Section 4.55 Modification NSW — Modify Your Approved DA

When to use Section 4.55

Common situations where 4.55 is the right pathway:

• Adjusting setbacks, window positions or rooflines after DA approval
• Modifying internal layouts without changing external envelope
• Changing materials, finishes or specifications
• Reducing the approved development (smaller footprint, fewer storeys)
• Updating BASIX commitments to reflect new thermal performance solutions

Use a fresh DA instead when the modification would make the development 'substantially different' — e.g., changing the use, doubling the floor area, or fundamentally altering the streetscape impact.

Modification costs and timeline

Our 4.55 process

1. Feasibility assessment: we review your original consent, proposed changes, and advise whether 4.55 is viable
2. Documentation: modified plans, Statement of Environmental Effects amendment, BASIX (if affected)
3. Lodgement: via NSW Planning Portal as your agent
4. Follow-up: RFI responses through determination

Frequently Asked Questions

Can I modify my development after DA approval in NSW?

Yes — under Section 4.55 of the NSW Environmental Planning and Assessment Act 1979, you can apply to modify an approved development. Minor changes (s 4.55(1)) are usually quick; larger changes (s 4.55(2)) require a full modification application. Construction Certificates can also be amended after issue.

What's the difference between Section 4.55 and 4.56 modifications?

Section 4.55(1) covers minor modifications that don't substantially alter the approved development. Section 4.55(2) covers more substantial modifications but is still cheaper and faster than a fresh DA. Section 4.56 applies to modifying Development Consents issued by the Land and Environment Court.

How long does a Section 4.55(2) modification take?

Most councils take 4–8 weeks to assess a 4.55(2) modification. Minor s 4.55(1) modifications are often quicker (2–4 weeks). Complex modifications or those triggering further environmental assessment may take longer.

How much does a 4.55 modification application cost?

Council fees for s 4.55(2) modifications are typically $400–$1,500 depending on council and original DA cost. The larger cost is architectural documentation for the modified design, usually $1,500–$5,000 depending on the scale of changes.

When should I do a 4.55 application instead of a new DA?

Use s 4.55 when your change doesn't fundamentally alter the approved development — e.g., changing window positions, adjusting setbacks slightly, modifying internal layouts, or reducing the approved footprint. Use a fresh DA only when the scope changes so much that the original consent is 'substantially different'.

Can council refuse a 4.55 modification?

Yes — if the modification would cause the development to be 'substantially different' from the originally approved development, or if it raises new environmental impacts not previously assessed. We assess viability before lodging to manage this risk.