Designers & Craftsmen of Beautiful Sash Box Windows in London

Call us now for a free survey on 0203 004 9876


We have specialist expertise in the design and manufacture of traditional or modern box, sash and casement windows to your specification. We can replace existing windows on a like-for-like basis including wooden sliding box sash windows, bay windows and replacement window frames. We can supply you with made-to-measure quality timber windows to fit in existing openings and are also able to upgrade older window frames with new moving parts.

Our timber sash windows are all custom made. We can make replacements of original period design, even if you live in a conservation area or own a listed building. You can choose from weight or spring assisted sash windows, depending on your budget.

All our windows exceed British Standard criteria for strength and weather resistance. They also exceed the new government standards for energy efficiency (known as U-values) which are enforced by FENSA.
Visit the FENSA website for more about U-values

Our weight assisted sashes replace the original lead weight and pulley windows fitted in most Georgian and Victorian houses. These stunning windows accurately replicate the originals with details including the original bars, curves, horns and frame dimensions.

Using a spring balance opening mechanism offers a great value alternative to lead weight and pulley sashes, without compromising on the quality. There is a substantial saving to be made in cost, with little visible difference to the sashes. This is a great way to make quality sash windows more affordable. 

Listed buildings and certain conservation areas insist that the design and materials of existing windows must be retained in the new ones. We are able to produce windows that conform to these requirements and help with the design and application process.

All our box sash windows are crafted by hand in the traditional way and will meet your full expectation. These beautiful bespoke windows bring classic looks to even the most modem building.

Whether working on Listed Buildings, refurbishments or new-build properties, we are able to match any window or provide any new design to architect specification.

We are happy to supply any client, whether trade, professional or private customer.

APT can match any existing window pattern and provide new windows that are highly energy – efficient and environmentally friendly. Far more attractive than UPVC, these windows are made in either softwood or hardwood.

Sash windows come with cords, pulleys and weights or spring-balance mechanisms, and are delivered either in a primed finish, a natural finish or can be spray-painted to order. They can be single, double, double or triple-glazed as required. All are fully draught-proofed. Mouldings can be specified as required.

Given the extensive experience of our joinery team and using the finest woods available, you will find we provide the ideal service – whether you’re a builder, professional or private home owner.

APT team are always happy to hear your thoughts about your project, either on the phone or in person.

If you’d like to know more please arrange a Complimentary no obligation site visit at your property.

Call Us: 0203 004 9876

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Office Opening Hours

Mon        08:00 – 17:00
Tue         08:00 – 17:00
Wed        08:00 – 17:00
Thu         08:00 – 17:00
Fri           08:00 – 17:00

Outside of these hours, please leave a message and we will call you straight back.

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