Sash Window Repair Mayfair | Hartwell Sash
Sash Window
Repair in
Mayfair
Period property specialists serving Mayfair, Marylebone, St James's and Fitzrovia — repair, restoration and glazing upgrades done properly.
Scroll down to see what we doGeorgian townhouses, mansion flats —
windows worth preserving
Mayfair and the surrounding W1 postcodes contain some of London's most valuable and historically significant residential property. Georgian townhouses, elegant mansion flats and discreet mews houses define an area where original architectural detail — including sash windows — is carefully preserved.
Around Grosvenor Square, Berkeley Square, Hill Street and the streets running through Mayfair, original sash windows remain a defining feature — often tall, well-proportioned, and worth restoring carefully rather than replacing.
Much of Mayfair sits within Conservation Areas and contains many listed buildings. Original sash windows are integral to the character of these properties — and replacement work may require consent and should be checked before proceeding.
What we do —
done properly
Every service carried out with care and precision
Draught Proofing
Cold draughts and outside noise reduced significantly — without changing the appearance of your windows. We replace staff bead and parting bead with precision brush pile seals and fit a brush seal at the meeting rail.
Sash Cord Replacement
Windows that slam shut or won't stay open — fixed properly. We replace both sash cords on both sides and rebalance both sashes as standard. One visit, done properly.
Glass Replacement
Cracked, broken or misted panes replaced carefully — preserving the original timber frame. Heritage glass available for Conservation Areas throughout Mayfair.
Timber Repair & Repainting
Rotting timber repaired, not replaced wherever possible. The tall Georgian sash windows found throughout Mayfair often suffer from paint build-up at the meeting rail, failing cords and swollen frames — the result of years of deferred maintenance in high-value properties. We work carefully to restore rather than replace, preserving the original timber wherever possible.
Slimline Double Glazing Upgrade
Upgrade single glazing to slimline double glaze units — fitted within the existing frame, preserving the original look entirely. Better insulation, less noise, no change to the character of your property.
Full Sash Replacement
When a window is genuinely beyond saving — we supply and fit heritage timber sash windows made to match the original design of your property. Not uPVC. Timber, made properly.
"Nick replaced broken sash cords quickly and efficiently. Very tidy work — wouldn't hesitate to book again."
"Outstanding craftsmanship. You can tell this is done by someone who really cares about the work."
"Clear communication and fast work — exactly what you want. Arrived on time, left everything spotless."
Working in
Mayfair's
protected streets
Much of Mayfair sits within Conservation Areas administered by the City of Westminster. There are many listed buildings across Mayfair and the wider W1 area — and any work affecting their appearance requires careful consideration.
In many cases, draught proofing, cord replacement and careful like-for-like repairs can be carried out without changing the appearance of the window. For listed buildings, flats, replacement work or properties under specific restrictions, we always recommend checking the correct consent requirements before work begins.
Free survey
in Mayfair
We visit your property, assess every window and give you an honest quote — no call-out fee, no obligation, no pressure. We aim to respond the same day.