Granny Flat Design

Modern Granny Flat Design Across Sydney & Western Sydney

Granny flats have become one of the most popular additions to residential properties across Fairfield, Campbelltown , Parramatta, Liverpool, Bankstown, Blacktown, Penrith, Sydney, Inner West

Whether you’re building for extended family, rental income, or future resale value, Trinity Design & Planning delivers high-quality, approval-ready granny flat designs tailored to your property and lifestyle.

A modern small house with white siding, black trim, a black metal roof, and a lush green lawn.

Why Build a Granny Flat?

  • Affordable way to add living space

  • High rental demand across Western Sydney

  • Ideal for multi-generational living

  • Often eligible for CDC (faster approvals)

  • Increases overall property value

  • Efficient, low-maintenance design options

Our Granny Flat Design Services Include:

Site Feasibility Assessment

Before we begin designing, we confirm that your site meets key granny flat requirements, including:

  • 450m² minimum lot size (CDC dependent)

  • 12m mininum frontage

  • Sewer mains clearance

  • Private open space ratios

  • Setback controls

  • Existing dwelling placement

A detailed site plan or blueprint showing property boundaries, structures, fencing, vegetation, and various measurements and annotations for construction or landscaping.

Custom Floor Plans Tailored to Your Needs

We design spaces that feel practical, modern and functional, typically including:

  • 1–3 bedrooms

  • Open-plan kitchen/living

  • Built-in laundry

  • Outdoor patio or deck

  • Accessible layouts if required

Every plan is designed to maximise natural light,
maintain privacy from the main dwelling, and comply with NSW planning rules.

Floor plan of a residential unit showing rooms labeled Living Area, Kitchen, Meals, Bedroom 1, Bedroom 2, Bath, Laundry, and WC with wall measurements.

Architectural Drawings for DA or CDC

Your final set of drawings includes:

  • Site plan

  • Floor plans

  • Elevations

  • Sections

  • Roof plan

  • Window & door schedule

We also assist with:

  • BASIX Certificate

  • Stormwater concept plans

  • Statement of Environmental Effects (if DA required)

  • Section 10.7 (2 & 5)

  • other relevant documentation

CDC vs DA — Which Is Better for You?

Many granny flats across suburbs like Fairfield, Liverpool, Blacktown, Campbelltown, Penrith etc. qualify for CDC (Complying Development Certificate), meaning faster approvals and fewer delays.

If your block doesn’t meet CDC requirements, we can prepare a DA (Development Application) package through your local council.

Designed for Buildability & Affordability

We work with the design-build process in mind, ensuring your builder has clear, accurate drawings that reduce variations and cost blowouts.

Builders appreciate our:

  • Millimetre-accurate dimensions

  • Clear construction notes

  • Logical drafting layout

  • Compliance-first approach

Start Your Granny Flat Project Today

For investment, family support or extra space, we guide you from concept to approval.

Contact us today via email or call 0401 779 749


Book Your Granny Flat Consultation