Twickenham TW1 · Listed Buildings
Strawberry Hill Windows.
Why Strawberry Hill is different
Strawberry Hill is the birthplace of British Gothic Revival. Horace Walpole began transforming his villa into a "little Gothic castle" in 1749, decades before Pugin or Ruskin. The villa itself is listed Grade I, and a substantial proportion of the surrounding streets in TW1 sit within the Strawberry Hill Conservation Area, with multiple Grade II and Grade II* listings clustered along Waldegrave Road, Strawberry Vale, Tower Road and the immediate setting of the house.
For window work, the headline rule is straightforward: if your property is listed, Listed Building Consent is required for any frame replacement or material change — full stop. Carrying out works without LBC is a criminal offence under the Planning (Listed Buildings and Conservation Areas) Act 1990. Conservation area status alone does not require LBC for windows on non-listed properties, but an Article 4 Direction may still apply, and Richmond Council's heritage team takes a careful view of any change visible from the public realm.
What requires Listed Building Consent
The threshold for LBC is "any works which would affect the special architectural or historic interest" of the listed building. In practice that captures essentially all window work on a listed property — exterior or interior. The list below is illustrative, not exhaustive — always consult Richmond Council Planning before any changes.
| Works | LBC required? |
|---|---|
| Replacement of timber sash with new timber sash | Yes |
| Insertion of double-glazed units in existing frames | Yes |
| Replacement of leaded lights or quarries | Yes |
| Repainting in a different colour | Yes (often) |
| Repair-in-place using like-for-like timber sections | Often yes — confirm with officer |
| Internal secondary glazing (reversible) | Sometimes — confirm with officer |
| Removal of historic Crittall metal frames | Yes |
What's normally approved
When LBC is granted at Strawberry Hill, the approval almost always rests on one or more of the following sympathetic specifications.
| Specification | Why it works |
|---|---|
| Like-for-like bespoke timber, matching original profiles | Preserves architectural character |
| Slim double-glazed units (4-12-4mm) in new heritage frames | Sealed unit hidden behind original glazing-bar reveals |
| Vacuum-glazed retrofit (~6.5mm) into existing sash boxes | Original fabric retained, U-value dramatically improved |
| Crittall restoration (refurbish rather than replace) | Conservation officer's preferred approach for historic metal |
| Leaded-light replication using traditional cames | Geometric quarries, hand-pulled glass where specified |
| Internal secondary glazing (reversible system) | Reversible, no impact on external appearance |
For non-listed properties within the conservation area, Smart Aluspace SR is a Crittall-replica steel-look aluminium system used for new builds, rear extensions, and modern interventions. It will not be approved as a replacement for any historic Crittall on a listed building.
Strawberry Hill window prices
Fitted prices for window replacement in Strawberry Hill TW1, Q2 2026, including specialist heritage joinery for listed properties. All include VAT, frame, glazing, fitting, removal of old window, and FENSA self-certification (Reg 40373) where applicable. Listed buildings carry no FENSA obligation but require LBC sign-off.
| Specification | Application | Low | High |
|---|---|---|---|
| Bespoke timber sash, listed property | Grade II / II* listed | £2,400 | £4,500 |
| Vacuum-glazed retrofit (existing frame) | Listed properties | £700 | £1,400 |
| Leaded-light replication | Gothic Revival originals | £1,200 | £3,200 |
| Crittall restoration (refurbish) | Historic metal frames | £900 | £1,800 |
| Smart Aluspace SR (non-listed) | Conservation-area new build | £1,200 | £2,400 |
| Internal secondary glazing | Listed, reversible | £600 | £1,400 |
| Listed Building Consent application fee | Council fee (2026) | £206 | £206 |
| Heritage architect drawings and statement | LBC submission | £450 | £650 |
Frequently asked
Do I need Listed Building Consent for windows in Strawberry Hill?
If your property is listed Grade I, II*, or II, any change that affects the special architectural or historic interest — including window replacement, alteration of glazing bars, replacement of leaded lights, or even painting in a different colour — requires Listed Building Consent (LBC) from Richmond Council. LBC is a separate application from planning permission and the two are usually run in parallel. Carrying out works to a listed building without LBC is a criminal offence under the Planning (Listed Buildings and Conservation Areas) Act 1990.
Can I get double glazing in a listed Strawberry Hill home?
Often yes, but it requires Listed Building Consent and a sympathetic specification. Slim double-glazed units (typically 4-12-4mm overall around 14mm) within new timber frames matching the original profile, or vacuum-glazed retrofits at around 6.5mm overall fitted into existing sash boxes, are the two routes Richmond Council heritage officers most commonly approve. Replacement frames thicker than the original or visible black spacer bars are usually refused on principal elevations.
How long does Listed Building Consent take in Richmond?
The statutory determination period for a Listed Building Consent application in England is 8 weeks from validation. In practice, well-prepared LBC applications in Richmond are typically determined within 8–12 weeks. Complex schemes affecting Grade I or II* listings, or applications requiring consultation with Historic England or the Twentieth Century Society, can take longer. Pre-application advice from Richmond Council typically returns within 4–6 weeks.
What did original Strawberry Hill windows look like?
Horace Walpole's Strawberry Hill House, built from 1749 onwards, is the seminal early example of Gothic Revival domestic architecture in Britain. Original windows include pointed-arch lancets, quatrefoil openings, and leaded lights with diamond or geometric quarries set in lead cames. Surrounding 19th and early 20th century houses in the conservation area carry on Gothic, Tudor, and Arts & Crafts vocabularies — leaded lights, oriels, and ornamental glazing patterns are common.
How much does Listed Building Consent cost?
As of 2026 the application fee for Listed Building Consent in England is £206 (set by national regulations and updated periodically — verify current rates with Richmond Council). Add £450–£650 for elevation drawings and a Heritage Statement from a conservation architect, plus optional pre-application advice fees if you take the recommended route of an officer pre-app before formal submission.
How much do timber sash windows cost for a Strawberry Hill listed property?
Bespoke timber sash window replacement for listed properties in Strawberry Hill costs £2,400–£4,500 per window fitted in 2026, with bespoke Gothic Revival arched lights and leaded glass restoration carrying a premium. Pricing reflects hardwood joinery (Accoya or seasoned oak), slim double-glazed or vacuum units, run-through horns, traditional putty glazing, and matching of original glazing bar profiles. Specialist heritage joinery is the dominant cost driver.
Can I install Crittall-style windows in Strawberry Hill?
Restoration of original Crittall metal windows in non-listed properties within the conservation area is generally encouraged. For new installations on non-listed properties, a Crittall-replica steel-look aluminium system such as Smart Aluspace SR is normally accepted on rear elevations and modern extensions. On listed buildings, retention and refurbishment of any historic Crittall fabric is the conservation officer's preferred outcome — replacement of historic Crittall would require detailed LBC justification.
Is the whole of Strawberry Hill a conservation area?
Yes — the Strawberry Hill Conservation Area is designated by Richmond Council and covers Strawberry Hill House and a substantial cluster of surrounding streets in TW1. Many individual properties within the conservation area are also listed; Strawberry Hill House itself is listed Grade I. Conservation area status alone restricts demolition and protects trees; listing layers a much stricter consent regime on top of that for individual buildings.
