How to Choose the Right Block for Duplex Development in Perth

Building a duplex in Perth is a smart way to add value, create extra living space, or earn rental income. But before you start, you must choose the right block of land. The block you pick can affect your design, cost, approvals, and long-term resale value. In Perth, many suburbs now support duplex projects, and buyers are looking for homes that offer space, comfort and great layouts. In this guide, you will learn how to choose the best block for duplex development services in Perth, so your project becomes a success.

Why the Right Block Matters

The block is the foundation of your duplex. If the block is not suitable, you may face higher costs, council issues, delays, or design limits. A good block helps you build faster, save money and create the layout you want. It also makes your duplex more attractive to buyers or renters.

Check the Block Size

The first thing to check is the size of the land. Each council in Perth has rules for minimum land size for duplex development. These rules are based on the R-Codes (Residential Design Codes). Some R-Codes allow two homes on one block, while others do not.

Things to look for:

• Minimum square metres required

• Whether the block meets R20, R25, R30 or higher

• If the block is large enough for two driveways

• Space for outdoor areas, parking and privacy

  
  

In many Perth suburbs, larger blocks in older areas are perfect for duplex projects.

Check the Block Shape

The shape of the block affects your duplex layout. A clean, rectangular block is easier and cheaper to design. Odd-shaped blocks may need custom house plans, which can cost more.

Best shapes for duplex development:

• Square blocks

• Rectangle blocks

• Blocks with wide frontage

  
  

Long and narrow blocks can work too, but they may limit your design.

Frontage Width

The frontage is the width of the block that faces the street. A wider frontage gives you more room for two homes, driveways and garage access.

Why frontage matters:

• Helps with parking

• Makes it easier to follow council rules

• Allows better natural light for both homes

• Supports modern duplex layouts

  
  

In Perth, many councils prefer duplex homes with separate entrances and clear street access.

Slope and Land Levels

Flat blocks are the easiest to work with. Sloping land may look nice, but it can increase your building costs. You may need retaining walls, extra drainage, or custom engineering.

Before you buy, check:

• If the block slopes forward or backward

• If you need earthworks

• If stormwater flow will affect the design

  
  

A level block helps you build faster and save money.

Zoning and R-Codes

Zoning rules decide what you can build on your block. In Perth, duplex development depends on the R-Code of the area.

Common Perth R-Codes:

• R20 → Usually single homes

• R25 / R30 → Duplex possible

• R40 / R60 → Multi-unit development possible

  
  

Before buying land, always check with the local council or a builder who understands Perth zoning rules.

Crossover and Driveway Planning

Every duplex needs safe and clear access. Some blocks only allow one crossover, while others allow two. This can change your duplex design.

Check for:

• Room for two driveways

• Existing crossovers

• Council limits for crossover size

• Driveway slope

  
  

A good block will make it easy for cars to enter and exit.

Soil Quality

Soil type impacts your foundation cost. Sandy soil is common in Perth and usually easy to build on. Clay or rocky soil can need extra work.

Ask for a soil test to check:

• Soil class (A, S, M, H, E or P)

• If you need extra foundation support

• If the soil may cause movement

  
  

Better soil equals lower cost and fewer problems.

Services and Utilities

A good block should have easy access to services like:

• Water

• Power

• Gas

• Sewer

• NBN

  
  

If these need major upgrades, your project costs will rise.

Location and Suburb Growth

The best duplex blocks are in areas with strong growth, good transport, schools, shopping centres and parks. Perth suburbs with rising demand make duplex homes more valuable.

Look for areas with:

• High rental demand

• Good public transport

• Schools and shops

• Future development plans

  
  

These add long-term value to your duplex.

Council Rules and Approvals

Every council in Perth has its own planning rules. Some councils support duplex development, while others have strict limits.

Before choosing a block, check:

• If a duplex is allowed

• Minimum lot size

• Setback requirements

• Height limits

• Open space rules

  
  

A builder experienced in Perth duplex projects can help you understand these rules.

Check for Easements

An easement is a part of the land used for pipes, drains or cables. You cannot build on easements, which makes duplex planning harder.

Ask for a plan to see if the block has:

• Sewer lines

• Stormwater drains

• Power lines

• Shared access zones

  
  

Blocks without easements offer easier and cheaper duplex design.

Orientation

The direction your block faces affects natural light, heating and cooling. North-facing blocks in Perth are perfect because they give warm winter sun and cool summer shade.

Good orientation helps with:

• Energy efficiency

• Outdoor living

• Light-filled rooms

• Better home design

  
  

Both homes in the duplex should benefit from the block’s orientation.

Budget and Total Costs

Buying the land is only the first step. Always consider the full cost of duplex development in Perth.

Costs to include:

• Land price

• Stamp duty

• Surveys

• Soil test

• Design fees

• Council approvals

• Construction cost

• Landscaping

  
  

A clear budget helps you choose the right block.

Work With an Expert Duplex Builder

The best way to choose the right block is to work with a builder who understands duplex development in Perth. A local builder knows the land rules, council standards, and the best suburbs for growth.

BD Living Pty Ltd can help you:

• Check the zoning

• Study the block

• Avoid costly mistakes

• Pick the best design

• Create a strong investment

  
  

Conclusion

Choosing the right block for a duplex in Perth is one of the most important steps in your project. By checking the block size, shape, zoning, frontage, soil and location, you can avoid problems and build a home that suits your goals. Duplex homes are growing in demand across Perth, and the right block will help you get great value and long-term returns. If you need expert help with duplex development services in Perth, speak with BD Living Pty Ltd, your trusted local builder.