GS Renovation converts lofts across Edgware, on the interwar semis and detached houses that fill HA8. Hipped roofs and wide plots make hip to gable with a rear dormer the natural choice on most of these streets. We coordinate the structural engineer, build the gable and the steelwork, and run Barnet Council building control.
Getting a full storey out of an HA8 roof
The suburban semi was built with a hipped roof on the side elevation, and that hip is why so many Edgware lofts feel cramped when they are done cheaply. Rebuilding the hip as a vertical gable squares off the plan and gains a metre or more of standing height across the width, and a dormer on the rear slope then supplies the flat ceiling area a bedroom, a landing and a shower room actually need. Detached houses in HA8 can sometimes take the same approach on both flanks.
Where the roof is trussed rather than traditionally cut, which happens on the later infill housing, the trusses have to be replaced with a structural frame before anything is habitable, and that shows in the price. The engineer sizes the beams and the new floor joists and we build to that design. Indicative London ranges for 2026 put hip to gable with a rear dormer at roughly £55,000 to £80,000, with a shower room or en suite adding roughly £8,000 to £15,000.
Barnet Council, party walls and sign-off
A semi-detached or detached house carries the larger commonly cited volume allowance of 50 cubic metres, and a lot of Edgware conversions sit inside it. The conditions are strict: nothing forward of the existing roof plane, materials to match, no verandas or balconies, and any side-facing window obscure glazed and non-opening below 1.7m. Permitted development is withdrawn on listed buildings, in conservation areas and under an Article 4 direction, so we confirm the position with Barnet Council rather than assume it.
Building on the shared wall of a semi is notifiable under the Party Wall etc. Act 1996, whether that is a new gable, a steel bearing or a dormer cheek. As building owner you serve the notice on your neighbour, and we prepare the drawings and details a surveyor will ask for. Barnet building control then inspects in stages: the steel and floor, the fire strategy under Part B with a protected stair and interlinked alarms, the stair itself under Part K, and the insulation before anything is boarded out.
- Rooflight conversions where the roof line must not change
- Mansard conversions where planning will not accept a dormer
- Velux and conservation rooflights fitted and flashed
- Hip to gable conversions on semi-detached and end terrace roofs
- Head height and ridge survey before design
Why Edgware Homeowners Choose GS Renovation
Edgware owners choose GS Renovation because building a gable and dropping steel into a semi is structural work, and structural work is the core of the business. One team runs the engineer, the roof, the stair, the en suite and Barnet Council building control. Founder Abdelaaziz Saaid has 30+ years of hands-on building experience behind him, and we are fully insured and quote free of charge.
- Honest answer at survey if your roof will not take a conversion
- Building control applications and inspections coordinated for you
- Founder-led team with 30+ years of hands-on experience
- Ridge height measured before any design work is commissioned
- Protected stair route and fire doors detailed to Part B
- Materials priced at options, so you choose the finish