Many Perth families love where they live, but simply need more space. When moving isn’t the preferred option, the key question becomes: should you extend out, or build up?
Choosing between a ground floor extension vs a second storey addition is one of the most important design decisions you’ll make. Each option offers distinct lifestyle benefits, and understanding how they relate to your block, suburb and long-term plans will help you create a home that feels beautifully resolved.
With more than three decades of experience across Perth’s character, coastal and family suburbs, Addstyle shares what to consider when deciding the best path forward.
Ground-Floor Extensions
A ground floor extension expands your home outward, perfect for families with larger blocks. It offers open-plan living with seamless indoor-outdoor flow and easy single-level access, ideal for suburbs like Floreat, Duncraig, and City Beach.
Advantages
- Easy, single-level living: No stairs, perfect for young families or downsizers.
- Indoor–outdoor living: Creates natural flow to alfresco areas, gardens, or pools.
- Simpler structure: Usually requires less complex engineering than a second-storey.
What to Consider
- Backyard space is essential: Extending outwards requires enough land to maintain balance and proportion.
- Planning requirements: Boundary setbacks and site coverage must comply with local council guidelines.
Cost Overview
Ground-floor extensions are generally less expensive than adding another level due to less scaffolding requirements and staircase costs. However, final costs depend on site conditions, access, and the chosen finishes. In Perth, expect costs to vary based on location and block complexity.
Learn more: What to Expect When Renovating Your Perth Home.
Second-Storey Additions
A second storey addition adds a full new level, perfect for smaller lots or inner-city homes with limited yard space. In suburbs like Subiaco, Mount Hawthorn, or North Perth, building up maximises space and separates living areas from bedrooms.
Advantages
- Keep your backyard: Gain extra living space without sacrificing your outdoor area.
- Adds potential views: A well-designed upper level can capture city, parkland, or ocean views.
- Creates privacy zones: Perfect for parents’ retreats or children’s bedrooms upstairs.
What to consider
- Cost: Second storey projects generally cost more per square metre due to extensive scaffolding requirements and the requirement of a staircase.
- Accessibility: Stairs may not suit every household, particularly for older residents.
Cost Overview
While second storey additions can cost more, it is entirely dependent on the details. For a quality, architecturally considered second storey addition in Perth, you can expect to invest:
💰 $350,000 to over $700,000+
The range is intentionally broad because every home, design challenge, and structural requirement is unique. What matters most is having clear, upfront advice, something we prioritise from your very first consultation.
Learn more: Blending Your Second-Storey Addition with the Existing Structure.
Lifestyle and Design Considerations
When choosing between a ground floor extension or second storey addition, think about what suits your lifestyle. Recent analysis shows that renovations now make up about 40% of residential construction spending, showing more homeowners are improving rather than moving.
Young families and downsizers prefer single-level layouts, while those with teenagers or views to capitalise on, opt to add an upper floor.
Your suburb, block size, and home style will also shape your choice. Smaller inner-city lots often build up, while larger suburban blocks have room to extend out. Character homes may face heritage or height restrictions, but with the right design, either option can improve your lifestyle and add lasting value to your Perth home.
Dive into the latest trends: Home Renovation Trends for 2025: Colours, Materials & Styles.
Council Approval and Regulations in WA
In Perth, both types of extensions require local council approval and compliance with the Residential Design Codes (R-Codes).
- Ground floor extensions: Typically assessed for boundary setbacks and site coverage.
- Second storey additions: Reviewed for height limits, overshadowing, and privacy.
Navigating approvals can be complex, but Addstyle manages it all for you, ensuring compliance while preserving your home’s integrity.
Project Highlights:
Ground Floor Extension – Claremont Family Home
Addstyle transformed a 1950s Claremont bungalow into a refined family home that blends heritage character with modern luxury.
The Challenge
The original home felt cramped and disconnected, with limited light and functionality. The owners wanted to preserve its charm while creating open, practical spaces for family living.
The Solution
We restored the original façade and added a modern rear extension with a new kitchen, living areas, and a seamless alfresco connection.
The result is a light-filled, elegant home that blends classic charm with contemporary comfort for modern family living.
Second Storey Extension – Mount Hawthorn Home
Addstyle transformed a classic Mount Hawthorn home into an elegant family retreat that perfectly balances heritage charm and modern design.
The Challenge
The original home lacked space and functionality. The family needed room to grow while keeping the character façade and outdoor areas intact.
The Solution
We added a refined second-storey with a main suite, ensuite, walk-in robe, and home office. The reconfigured ground floor introduced open-plan living, a sleek kitchen, and a seamless alfresco connection.
The renovation brought light, space, and efficiency, earning the 2025 HIA Perth Housing Award and creating a home of lasting luxury and comfort.
How Addstyle Helps You Choose the Right Extension
No two families or homes are the same. That’s why our approach begins with understanding your needs and long-term goals before recommending whether to extend out or up.
With over 37 years of experience and more than 220 peer-judged industry awards, we are Perth’s most awarded renovation specialists. Our expert designers, builders, and consultants guide you through each step from concept to completion, ensuring a seamless, stress-free experience.
Use our Budget Indicator for a quick estimate and visit our Claremont Design Studio to plan your dream renovation.
The Smartest Way to Create More Space
There’s no one-size-fits-all answer to the ground floor extension vs second storey addition question. Your decision depends on your land size, lifestyle, budget, and long-term vision.
Addstyle Master Builders can help you make the right choice for your home.
Contact us today at (08) 9345 2333 or online for a complimentary consultation and discover the best way to enhance your lifestyle.
