GS Renovation builds loft conversions in Teddington, on the Victorian and Edwardian terraces and larger period houses set back from the river. Ridge heights are usually good in TW11, and conservation designation decides the roof form. We coordinate the engineer, build the structure and run Richmond Council building control to certificate.
Choosing a form for a TW11 house
A Teddington terrace with its rear closet wing intact takes an L-shaped dormer, the arrangement that produces a double bedroom and an en suite rather than one room under a slope. The larger semi-detached and detached period houses, many with a hipped or half-hipped roof, gain more from a hip to gable with a dormer behind it. Both need the same starting measurement, roughly 2.2m to 2.4m from the top of the ceiling joists to the underside of the ridge.
Where a house sits inside one of Richmond's conservation areas, and a fair number of TW11 streets do, permitted development rights are removed and the design has to be one an officer will support. That usually means a mansard, dormers in a traditional proportion, or conservation rooflights. Indicative London ranges for 2026 run roughly £55,000 to £80,000 for an L-shaped dormer or a hip to gable, and roughly £70,000 to £100,000 or more for a mansard.
Fire, structure and Richmond Council
Turning a two-storey house into a three-storey one changes the fire strategy, and that is the part homeowners rarely expect. Part B normally calls for a protected stairwell running from the new floor all the way to a final exit, with fire doors to the rooms opening off it and interlinked alarms throughout. Where an open plan ground floor makes that impossible, the alternatives are a sprinkler system or a protected escape route agreed with building control, and settling it at design stage costs far less.
The structure itself is straightforward when it is done properly. The engineer sizes steel beams to span between the party or flank walls, carrying the new floor joists and the dormer above, bearing on padstones set into the brickwork. The old water tank comes out. Richmond Council building control inspects at stages and issues the completion certificate, and where a wall is shared the Party Wall etc. Act applies, with notice served by you as building owner.
- Head height and ridge survey before design
- Dormer cheeks, flat roof and leadwork detailed to last
- Insulation between and over rafters to Part L
- Structural steel sized by the engineer and set on padstones
- Hip to gable conversions on semi-detached and end terrace roofs
Why Choose GS Renovation in Teddington
Teddington owners choose GS Renovation because the fire strategy, the stair and the steelwork are where a loft conversion is won or lost, and those are our strengths. We coordinate the engineer, build to the design and take Richmond Council building control to certificate. Founder Abdelaaziz Saaid brings 30+ years of hands-on structural work. We are fully insured and every quotation is free.
- One point of contact on the phone, not a call centre
- Free, no-obligation quotations
- Staircase set out to Part K within the space you have
- Water tank removed and the system converted where it blocks the space
- Structural engineer instructed and coordinated on your behalf
- Paperwork and certificates handed over for when you sell