Energy ratings that reflect how your home is actually built
7-star NatHERS and Whole of Home ratings, town-planning ESD and blower door testing for builders, designers and owners across Victoria. Few energy raters also test airtightness — we do both, so your rating can use the real result.
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Services across Victoria
From the first sketch to handover: thermal ratings, planning reports, commercial compliance and on-site testing — one team, one point of contact.
7-Star NatHERS & Whole of Home
Accredited ratings for new homes and major alterations, with design advice to hit 7 stars without over-spending.
NatHERS packages → NatHERS · EnergyExisting home NatHERS
Star ratings for homes that already stand — before you renovate, buy, sell or upgrade.
Learn more → Town planningBESS / Sustainable Design Assessment
BESS scorecards and SDA reports for council planning applications. (Sustainable design — not NDIS SDA.)
Learn more → Town planningWSUD
Water Sensitive Urban Design assessments and reports for planning permits.
Learn more → CommercialSection J / JV3
NCC Section J energy efficiency for commercial and Class 2–9 buildings — DTS or JV3 modelling.
Learn more → Smaller extensionsDTS Part 13 / glazing
Deemed-to-Satisfy energy efficiency and glazing calculations — often the simpler path for small additions.
Learn more → CompliancePerformance Solutions
Energy efficiency Performance Solutions when a design can’t, or shouldn’t, follow the DTS path.
Learn more → Town planningWaste & Construction Management Plans
Council-ready Waste Management Plans and Construction Management Plans for planning applications and permit conditions.
Learn more → TestingBlower door testing
Measured airtightness (ACH50) on site — and the option to use it in your NatHERS rating.
Learn more →Your rating can use your home’s real airtightness
A standard NatHERS rating assumes a default air-leakage figure of 10 air changes per hour (ACH). We model in HERO and, after a blower door test, can use your measured ACH instead — so a well-built home gets credit for it.
Illustrative example only. Every home is different and the result depends on the design and the test.
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Hand over a home you know is airtight
Builders are responsible for delivering an airtight home at handover. Get it independently verified, find and fix any issues before the keys change hands, and keep the report on file.
Builder & designer packages →Know it was built right
Your home is your biggest investment. An independent rating and airtightness test tells you how it really performs — and what to ask your builder about before handover.
Talk to us →From drawings to certificate
Send your drawings
Working drawings, address and what you need. We confirm the right pathway — NatHERS, DTS, Section J or planning reports.
Clear quote
Scope, inclusions and revisions spelled out. Repeat and multi-dwelling work quoted to suit.
Assess & advise
Standard turnaround is 2–5 business days from working drawings, with 24–48 hour priority available.
Certificate & report
Documents ready for your building surveyor or council, with plain-English notes on what drives the result.
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A Victorian family business since 2009
Geokal Services is a family business led by Director George Kalajdzic. We’re based in the Melton area and work right across Victoria — from single extensions to multi-dwelling developments and commercial projects.
- Accredited NatHERS assessor (Thermal Performance and Whole of Home) — DMN/11/2035
- Existing Home Energy Assessor — NEH-2025-00026
- ATTMA accredited tester #13381 for airtightness testing
- Ratings modelled in HERO, with measured ACH where tested
Send your drawings for a quote
Serving all of Victoria. Email your working drawings and site suburb — we’ll come back with a clear scope and turnaround.