How to Turn an Old Garage Into a Beautiful Studio or Guest Suite

A practical guide to transforming under-used space into something valuable, functional, and beautiful.

Converting a garage is one of the smartest ways to add living space to your home without a major extension. With the right design, approvals, and planning, an old garage can become a bright, modern studio, teenage retreat, home office, or guest suite. Here’s how the process works and what to expect.

1. Start With the Potential: What Could Your Garage Become?

Garages often have great bones—solid walls, existing slab, and good access. This makes them ideal for conversion.

Popular ideas include:

Self-contained guest suite
Airbnb-style accommodation
Teenage retreat
Home office or creative studio
Gym or wellness room
Granny flat–style space (depending on approvals)

Imagine the value you can add by turning unused storage into a functional extension of your home.

2. What Needs Upgrading?

Even if your garage looks solid, it will almost always need:

Proper insulation
New windows and doors
Waterproofing
Electrical and lighting upgrades
Plumbing (if adding a bathroom or kitchenette)
Flooring over the slab
Heating and cooling

These upgrades bring the space up to home-grade quality.

3. Approval Pathways: DA vs CDC

A garage conversion can go through either Complying Development (CDC) or a Development Application (DA)—depending on your site.

CDC (Complying Development Certificate)

Faster approval through a private certifier.

Works if your garage is:

Already part of the main house
Not heritage-listed
Positioned within required setbacks
Meeting all height and boundary rules

DA (Development Application)

Approval through your local council.

Needed if:

Your site has constraints (heritage, flood, bushfire)
You’re adding a bathroom or changing the building footprint
You want a more custom design
The garage is too close to boundaries

At Residential Studio, we assess your site and let you know the best pathway before we begin.

4. Timeline: How Long Does It Take?

Here’s a simple guide:

Design + drawings: 2–6 weeks

Approvals (CDC or DA):

CDC: 2–4 weeks
DA: 6–12 weeks

Construction: 6–12 weeks depending on scope

Total: 10–20 weeks from concept to finished space.

5. Before and After: What This Transformation Typically Looks Like

Before

Concrete slab
Roller door
Poor insulation
Dark, cold space
Used for storage or collecting clutter

After

New façade with sliding doors or a feature window
Fresh flooring and insulation
A bright, modern interior
Bathroom or kitchenette (if desired)
Warm lighting and stylish finishes
A space that feels like part of the home, not an add-on

This type of conversion can dramatically improve how your home functions—and often increases property value.

6. Budget Guide

Costs can vary depending on size and whether you add plumbing, but most conversions fall into these ranges:

Basic studio conversion: $25,000–$45,000
Studio with bathroom: $45,000–$90,000
High-end guest suite: $90,000+

We provide clear cost guidance early in the design process so there are no surprises.

7. How Residential Studio Helps

We guide you from start to finish:

Site visit and design advice
Concept drawings
Advice on DA or CDC
Full documentation for approvals
Coordination with certifier, engineer, and builder
Support through construction

Our goal is to make the process smooth, stress-free, and perfectly aligned with how you want to live.

Ready to transform your garage?

If you’re thinking about creating a studio or guest suite, we’d love to help bring your vision to life.

Get in touch with Residential Studio to book your Project Discovery Call.

Retrofit An Old Garage