are just pictures until they are scaled. Using a known dimension, the assessor scales every background so on-screen measurements match the real building. Backgrounds are not automatically aligned to each other, so the assessor aligns them using reference points, ensuring the upper floor sits correctly over the lower floor.

Setting up levels

For a two-storey home, the assessor creates levels – for example Lower and Upper – and keeps them in the correct order. Level order is not cosmetic; reordering levels would change the modelling results, so it is set carefully and left alone.

Why accuracy here is everything

This is the foundation of the model. If the plans are not scaled and aligned correctly, every area, wall length and window size traced afterwards inherits the error. Accurate, well-dimensioned drawings make for an accurate assessment, which is one more reason a complete plan set speeds up your certificate.

References and resources

This series follows the worked example known as NatHERS Example 3. The official documents below are the authoritative sources. We host backup copies for convenience, but the versions on nathers.gov.au are definitive.

• Modelling guidance (the steps this series follows): nathers.gov.au | local copy
• Example 3 architectural drawings (the plans referred to throughout): nathers.gov.au | local copy
• Example NatHERS certificate samples (what the assessment produces): nathers.gov.au | local copy
• A guide to the NatHERS Certificate: nathers.gov.au | local copy
• NatHERS Assessor Handbook (the full handbook, all chapters): nathers.gov.au | local copy
• NatHERS guidance note: nathers.gov.au | local copy

Always use the latest version. NatHERS documents are updated from time to time. We do not guarantee that the versions referenced or backed up here are the most current. Always confirm the latest release on the NatHERS website before relying on them.

Disclaimer. This series is for education only. Its purpose is to simplify and explain the official notes where they may not be clear. It is not a substitute for the original documents or for accredited assessor training. If anything is unclear or you have a question, refer to the original document and contact your college or registered training organisation (RTO), or the NatHERS team.

Next – Part 3: Constructions and Zoning the Home →