Application of Policy CP4 (Affordable Housing) – Part (a) and (e)

In Three Rivers District Council all developments which result in a net gain of a dwelling or are in excess of 1,000sqm trigger the requirement to comply with the requirements of Policy CP4 of the Council’s Core Strategy (adopted October 2011), either by way of the provision of on-site affordable housing or an off-site financial contribution.

Whilst it is recognised that paragraph 64 of The National Planning Policy Framework (2021) (the Framework) states that the provision of affordable housing should not be sought for residential developments that are not major developments, planning applications must be determined in accordance with the development plan unless material considerations indicate otherwise. The Council is of the opinion that its local evidence (Policy CP4 Evidence, link below) is a material consideration of significant weight such that the Framework does not outweigh the weight to be attached to the local evidence of affordable housing need.

The Council’s position in applying in full parts (a) and (e) of Policy CP4 has been heavily supported by Inspectors who continually agree with the approach taken when considering planning appeals.

What approach should I take?

If your development proposal does not constitute major development you will be required to make a valuable contribution towards increasing the number of affordable units in the District by way of an off-site financial contribution. The financial contribution is calculated as set out within the Affordable Housing SPD, expressed as a sum per square meter of the gross internal floor area of the market housing proposed. The sum per square meter is dependent on its location within the District.


Importantly, the sum per metre will be index linked to the Retail Price Index from June 2011 and may, given recent inflation, be a significant amount. If in any doubt, developers should calculate the indexation sum that would be owing in their case at the application stage as it may affect the viability of the development.

 The affordable housing contribution will make my scheme unviable?

As set out within Policy CP4, part (e), affordable housing provision may be subject to viability. Consequently, where a required affordable housing contribution (including indexation from June 2011) would not be viable, a Viability Assessment / Financial Appraisal must be submitted with any application.  This viability information will be assessed by an independent financial advisor, the cost of which shall be borne by the applicant/developer. These costs are from 1 January 2023:

  •  9 units or less: £2,000 plus VAT
  • 10 or more units: Fee to be negotiated on an individual basis depending on whether a Quantity Surveyor (QS) and/or other consultants are required
  • On larger schemes where no QS is involved it is anticipated that the fee would be in the region of £2,500 to £3,000 + VAT
  • On more complicated schemes where the applicant has provided a build cost plan and an independent QS is required to assess it, the cost would be in the range of £1,000 to £2,000 + VAT depending on the complexity of the scheme.

Please note that the relevant fee (payable to Three Rivers District Council for inward transmission) must be paid up-front at the time of validation, and must be a separate payment to the planning application fee.

Viability Assessments should be prepared having regard to the national guidance at and on the basis that it will be made publicly available other than in exceptional circumstances. Even in those circumstances an executive summary should be made publicly available. Please see Validation Checklist for more information

Summary in respect of ensuring your application can be validated:

If you are willing to contribute to affordable housing you must submit at the validation stage either:

 If you are not willing to contribute to affordable housing you must submit:

  • Viability Assessment / Financial Appraisal including relevant fee for its assessment.

Please note any on-site affordable housing mix must have regard to the Council’s First Homes Policy Statement (pdf)