London Borough of Southwark
Timber Sash Windows Dulwich
Heritage and conservation specialists serving Dulwich Village, West Dulwich and all Southwark conservation areas
Dulwich Village is one of south London's most carefully protected heritage environments, a designated conservation area within the London Borough of Southwark, centred on the historic village core with its Georgian and early Victorian architecture and the Dulwich Estate which manages much of the surrounding housing stock. Many properties in and around Dulwich Village are Grade II listed, with original box sash windows that require like-for-like replacement under Listed Building Consent.
The area's housing stock ranges from the Georgian terraces and detached villas of the village core to the large late-Victorian and Edwardian detached houses of West Dulwich and Herne Hill. Sash windows are the predominant window type throughout, and Southwark's conservation officers expect replacements in timber with matching profiles, glazing bar sections and proportions. Our survey identifies the correct specification for each property before any work begins.
Sash window specifications for Dulwich homes
Conservation areas we cover in Dulwich
- Dulwich Village
- West Dulwich
- Herne Hill
- East Dulwich
- College Road
- Burbage Road
- Lordship Lane
- Crystal Palace
Why Dulwich requires a specialist
The Dulwich Estate manages a significant proportion of the housing in and around Dulwich Village and requires estate consent for external alterations, including window replacements, on estate-managed properties. This is separate from and in addition to Southwark Council planning requirements. Leaseholders on the estate typically need both estate approval and planning consent before work can begin. Our survey identifies which consents are required for each property.
For listed buildings in Dulwich Village, Listed Building Consent requires like-for-like replacement with solid framed glazing bars, putty-fronted glazing and authentic timber sections. We provide LBC drawings and specification documentation to support the application, and advise on vacuum glazing where the heritage officer requires the thinnest possible glazing unit.
Sash window questions from Dulwich homeowners
Do the Dulwich Estate rules apply as well as Southwark planning?
In much of Dulwich, yes. Properties on Dulwich Estate land carry a scheme of management, so window changes need the Estate's consent alongside Southwark planning permission where the property is in a conservation area. The two run in parallel and ask for similar evidence, so we prepare one drawing set that satisfies both.
What is required in Dulwich Village conservation area?
Southwark expects replacement sashes to match the original in material, glazing bar section and pane proportion. On the Georgian and early Victorian houses along Dulwich Village and Calton Avenue that means solid framed bars and a putty-line finish, with slimlight or vacuum glazing rather than a standard double-glazed unit.
Can you match the Edwardian sashes in West and East Dulwich?
Yes. The Edwardian and late-Victorian stock around Lordship Lane, Court Lane and Turney Road often has one-over-one or margin-light sashes with horns. We copy the horn shape, bar section and meeting rail depth from the existing window so a single replaced window is not obvious next to the originals.
Do you repair existing sash windows?
No. We make and install new timber sash windows. Where Southwark or the Dulwich Estate is unlikely to approve full replacement, we can keep the existing box frames and fit new made-to-measure sashes, which retains the original joinery both look favourably on. We set out the options with prices after the survey.
How long does the whole Dulwich process take?
Typically four to eight weeks for Southwark and Estate decisions, eight to ten weeks manufacture, then a few days on site. We can start manufacture on unaffected elevations while a decision is pending if you want to compress the programme.
Nearby areas we cover
More timber windows for Dulwich homes
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