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Scenario

Heritage Statement for a Rear Extension to a Grade II Listed Building

Reviewed by
Oliver Wakefield-Smith
Founder, Digital Signet
Last reviewed 22 June 2026 · Refreshed quarterly
Direct answer
Grade II rear extension , what is required?

A Grade II rear extension typically requires a Statement of Heritage Significance (band 2 to 3, £400 to £1,200). The Statement must identify the contribution the rear elevation makes to overall significance, describe the works in materials terms, and locate the harm on the less-than-substantial spectrum under NPPF ¶208.

Worked scenario
Grade II terraced house, conservation area, single-storey rear extension replacing 1970s lean-to
Sample wording
“The proposed extension replaces a 1970s asbestos-roofed lean-to of no special interest and reinstates a roof line consistent with neighbouring properties. Materials are lime-mortared London Stock brick to match the rear elevation, with a leaded-light timber-framed conservatory addition. The works do not affect the principal elevation, the historic plan-form of the principal rooms or the principal-floor fenestration.”
Likely outcome
Most LPAs grant consent for proposals of this shape on a Grade II terrace where the principal elevation is preserved and the rear addition is subordinate to the original rear-projection ridge.
Mitigation pattern that has won consent
Subordinate massing (single storey, set below the rear-projection ridge), historically-correct materials (lime mortar, matched stock brick, painted timber), and explicit removal of a non-historic eyesore as public benefit.

What to cover in significance

  • Listing entry number, date of designation, list grade.
  • The four heritage values , focus on aesthetic and historical for a terraced townhouse.
  • Contribution to the conservation area where applicable.
  • Identification of any surviving original or historically-correct fabric.

Common reasons LPAs refuse

  • Two-storey extension overpowering the rear-projection.
  • Use of non-traditional materials (uPVC, brick of wrong tone, machine-rolled tiles).
  • Removal of historic rear fenestration without justification.
  • Failure to address the conservation-area s.72 duty where applicable.

Page length and fee

Typically 4 to 8 pages, £400 to £900 ex VAT in 2026 from a competent IHBC or RIBA-CA author. Bundling drawings, photographs and historic-map regression into the same package usually saves 10 to 15% versus instructing separately.