Double Glazed Timber Sash Windows


Thermal & acoustic insulation as well as increased security are some of the key benefits that double glazing offers. For many period home owners replacement uPVC or metal double glazed windows are an unacceptable option as they detract from the authentic charm of the property. At Barnsbury Joinery Co. we understand the need to incorporate modern advances into period homes without significantly altering the appearance.

We supply & install authentic wooden replica sashes into existing timber frames, paint finished and double glazed with energy efficient (low E) glass. In some cases it is even possible for us to convert existing single glazed sashes to accept double glazed units.  Double glazing combined with our restoration and draught seal procedure provides an obvious overall improvement to the comfort of your home. 

All the work at Barnsbury Joinery Co. is designed to be as unobtrusive as possible, being machined into the timber components to become an "invisible" part of the window.  The appearance of the property is virtually unaltered, preserving the character and charm, yet offering you the increased comforts of modern alternatives.

Our Double Glazed Sash Replacement Includes: 

  • Survey of existing frames.

  • Our standard restoration & draught seal service.

  • Bespoke timber sashes.

  • Balancing the weighting mechanism, to ensure ease of operation.

  • Large selection of double glazed units.

  • A choice of paint finishes. 

  • A wide range of ironmongery in a choice of finishes.


Upgrading to Double Glazed Slimline Units: 

We can replace the double glazed unit in your sash and casement windows. Generally speaking a thickness of 18mm is considered to be about the maximum allowed before the unit starts to look different to a traditional sash and casement window. Exceeding this thickness of glass may often clash with local legislation and building controls. In listed buildings and conservation areas a slimline unit is usually required. Its thickness is usually around 14mm, 4/6/4, argon filled, low e glass unit. For no additional cost we will fit toughened glass to the lower sash for reasons of safety. We also provide Triple Glazing Windows at Barnsbury Joinery. 

To save time at Barnsbury Joinery we have implemented an online quote request system. Once we receive your request we will endeavor to contact you within 48 hours. If you require assistance or would like to discuss your requirements, please do not hesitate to contact us directly on 0207-1646306 and we will be happy to help you.


At Barnsbury Joinery Co we service all of London and Hertfordshire. Including Islington, Hackney, Hampstead, Primrose Hill, Camden, Stoke Newington, Clapham, Angel, Canonbury, De Beauvoir Town and Clerkenwell. Please call us now to find out if we work in your local area.



Barnsbury Joinery Co.

London Head Office 

Ripplevale Grove, 

Islington, London. 


Tel:   0207-1646305

Mob: 07399779872

Mob: 07913372092



Barnsbury Joinery Co.

Hertfordshire Head Office 

Blacksmiths Lane, 

St Albans. 


Tel:   0207-1646305

Mob: 07399779872

Mob: 07913372092

Barnsbury Joinery Co. © 2020 London's Leading Bespoke Joinery Company. All rights reserved.