Green Building
A heat pump or a solar array performs only as well as the building around it. Insulation, glazing and airtightness decide how much heating and cooling load you actually have — and home energy ratings are how you measure it.
Ceiling, wall and underfloor insulation is usually the highest-return, lowest-glamour upgrade available — it reduces the load every heating/cooling system has to work against.
Single-glazed windows are often the single biggest source of heat loss (winter) and heat gain (summer) in an older home. Double glazing, low-E coatings and window coverings all move the number.
Australia uses NatHERS (0–10 stars); the USA uses the HERS Index (lower is better) and ENERGY STAR certification. Both estimate how much energy a home needs before any appliance choice is even made.
Guides & articles
- 8 min readWhat your NatHERS or HERS rating assumes about how you'll live in the houseNatHERS and HERS ratings model a standardised occupant, not your family. Here's what that assumption actually covers and why it matters.
- Australia8 min readWhy the same house can get two different NatHERS star ratingsTwo NatHERS assessors, same house, different star ratings. It happens more than people admit — here's why, and what actually drives the gap.
- 7 min readWhy NatHERS and HERS ratings ignore your actual orientationA NatHERS or HERS rating models your house on paper, but the assessor's orientation assumptions can miss what actually happens outside your windows.
- 7 min readCan you get a 7-star NatHERS rating and still freeze in July?A high NatHERS or HERS score doesn't guarantee comfort. Here's what the rating actually measures, and where the gap between star rating and lived experience opens up.
- 8 min readWhy a NatHERS or HERS rating won't tell you what to fix firstA star rating tells you where a house lands, not why. Here's how to read the assessor's supporting data to find your actual weak point.
- Australia6 min readWhy your NatHERS star rating can change without touching the houseA NatHERS star rating isn't fixed to the house — orientation data, software versions and even climate files can shift the number. Here's what actually moves it.
- 6 min readDouble vs Triple Glazing: When the Extra Pane Is Actually Worth ItTriple glazing earns its keep in genuinely cold climates and noisy sites. In a mild Australian or southern-US climate, the payback math rarely favours the third pane over spending the same money elsewhere.
- 6 min readAir Sealing Before Insulation: The Order of Operations That Actually Saves EnergyInsulation slows heat transfer through a surface. Air leaks bypass that surface entirely. Seal the gaps first, or you're insulating a house that's still breathing uncontrolled air through its own envelope.
- 6 min readWhat a NatHERS or HERS Assessor Actually Checks On-SiteThe star rating or index number on your certificate is the output of a detailed on-site inspection, not a desktop guess. Knowing what an assessor actually measures explains why two similar-looking homes can score very differently.
