Hounslow W4 · Riverside Listed
Chiswick Mall Windows.
Why Chiswick Mall is different
Chiswick Mall is one of London's finest stretches of Georgian riverside terrace — a continuous run of 18th-century brick houses fronting directly onto the Thames, interspersed with 19th-century additions, all set against a backdrop of one of the city's most photographed riverside walks. The Mall sits within Hounslow Council's Chiswick conservation area, with an unusually high concentration of Grade II and Grade II* listed houses; many properties along the riverside are individually listed.
The combination of listed-building density, river-facing planning sensitivity, and strict heritage character means Chiswick Mall is one of the most exacting environments in London for window work. The headline rule is straightforward: nearly every house here is listed, almost every window change requires Listed Building Consent from Hounslow Council, and Hounslow's heritage team is rigorous about authentic timber, original glazing-bar profiles, and proper riverside-elevation appearance.
What's allowed, what isn't
A practical guide for typical Chiswick Mall Georgian and Victorian listed properties. Always consult Hounslow Council Planning before any works.
| Specification | Riverside / street-visible | Rear elevation |
|---|---|---|
| Like-for-like timber sash, bespoke joinery | Normally approved | Normally approved |
| Slim double-glazed retrofit (existing frames) | Often approved | Often approved |
| Vacuum-glazed retrofit (existing frames) | Often approved | Often approved |
| Internal secondary glazing (reversible) | Approved as reversible upgrade | Approved |
| uPVC visible from street or river | Refused | Refused |
| Modern aluminium frontage | Refused | Refused if visible |
| Frames altering original proportions | Refused | Refused |
| Replacement glazing-bar profiles thicker than original | Refused | Refused |
Recommended specifications
The four routes that consistently survive Hounslow's heritage review on listed Chiswick Mall properties.
| Specification | Best for | Approval pattern |
|---|---|---|
| Bespoke timber sash (Accoya / seasoned hardwood) | Frames beyond economic repair | Reliable approval |
| Slim DGU retrofit (4-8-4mm) into existing sash boxes | Original frames intact | Often approved |
| Vacuum-glazed slim units (~6.5mm) | Original frames, tight reveals | Often approved |
| Internal secondary glazing | Acoustic and thermal upgrade, fully reversible | Heritage-friendly route |
Chiswick Mall window prices
Fitted prices for window works on listed Georgian properties on Chiswick Mall, W4, Q2 2026. All include VAT, frame, glazing, fitting, removal of old window where applicable, and conservation-grade installation. Listed buildings carry no FENSA obligation but require LBC sign-off — we coordinate with the heritage architect on every project.
| Specification | Application | Low | High |
|---|---|---|---|
| Bespoke timber sash, listed property | Front / riverside elevation | £2,400 | £4,500 |
| Slim DGU retrofit (existing frame) | Listed properties | £700 | £1,400 |
| Vacuum-glazed retrofit (existing frame) | Tight original sash boxes | £900 | £1,600 |
| Internal secondary glazing | Acoustic / thermal upgrade | £600 | £1,400 |
| Listed Building Consent application fee | Hounslow Council (2026) | £206 | £206 |
| Heritage architect drawings + statement | LBC submission | £450 | £900 |
Frequently asked
Is Chiswick Mall a conservation area?
Yes — Chiswick Mall and the riverside frontage along the Thames sit within Hounslow Council's Chiswick conservation area designation, with a particularly high concentration of Grade II and Grade II* listed Georgian houses lining the Mall itself. The river frontage adds further sensitivity to any visible alteration. Always consult Hounslow Council Planning before any window work.
Do I need Listed Building Consent on Chiswick Mall?
Most Georgian houses on Chiswick Mall are individually listed Grade II or II*, and any window work on a listed building requires Listed Building Consent (LBC) from Hounslow Council in addition to (or instead of) planning permission. This applies to frame replacement, sealed unit insertion, leaded-light alteration, and even some painting changes. Carrying out works without LBC is a criminal offence under the Planning (Listed Buildings and Conservation Areas) Act 1990.
Can I have uPVC windows on Chiswick Mall?
No — uPVC visible from Chiswick Mall, the Thames Path, or from the river itself is essentially never approved. The concentration of listed Georgian houses, the riverside setting, and the strict heritage character of the Mall mean Hounslow Council heritage officers consistently require timber sash on any visible elevation. Even on rear elevations, where rear gardens are visible from neighbouring listed properties, timber is the safe specification.
What's allowed for windows on a listed Chiswick Mall property?
For listed Georgian properties on Chiswick Mall, the routes most commonly approved by Hounslow Council heritage officers are: (1) like-for-like bespoke timber sash, matching original glazing bar profiles and run-through horns; (2) slim double-glazed sealed units retrofitted into existing sash boxes where the original frames survive; (3) vacuum-glazed slim units (around 6.5mm overall) within original frames; and (4) internal secondary glazing as a fully reversible thermal and acoustic upgrade.
How much do timber sash windows cost on Chiswick Mall?
Bespoke timber sash window replacement for listed Georgian properties on Chiswick Mall costs £2,400–£4,500 per window fitted in 2026. Pricing reflects specialist heritage joinery (Accoya or seasoned hardwood), slim double-glazed or vacuum units, traditional putty glazing where required by the conservation officer, run-through horns, and matching of original sash box and glazing bar profiles. Large oriels, bows, or stained-glass top lights carry further premiums.
Can I install secondary glazing on a Chiswick Mall listed property?
Yes — internal secondary glazing is one of the most heritage-friendly solutions for sash windows on listed Chiswick Mall properties. Modern slim-frame systems are reversible, don't alter the external appearance from the river or the Mall, achieve genuine acoustic improvement against river-side road noise, and typically command a more straightforward Listed Building Consent route. Always confirm with Hounslow Council heritage officers before ordering.
What did original Chiswick Mall windows look like?
Chiswick Mall is one of London's most intact stretches of Georgian riverside terrace, with houses primarily 18th-century with later 19th-century additions. Original windows are typically vertical sliding sashes with thin glazing bars, run-through horns on later examples, and a 6-over-6 or 8-over-8 pane configuration on principal floors. The proportion of glass to frame and the precise width of the glazing bars is what conservation officers most carefully protect.
Who handles the Hounslow Council application?
Apex Glazing surveys the property, prepares like-for-like elevation drawings, and supplies the technical specification needed for a Hounslow Council Listed Building Consent or planning application. The application itself is normally submitted by the homeowner or their conservation architect through the Planning Portal. We coordinate closely with the heritage architects who specialise in Chiswick Mall properties and provide our supporting technical drawings as part of the package.
