Section 73 Planning Applications: Amending Planning Conditions in NW3

Introduction

Once planning permission has been granted, it is not always the end of the planning process. Conditions attached to a permission may need to be varied — perhaps a pre-commencement condition cannot be discharged in the way originally envisaged, or circumstances have changed since the permission was granted. A Section 73 application (under Section 73 of the Town and Country Planning Act 1990) allows a planning permission to be modified — specifically, to vary or remove conditions — without surrendering the original permission. This guide explains when and how to use Section 73 in the context of NW3 projects. For related guidance, see our planning conditions discharge guide, retrospective planning guide and Camden planning guide.

What Section 73 Does

Section 73 of the TCPA 1990 allows a planning authority to grant planning permission for development without complying with conditions subject to which a previous planning permission was granted. In practice, this means:

• You can apply to vary a condition (e.g. changing a materials condition that requires using a specific product to allow an alternative)
• You can apply to remove a condition that the planning authority agrees is no longer justified
• The Section 73 grant creates a new planning permission — running alongside (not replacing) the original permission. Both permissions then exist; the developer can choose which to implement.

What Section 73 cannot do:

• It cannot vary the description of development itself (only conditions)
• It cannot be used to make fundamental changes to the scheme beyond what the original permission describes
• It cannot remove the time limit condition requiring commencement within 3 years

Common Uses of Section 73 in Domestic Projects

Section 73 applications arise in NW3 domestic projects in several typical scenarios:

• Materials variation: A planning condition requires approval of external materials before construction commences. The applicant proposes a specific brick in the discharge application, but the brick is unavailable or the supplier has changed the specification. A Section 73 application can vary the materials condition to permit an alternative that achieves a similar appearance.
• Design changes identified during technical design: A planning permission was granted for a scheme at design stage. During technical design (RIBA Stage 4), minor amendments to the design emerge — a window is repositioned, a parapet height adjusted. If these changes are minor and do not alter the fundamental character of the approved scheme, a Section 73 application can regularise them without a new full application.
• Extending the time limit: A standard planning permission expires 3 years from the date of approval. If a project has not started within 3 years (typically for reasons of finance, other planning complications, or construction market constraints), a Section 73 application to vary the commencement condition — effectively granting a new permission with a fresh 3-year clock — is possible. However, this is subject to the planning policies current at the date of the new application, which may have changed.
• Hours of construction conditions: For larger projects in NW3, Camden often imposes conditions on hours of construction to protect neighbours. A Section 73 application can seek to amend these hours in justified circumstances.

The Section 73 Application Process

A Section 73 application is submitted in the same way as a standard planning application, using the Planning Portal. The application includes:

• The application form, identifying the original planning permission and the specific condition(s) to be varied
• An explanation of why the variation is sought and why it is appropriate
• Any supporting drawings, specifications or documents required to evaluate the variation
• The standard planning fee (householder application fee applies to domestic Section 73 applications)

The planning authority determines the Section 73 application using the same process as a new planning application. Because a new permission is created, all development plan policies current at the date of the Section 73 decision apply — this can occasionally create complications if policies have changed significantly since the original permission.

Non-Material Amendments: The Alternative to Section 73

For very minor changes to an approved scheme — adjusting a dimension by a small amount, repositioning a drain, minor changes to internal layouts — a Non-Material Amendment (NMA) application under Section 96A of the TCPA 1990 may be more appropriate than a Section 73. An NMA is faster (typically 28 days rather than 8 weeks) and involves no fee. However, the threshold for "non-material" is genuinely minor — if in doubt, a Section 73 application provides more certainty. See our planning conditions guide.

Conclusion

Section 73 applications are an important and underused tool for homeowners navigating the post-permission stages of a project in NW3. They allow planning conditions to be varied to reflect changed circumstances, design development, and material substitutions — without losing the benefit of the original planning permission. An architect who manages the planning process actively, including post-permission amendments, will use Section 73 where appropriate to keep a project on track. Use our free matching service to find an architect experienced in Camden's planning framework. For project cost guidance, visit hampsteadrenovationcosts.co.uk.