From the team behind Hampstead Renovations · Est. 2009 · Learn more
Case StudyHampstead Garden Suburb, NW11April 2025

Loft Conversion, Hampstead Garden Suburb

A rear dormer loft conversion to an Arts & Crafts semi-detached house in Hampstead Garden Suburb, one of only a small number approved in the Suburb in recent years. The project required both Barnet Council planning permission and Hampstead Garden Suburb Trust consent — a dual consent process unique to the Suburb.

Project Type

Dormer Loft Conversion

Duration

14 weeks

Project Value

£78,000

The Challenge

Hampstead Garden Suburb operates a unique dual consent system: both Barnet LBC planning permission and Hampstead Garden Suburb Trust consent are required for any material alteration. The Trust's design committee has refused many loft applications on grounds of visual impact on the Suburb's special character. The property's Arts & Crafts roof featured complex clay tile detailing that had to be matched exactly.

Our Solution

We appointed an architect with direct experience of the HGS Trust design committee's requirements — only a handful of practices have track records of Trust consent for loft conversions. The dormer was designed as a minimal rear element set entirely within the rear roofslope, with traditional clay peg tiles matching the existing roof exactly. Both Barnet and Trust consents were obtained in 11 weeks.

Results

  • Both Barnet LBC planning and HGS Trust consent obtained in 11 weeks
  • Clay peg tile dormer matching existing roof material exactly
  • 28m² of loft space created
  • Double bedroom with en-suite shower room
  • Velux rooflights to rear pitch — Trust-approved positions
  • New staircase incorporating bespoke fitted library shelving
  • Estimated property value uplift: £140,000

Key Features

  • HGS Trust dual consent — Barnet LBC and Trust approval
  • Clay peg tile dormer — exact match to existing Arts & Crafts roof
  • Minimal rear design within roofslope — no street impact
  • Double bedroom with fitted joinery
  • En-suite shower room with Hansgrohe fittings
  • Staircase with integrated bespoke library shelving

Specification

ItemSpecification
Dormer roof tilesKeymer clay plain peg tiles, Cottage blend, matching existing roof — sourced from same manufacturer
Dormer structureTimber-frame dormer with breathable membrane, 100mm PIR insulation, slate-effect felt
RooflightsVelux Conservation GGL triple-glazed, two units, HGS Trust-approved rear positions
En-suiteHansgrohe Croma Select thermostatic shower, Porcelanosa wall tiles, Duravit basin and WC
Library shelvingBespoke painted hardwood shelving on staircase spine wall, adjustable shelf pins
InsulationKingspan Thermaroof TR27 PIR between and below rafters, achieving U-value 0.16

Interested in a similar project?

We work across all of NW London. Get a free, no-obligation quote for your project.