🌡️ What is a U-Value?
Windows are usually the weakest point in a building's "envelope," they have a massive impact on your star rating.
Is your insulation budget hitting a brick wall? 🧱💸
Going from no insulation to R2.0 is a game-changer. But jumping from R5.0 to R7.0? You might be spending thousands for just a tiny 1–2% improvement in thermal performance. 📉
In a 7-star NatHERS world, it’s not about the thickest batt—it’s about the smartest build. If your windows are leaking heat or your downlights aren't sealed, high R-values won't save you.
Why More Isn't Always Better: The Law of Diminishing Returns in Insulation
How much does a BASIX Certificate cost in 2026?
How much does a BASIX Certificate cost in 2025?"
Here is a break down of the government and consultant fees.
Spot the differences.
Part of the job of a Thermal Performance Assessor is playing ’Spot the difference’ with a design.
The specification needs to fit!
Recently I came across a NatHERS rating provided to a builder who was asking for some explanation.
The walls in his construction were on plan as 90mm.
His assessor had noted that he required R3.5 polystyrene insulation!
This product is 180mm thick!
Construction knowledge goes a long way to providing results that work in the real world. Experience helps provide assessments that a builder can actually build.
For the record, R2.7 is the maximum in a glass fibre batt that will fit in a 90mm wall. Thicker solutions and higher R-values can be specified, but this needs to be communicated with the architect and designed to suit.