Performance
by Design.

Integrated Passive House consulting — uniting modelling, certification and advanced building science to ensure measurable and buildable performance.

About Us

LAB Design Passive House project

LAB Design is a specialist Passive House and building-science consultancy working with architects, builders and suppliers across Australia and internationally.

Since 2014, we have supported more than 200 projects pursuing the Passive House standard, providing independent modelling, certification and technical analysis to deliver verified performance.

We do not produce architectural designs. Our role is to strengthen project teams with rigorous, evidence-based guidance that supports buildable and compliant outcomes.

We prioritise disciplined optimisation, avoiding unnecessary over-engineering while maintaining certified Passive House performance.

Scott and Madonna both teach within the Certified Passive House Trades program, contributing to industry education and raising standards in high-performance construction. In addition to consulting on hundreds of projects, they have designed and constructed two of their own certified Passive Houses — experience that informs their practical and buildable approach to performance.

Scott and Madonna Stewart — founders of LAB Design

Meet Scott & Madonna

Scott Stewart — Certified Passive House Designer and Certifier

Scott Stewart

Certified Passive House Designer & Certifier

Scott is a Certified Passive House Designer and Passive House Institute Certifier — one of only a small number in Australia.

With a background in aeronautical engineering, building design and a 20-year Air Force aviation career, he brings analytical precision and practical problem-solving to complex building-performance challenges. His work focuses on PHPP modelling, thermal bridge analysis and certification strategy.

Madonna Stewart — Certified Passive House Tradesperson and WUFI Professional

Madonna Stewart

Certified Passive House Tradesperson & WUFI Professional

Madonna is a Certified Passive House Tradesperson and WUFI Professional.

Beginning in the family construction industry and followed by 12 years in Air Force aviation, she combines practical construction insight with technical precision. With a science background and international training in WUFI modelling, she specialises in hygrothermal and condensation-risk analysis.

Licences & Memberships

Certifications
  • Passivhaus Institute Building Certifier
  • Certified Passivhaus Designer
  • Certified Passivhaus Tradesperson
  • WUFI® Professional
Qualifications
  • Bachelor of Building Design
  • Bachelor Technology (Aeronautical Engineering)
  • Bachelor Science
  • Diploma of Project Management
Memberships & Registrations
  • Member of APHA & IPHA
  • BDAA: 1633-14
  • QBCC: 15130400
  • VBA: DP-AD 63141
Certified Passive House Designer seal
Certified Passive House Tradesperson seal
Passive House Certifier seal
Services

Integrated consulting across
certification, analysis and project support.

LAB Design provides specialist Passive House and building-science consulting to support architects, builders and product suppliers from concept through to certification.

Passive House Certification

Independent Passive House Institute accredited certification services, providing clarity, oversight and compliance throughout the project lifecycle.

Thermal Bridge Analysis

Quantification and optimisation of junction performance to support passive house compliance, including support for window suppliers requiring Passive House data.

Hygrothermal & Condensation Risk Assessment

Advanced moisture and condensation modelling aligned with NCC requirements, including Condensation Management Performance Solutions where required.

Passive House Project Consulting

Engaged consulting structured across three key phases — Feasibility, Design and Construction. Depending on scope, services may include:

Initial PHPP modelling (mechanical & glazing specifications)

Thermal bridge analysis

WUFI hygrothermal modelling

Construction detail optimisation

Coordination with builders, architects & engineers

Certification coordination with the appointed Certifier

PHPP updates to as-built stage

Passive House Database submission for certification

LAB Design — Kearney Spring Passive House project
Passive House — exterior elevation at dusk
16 Sorrento — 16 Sorrento Passive House by LAB Design
Passive House interior — stairwell and living
Passive House interior — kitchen detail
Passive House interior — hallway

Get in Touch

If you are planning a Passive House project, require certification services, or need specialist building-science support, we welcome the opportunity to discuss your project.

LAB Design — Passive House & Building Science Consulting

Based on the NSW Mid-North Coast

Working Australia-wide and internationally

16 Sorrento — Passive House by LAB Design