Cords and counterweights
Our first choice: cord over a pulley to a weight in the box, balanced by gravity, which never wears out.
Timber sash windows in London
Timber vertical sliding box sash windows, made to order and fitted by our own team across London from our Ruislip showroom.
01Timber windows
What is a box sash window?
Timber sash windows, the window of Georgian and Victorian London, have two sashes sliding up and down, balanced by weights hidden in a box frame. We match the horns and glazing bars a period house needs.
Spiral balances
A slimmer frame for openings with no room for a weight box; plan new springs after 10 to 15 years.
Period detailing
Sash horns, slim glazing bars (often under 18 mm) and the original proportions, for conservation areas that demand like-for-like replacement.
Double glazing in a slim sash
A timber sash takes double glazed units, or vacuum glazing about 8 mm thick where period bars must stay slim.
02Our work
Fitted by our own team.
03Technical specification
Specification.
Every option is confirmed at survey, against your opening and your build stage.
- Window type
- Vertical sliding box sash, two sashes
- Balance system
- Cords and counterweights; spiral balances where a weight box will not fit
- Ventilation
- Both sashes open together, so air enters low and leaves high
- Period detail
- Sash horns and slim glazing bars
- Glazing
- Double glazed units; vacuum glazing, about 8 mm thick, as a thinner option
- Material
- Timber, made to order for each opening
- Sizes
- Bespoke, confirmed at survey
- Fitting
- Supplied and fitted by our own installation team
- Lead time
- Made to order; confirmed with your quote
04Asked before every survey
The questions that matter.
Do I need permission to replace sash windows in a conservation area?
Often yes; your council decides. Replacement usually needs consent, especially under an Article 4 direction, and a listed building needs listed building consent. Rules vary by street, so ask your planning department first. For like-for-like we quote timber with the original horns and slim bars.
Should I repair or replace my sash windows?
Repair if the frame is sound: a sticking or rattling sash often needs only new cords, draught-proofing and a repaint. Replace for rotten bottom rail and cill joints, or for double glazing the old sash cannot take. We say at survey if repair will do.
Cords and counterweights, or spring balances?
Counterweights, unless a roof or wall leaves no room for the box. Gravity does the work, silently, for decades. Spring balances allow a slimmer frame, but the spring tires after 10 to 15 years of use and the sash then knocks, jerks or creeps down.
Can sash windows be double glazed?
Yes. A thinner unit helps where the bars must stay slim, and vacuum glazing, about 8 mm thick, is the thinnest option; ask us if it suits your frames. Heavier glass changes the balance, so the weights are set for your glass.
Do sash windows still rattle and let in draughts?
Not when they are well made and fitted. A modern sash is routed for brush seals in the side channels and compression seals where the two sashes meet, and those stop the whistle and the rattle. We confirm the seal detail with your quote.
05Start here
Start with a conversation.
- A render of the finished result before you commit
- Showroom in Ruislip, opposite Ruislip Manor station, with parking
- One team from survey through to installation
Prefer to talk?+44 20 3375 8609Not ready for prices? Send us a message instead