GS Renovation works on lofts and roofs in Kennington, where SE11 is dominated by Georgian and Victorian townhouses, much of it within Lambeth conservation areas. That shapes the answer before anything else: mansards and carefully designed rear additions, not standard box dormers. We coordinate the engineer and architect and manage Lambeth Council building control.
Why SE11 lofts start with the designation
Kennington holds a lot of listed and locally protected Georgian stock, and conservation area designation removes permitted development rights across large parts of SE11. That means a planning application to Lambeth Council for any roof alteration, and listed building consent as well where the property is listed. Repairs and alterations to a listed roof can need consent even when the outside appearance barely changes, which catches people out regularly.
Where a scheme does get through, it is normally a mansard: a steep front slope, a shallow top and detailing that reads as part of the original roof rather than an addition bolted onto it. Mansards add the most usable volume of any loft type and cost the most, indicatively £70,000 to £100,000 or more in London for 2026, before professional fees. We are the contractor and build to the architect's drawings and the engineer's calculations.
Structure, leases and regulations in Kennington
Georgian roofs need respect. Hand-cut timbers, historic alterations and ceiling joists that were never designed to carry a floor all have to be assessed before a design is fixed. The new floor is carried on joists sized by the structural engineer, bearing onto steel beams that span between the party walls onto padstones. In terraced SE11 that steelwork is notifiable under the Party Wall etc. Act 1996, and you serve the notice as building owner.
Many Kennington properties are held on long leases or are flats within a subdivided townhouse, and in those cases the roof space usually belongs to the freeholder. Consent and a lease variation come before planning, and often the answer is simply no. Where a house-wide project does proceed, building control checks the protected stairwell to a final exit, fire doors, alarms, stair geometry, insulation and ventilation.
- L-shaped dormers over a rear closet wing
- Protected stair enclosure and fire doors to Part B
- Building control inspections booked at floor, steel and completion
- Structural steel sized by the engineer and set on padstones
- Rooflight conversions where the roof line must not change
Why Kennington Homeowners Choose GS Renovation
Kennington owners come to GS Renovation because a period roof needs a contractor who understands structure and heritage constraint in equal measure. We coordinate the engineer and conservation architect, install the steels, build the mansard or dormer to their design, prepare your party wall detail and run Lambeth Council building control to completion. Fully insured, with a dedicated project manager throughout.
- Aftercare and snagging support once the job is finished
- Honest answer at survey if your roof will not take a conversion
- Protected stair route and fire doors detailed to Part B
- Waste cleared as we go, not left piled in the garden
- Staircase set out to Part K within the space you have
- Free, no-obligation quotations