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Sash Windows. Doors. A More Beautiful Tomorrow

Traditional
Craftsmanship.
Modern Performance.

Handcrafted sash windows, doors and bespoke joinery for period and contemporary homes. Built to last, designed for a more beautiful home.

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Timeless
Homes
Brighter
Tomorrows
◇
Bespoke JoineryCrafted to your specifications
⌁
Energy EfficientModern comfort, timeless style
♢
Heritage ApprovedTrusted for period homes
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Made to MeasureBecause every home is unique
Our Products

Extraordinary Homes Start Here

Beautifully crafted windows, doors and joinery, designed for life.

Timber sash windows

Timber Sash Windows

Authentic style. Superior performance.

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Casement windows

Casement Windows

Versatile. Elegant. Built to last.

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Entrance doors

Entrance Doors

Make a lasting impression.

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Installation and restoration

Installation & Restoration

Repair, renewal and careful joinery detail.

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Why Choose Box Sash

A Higher
Standard by Design

We combine time-honoured craftsmanship with modern innovation to create windows and doors that are as beautiful as they are high performing.

♜
20+Years’ Experience
☆
100%Bespoke Service
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Thousandsof Homes Improved
♡
A GreenerBrighter Future
Sash window hardware detail
The
Details
Make
The Difference
Georgian homeTraditional window interior
Designed Around The House

Joinery should feel as though it has always belonged there.

The best replacement window or door does not announce itself. Its proportions, mouldings, glazing bars, hardware and colour work with the building so naturally that the architecture stays in control.

That is where bespoke matters. The design can respond to a Georgian façade, a Victorian bay, a country kitchen or a cleaner contemporary extension without forcing every property into the same template.

Proportion firstRails, bars, panes and frame widths considered as part of the elevation.
Materials that age wellTimber, glass and ironmongery selected to feel permanent rather than fashionable.
Inside matters tooDeep reveals, light, sightlines and room character inform the finished design.
Made to measureEvery opening is treated as part of an individual home rather than a standard size.
Explore the detailing →
More Than An Opening

Light, proportion and the way a room feels.

Windows and doors change the experience of a home long before you notice their specification. They frame the garden, soften daylight, give a façade rhythm and make old rooms feel composed again.

Traditional sash windows
Period Rooms

Restore the rhythm.

Fine sightlines and traditional proportions bring calm back to tall rooms and bays.

Feature window
Feature Windows

Make light architectural.

Shaped and feature glazing can become part of the architecture rather than an afterthought.

French doors
Garden Connection

Open the house gently.

French doors keep the proportions traditional while bringing the garden into the room.

Featured Projects

Homes We’re Proud Of

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Georgian townhouse sash-window façade

Georgian Townhouse

London · Sash-window façade→
Victorian family home

Victorian Family Home

Surrey · Period stone exterior→
Period renovation

Period Renovation

Cotswolds · Garden-facing kitchen→
Windows In The Home

Not just façades. Rooms, views, hardware and the spaces between.

A more complete window story: the way the joinery looks from the street, how it frames a room and how the details feel up close.

Period bay windows
Casement windows in a kitchen
Heritage window interior
Georgian window
Restored window exterior
Black entrance door
Entrance Doors

The front door is part of the façade, not an accessory.

Panel proportions, glazing, fanlights, colour and ironmongery all contribute to the architecture of the entrance.

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French doors opening to a garden
French Doors · Paired glazed doors opening onto the garden
Timber bi-fold doors
Bi-Fold Doors · Folding timber panels opening the kitchen to the terrace
The Final Five Percent

The small choices are what make bespoke joinery feel properly considered.

Colour, hardware, glass and moulding profiles should support the house rather than compete with it. The finish is where the technical product becomes part of the interior and the façade.

Traditional brass sash fastener

Ironmongery

A traditional brass sash fastener, selected to sit quietly against painted timber.

Muted sage painted entrance door

Paint Colour

A muted sage entrance shows how colour can change the character of a façade without overpowering it.

Timber window components and brass hardware on a joinery bench

Craft & Profiles

Timber sections, window components and hardware are resolved together as one piece of joinery.

Large circular feature window

Feature Glazing

A circular window turns glazing into an architectural feature, framing both light and the view.

From House To Joinery

A measured process, not a catalogue purchase.

The right result comes from understanding the building first, then developing the design, material and finish around it.

01
SurveyUnderstand the openings, the architecture and what needs to improve.
02
DesignAgree proportions, configuration, detailing, glass, colour and hardware.
03
CraftTurn the specification into made-to-measure timber joinery.
04
InstallFit the finished joinery carefully so it reads as part of the house.
Joinery craftsmanship
Designed to be noticed less.Profiles, timber components and hardware are resolved together before the finished joinery reaches the house.
Customer Reviews

Five-star words from real Box Sash customers.

These cards use the customer’s exact wording. Longer reviews are shown as short verbatim excerpts with a link to the original Trustpilot page.

★★★★★

“Professional service and excellent product. OBSW were able to specify windows that other companies said were impossible.”

Edward Christie5★ Trustpilot · November 2025 · Exact excerpt
★★★★★

“No hesitation in recommending them.”

Bill Swan5★ Trustpilot · March 2025 · Exact excerpt
★★★★★

“the fitting was done efficiently and neatly, and the windows are well-constructed and draught-free.”

Tony Roth5★ Trustpilot · February 2022 · Exact excerpt
★★★★★

“Amazing quality and service. Really so happy with them, thanks!”

Arianna5★ Trustpilot · October 2021 · Exact excerpt
★★★★★

“The windows are stunning- excellent quality and the installation was so smooth and straight forward. We were thoroughly impressed.”

Jill Benjoya Miller5★ Trustpilot · January 2021 · Exact review
★★★★★

“Excellent all the way through. Good product and excellent customer service throughout the whole process Can't recommend them enough.”

Mrs Carpenter5★ Trustpilot · December 2020 · Exact review
★★★★★

“Brilliant company with very helpful workers who ask what you want and then do just that.”

Mr Papas5★ Trustpilot · January 2018 · Exact review
★★★★★

“All round great service”

Mrs K Prest5★ Trustpilot · May 2016 · Exact review
★★★★★

“Very helpful throughout and the installer left the room spotless. Very pleased.”

Alison H5★ Trustpilot · May 2016 · Exact review
★★★★★

“Everyone was very friendly and helpful and I am delighed with the windows/”

Mrs Cohen5★ Trustpilot · November 2014 · Exact excerpt

Verbatim excerpts from public five-star Trustpilot reviews. Some longer reviews are shortened rather than reproduced in full; wording shown inside quotation marks is unchanged.

Read the full reviews on Trustpilot →
Start With The House

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