Commercial Achitecture by Leithal Designs
Where Luxury, Strategy, and Build-Ready Precision Converge
Luxury commercial architecture is not created through chance. It is achieved through a disciplined design methodology that blends creativity with compliance, aesthetics with operational logic, and ambition with construction intelligence. At Leithal Designs, our architectural approach brings clarity, certainty, and elevated design to every commercial project—shaping spaces that perform as beautifully as they look.
From multi-level workplace environments to premium retail fitouts, hospitality venues, medical spaces, and government facilities, we specialise in crafting high-end commercial spaces that align with long-term business goals, user needs, and the realities of construction.
With more than two decades of experience in complex commercial environments (and a values-based process designed to mitigate risk) our firm is known for delivering luxury outcomes through rigour, technical depth, and an unwavering commitment to detail.
A Story Grounded in Commercial Expertise
Leithal Designs was founded by Sonia Leith, a deeply experienced commercial designer and QBCC-licensed Commercial Building Designer, with a background spanning high-level architectural projects across Australia and New Zealand.
Before establishing the studio, Sonia spent years working within multidisciplinary commercial environments, contributing to:
- Complex hospital upgrades
- Multi-storey commercial buildings
- Government service centres
- Premium workplace refurbishments
- Retail precinct developments
- Commercial hospitality venues
- Large-scale private sector fitouts















Our Mission
Our mission is to lead South-East Queensland in luxury commercial architecture by combining design excellence with strategic, technically sound project delivery.
We achieve this through:
- A construction-aware design process that reduces risk
- High-precision architectural documentation
- Premium, sustainable material selection
- Deep understanding of commercial code, compliance, and functionality
- Local knowledge of SEQ’s unique planning, climate, and construction conditions
- Architectural design that elevates brand presence and business performance
We do not design for today—we design for the long life of your commercial space.
Our Values
To Create Intelligent, Beautiful, and Build-Ready Commercial Environments
1. High Standards as a Non-Negotiable Foundation
Luxury commercial environments must withstand significant use while still presenting at a premium level. Our obsession with detail—materiality, joinery lines, functional flow, acoustics, circulation, and lighting—elevates ordinary workplaces and retail spaces into refined, enduring environments.
2. Experience That Reduces Risk
With two decades of commercial architectural experience, our founder’s knowledge of building codes, sequencing, consultants, and approvals is a key reason our projects run smoothly. Our process is designed to eliminate assumptions early, protecting investments from the most common sources of cost escalation.
3. SEQ-Specific Knowledge
Brisbane and the Gold Coast demand climate-appropriate design, local compliance insight, and trusted relationships with builders and consultants. This regional expertise may significantly reduce risk and streamline the approval and construction process.
4. Sustainability as a Marker of Modern Luxury
Today’s luxury commercial clients value smart, sustainable environments that support wellness, efficiency, and long-term durability. Our approach includes:
- Low-energy design principles
- Climate-responsive materials
- Biophilic integration
- Wellness-enhancing spatial strategies
- High-performance acoustic and lighting solutions
5. Transparency and Collaboration
Our values-based approach ensures clear communication, structured decision-making, and alignment across stakeholders—including builders, consultants, and certifiers.
Our Commercial Architecture Methodology
A Six-Phase Process Designed to Protect Your Investment
Luxury outcomes require predictable processes. Our architectural framework—from feasibility to construction advisory—is structured to eliminate guesswork and ensure the design intent carries through to completion.
1. Feasibility & Research
We assess site conditions, regulatory constraints, operational needs, and budget expectations to determine the viability of your vision.
2. Conceptual Architecture & Spatial Planning
We craft spatial strategies, circulation flows, zoning, and early design language that align with business goals and brand identity.
3. Detailed Architectural Documentation
4. Planning Approvals & Development Applications
We prepare and coordinate material required for DAs, working with certifiers and consultants to align submissions with local requirements.
5. Construction Certificate (CC) Support
6. Tender & Builder Coordination
What Makes Our Commercial Architecture Different?
Architectural + Interior Integration
Founder-Led Technical Oversight
Premium & Long-Lasting Materiality
Trusted by Queensland’s Leading Organisations
Our portfolio includes:
- Infinity Group Australia
- Harcourts
- Hearing Australia
- Target Physio
- Australian Choice Exports
- Federal & State Government Departments
Their testimonials highlight our communication, attention to detail, and professionalism—key markers of trust in commercial architecture.
Impact & Results
Our architectural work supports environments where:
- Staff wellbeing and productivity increase
- Customers engage more deeply with the brand
- Processes become more efficient through intelligent spatial design
- Acoustics, lighting, and circulation perfectly support commercial operation
- Materials remain resilient and refined, even under heavy use
- Businesses express their identity with clarity and confidence
A Commercial Architecture Partner You Can Trust
Your commercial project is a long-term investment.
Our role is to protect it—through clarity, architectural discipline, and uncompromising attention to detail.
If you’re planning a new commercial build, refurbishment, expansion, or multi-tenancy project in Brisbane or the Gold Coast, our team may guide you through every stage with confidence and care.