The Zimmermann Oz (TZO) is a Passive House builder delivering architecturally refined, energy-
efficient homes across Melbourne and Brisbane. Every home is designed in-house and built to
Passive House principles, delivering thermal stability, fresh air, and long-term performance as
standard.
Led by Jan Knecht, a German-trained builder with over 25 years of experience, our team brings
Passive House expertise to every detail. Each home is carefully considered, technically resolved, and
constructed with precision.
Whether it’s a custom new build, an EnerPHit-standard renovation, or a home from our architecturally
detailed TZO Homes portfolio, we deliver spaces that perform quietly and consistently, year after
year. We design in-house, coordinate consultants, manage construction, and provide detailed
estimates upfront — ensuring transparency, accuracy, and confidence through every stage of
delivery.
The TZO Difference
• German-trained Passive House expertise
• Certified Passive House delivery — with third-party verification and performance modelling
• Full-service design and build delivery
• TZO Homes: architecturally detailed, performance-ready homes
• Transparent quoting and cost clarity
• Certified carbon neutral builds (whole-of-life emissions)
• 20-year structural warranty with subscription-based aftercare
Every home is shaped by performance modelling, built with care on-site, and supported long after
handover, with systems that promote healthier indoor air, stable temperatures, and long-term
efficiency.
We also offer TZO Windows & Doors — a dedicated range of Passive House-level window and door
systems. Engineered to European standards and designed for Australian conditions, the range
includes uPVC, timber, alu-clad uPVC and alu-clad timber options.
Learn more at www.tzowindowsandoors.com.au.
German Master Carpenter, Master Builder Victoria , Master Builder Queensland, Passive Haus Trades Person, Certified Hempblock Installer, High Performance Windows & Door Manufacturer,
This exquisite double brick residence in the heart of Port Melbourne has undergone renovation and extension following passive house principles. The design for the extension was crafted by Heather Cunsolo. In collaboration with Heather, we meticulously applied passive house standards, achieving an impressive 0.52 ACH for this EnerPHit project. All windows and doors were provided by TZO Windows and Doors.
To date, we have maintained regular contact with the client to monitor the performance of the house and their experience with living in it. The results are impressive, with energy bills as low as $2 per month.
The Glow House Project, designed by Gruen Eco and PHPP by Elsie Wang, is a Certified Passive House. This project marked our first collaboration with Burkhard Hansen and Carbon Lite. With prefabrication and coordination from TZO windows and doors, we achieved lockup within three weeks.
We thank our clients, Ying and Michael, who contributed ideas like adjusting the wall mixer to avoid triggering the heat pump at neutral position. This illustrates the importance of teamwork among designers, builders, and clients. The project was completed successfully.