Design Principle pathway (WA R-Codes)

The Design Principle pathway in the WA R-Codes is the assessment route used when a residential proposal misses one or more Deemed-to-Comply (DTC) criteria: the applicant argues that the design still meets the underlying design principle that the DTC criterion was set to achieve. It is the WA equivalent of South Australia’s Performance Assessed pathway and the NSW clause 4.6 variation. The Design Principle pathway is not a separate DA; it’s an argument within the standard R-Codes assessment that allows for design flexibility when the DTC criterion alone is too rigid. Verified per SPP 7.3 R-Codes (2026-05-23).

The DTC vs Design Principle structure

Every R-Codes provision has two layers:

Layer	Description
Deemed-to-Comply (DTC)	Specific measurable criteria (height, setback, plot ratio, open space, parking). Meeting all DTC = compliance demonstrated, council approval routine.
Design Principle (DP)	Qualitative outcome the DTC is designed to achieve (e.g. “amenity to adjoining properties”, “consistent streetscape”, “adequate solar access”).

If you meet all DTC criteria, council approves quickly. If you miss any DTC criterion, you can argue under the corresponding Design Principle that the proposal still achieves the policy’s intended outcome.

When to use the Design Principle pathway

Situation	Pathway
Standard residential meeting all DTC	Stay on DTC; quickest approval
Architectural feature missing one DTC (e.g. extra storey, wider setback)	Design Principle argument
Significant aesthetic choice requiring departure from DTC	Design Principle
Multi-DTC missed but proposal still achieves outcome	Design Principle
Multi-DTC missed AND proposal doesn’t achieve outcome	Refusal likely

What a Design Principle argument looks like

For each DTC criterion missed, the applicant prepares a written argument addressing:

The DTC criterion: state the criterion the proposal misses.
The Design Principle behind it: state what the criterion is trying to achieve.
The proposal’s design response: explain how the proposal achieves the underlying outcome despite missing the DTC criterion.
Supporting evidence: photographs, solar analysis, streetscape drawings, neighbour consultations.

Example: building height exceedance

DTC: maximum 7.5m wall height under R30.
Proposal: 8.5m wall height.
Design Principle: “Buildings present a scale and form sympathetic to the streetscape.”
Argument: surrounding properties are 2-3 storey (street-level survey), the additional 1m of height is partially within the roof envelope, the dwelling is set back further than DTC requires, and adjoining properties’ solar access is preserved (modelled solar analysis attached). Therefore the design principle is met.

Documentation required

A Design Principle application requires more documentation than a straight DTC application:

Document	Purpose
Site plan, elevations, floor plans	Standard
Streetscape photo + drawing	Show consistency with surroundings
Solar access analysis	Demonstrate no adverse impact
Privacy analysis	Demonstrate no overlooking issues
Statement of Design	The written Design Principle argument
Neighbour consultation evidence	Optional but persuasive

Cost and timeline

Pathway	Documentation	Cost (consultant)	Timeline
DTC	Basic plans + checklist	$1,000-$3,000	6-12 weeks council assessment
Design Principle	Plans + extensive design statement	$3,000-$10,000	3-6 months council assessment

The Design Principle pathway typically adds 2-4 months to the DA timeline compared to a straight DTC application.

Decision criteria

When assessing a Design Principle argument, the council/DAP must consider:

Factor	Weight
Does the design achieve the underlying principle?	Primary
Is the impact on neighbours mitigated?	Strong
Is the streetscape consistent?	Strong
Are there cumulative impacts on the precinct?	Moderate
What did neighbours say in consultation?	Moderate
Is the precedent reasonable?	Moderate

A well-argued Design Principle that addresses each consideration has a high success rate. A weak argument that simply asserts “the design is good” without addressing the principle is refused.

Common reasons Design Principle is refused

Refusal reason	What it means
No design statement provided	Application defective; refusal or info request
Statement doesn’t address the principle	Inadequate argument; refusal grounds
Adverse neighbour impact	Solar access, privacy, overlooking
Streetscape inconsistency	Bulk and scale don’t fit
Cumulative precedent	Council fears setting bad precedent
Multiple DTC missed without strong rationale	Departure too significant

Council interpretation varies

A characteristic of the Design Principle pathway in WA is that different councils interpret it differently. A Design Principle argument that succeeds in Subiaco may fail in Cottesloe even with substantially similar proposals. Local political climate, community sentiment, and council planner habit shape outcomes.

For volume builders, building a relationship with the council planning team and understanding their interpretive tendencies is essential.

Comparison to other states

State	Equivalent off-standard pathway
WA	Design Principle pathway (this)
NSW	Clause 4.6 variation under LEP
VIC	Discretionary use under planning scheme
QLD	Code-assessable to impact-assessable upgrade
SA	Code Assessed Performance Assessed
TAS	Discretionary assessment

Pre-DA consultation reduces risk

Pre-DA meetings with the council planning officer are strongly recommended for any Design Principle application. The officer indicates:

Whether the proposal is likely to succeed on the Design Principle pathway.
What aspects to emphasise in the design statement.
Likely neighbour-objection concerns.
Whether additional documentation will be required.

A free 30-minute pre-DA chat can save weeks of back-and-forth during formal assessment.

Builder takeaway

For WA residential at R30+, expect Design Principle arguments for any non-standard design.
Budget $3,000-$10,000 for the design statement consultant.
Add 2-4 months to the DA timeline.
Pre-DA consultation with council reduces risk and clarifies the path.
Neighbour consultation pre-DA is the single best deterrent to objections at the assessment stage.

References

SPP 7.3 R-Codes Volume 1: Design Principles (Department of Planning, Lands and Heritage, WA) (verified 2026-05-23)
Planning and Development Act 2005 (WA) (verified 2026-05-23)