Home » Sash Window Services UK & AU » Commercial Window Restoration

Commercial Window Restoration

Commercial Sash Window Company

Period window & door contractors for builders & architects.  Public, private, government & commercial period buildings.  Hotels, pubs, churches & schools.


Extensive repair service for heritage timber windows

Our repair service ensures that as much of the remaining heritage frame is retained as is practical. Rotten timber is cut away and repaired with a timber splice and or marine grade epoxy resins.

Glazing & putty services

Traditional timber sash glazing methods.Replacement glass with traditional linseed putty in a timber sash.

Replacement glazing and traditional linseed putty pointing.

Safe stripping of lead based paints.

Stripping of old paint coverings in a compliant manner

lead based paint removal from old windows.

paint stripping timber sash windows.


Routine & scheduled maintenance.

replace broken cords in a timber sash.replace broken glass in timber sash window.

As well as larger projects we also attend to those smaller jobs such as broken cords or smashed glass.

Sealing draughts in public and commercial heritage buildings will return significant savings in heating and cooling costs, as up to 25% of energy is lost via air leakage.


Comfort Hush modern glass in a replica timber sash frame.Weather seals in a timber sash window stop rattles, noise and cold.

Improving energy efficiency & reducing noise from period windows.

Our draught sealing service is the best and least intrusive way of achieving improved performance from old windows. The seals are machined into the timber components to become an integral, practically invisible part of the window. 

Traditional double-hung sash windows are not regarded as being very energy efficient or quiet.  The sliding sash window frames have inherent gaps that allow the sashes to slide and the timber frames can also warp over time, creating larger gaps where air leakage and air infiltration originate. 

Draught-stripping existing period sash windows can reduce the draughts from them by almost 90%, therefore significantly reducing the air cooling or heating requirement needed for the room.  Warm or cold draughts make air cooling and heating systems work harder and make occupants feel uncomfortable, often adjusting room thermostats to compensate.  

Sash Window Repair & Draft Seal at Katanning Mill Restoration WA

Glazing upgrades with modern high performance glass can insulate us from the heat and cold, keep our offices quieter and protect us from intruders.  Specialist window films such as anti-graffiti or explosion protection are also avaliable.

Heat also passes through the glass itself but less than a quarter of the heat transfer through a typical sash window is by conduction, the rest is by air infiltration - draughts.   Heavy curtains or close-fitting roller blinds can help cut the amount of heat transfer through glass by more than 30%. 

"Draught-proofing is one of the most cost effective and least intrusive ways of improving the comfort of occupants and reducing energy used for heating with little or no change to a building’s appearance." Historic England


At Sash Window Specialist we understand the charm of traditional wooden windows which is why all of our work is designed to be as sympathetic as possible.

Public building window renovation | Parliament House Western Australia

'Authentic Replica' bespoke joinery

Authentic Replica Timber Sash Windows. Douglas Fir. Replica Timber Sash Windows. Fiji Mahogany.
Our Authentic Replica replacement joinery is hand crafted from a range of timbers including Jarrah and Oregon (Douglas Fir). We copy all existing dimensions and fine detail such as horn patterns and glazing bar mouldings ensuring a top quality product compliant with all Heritage Conservation Codes.

Our draught seals are machined into the timber components to become an integral, practically invisible part of the window. Our Draught Seal & Restore Service is ideal for conservation areas and listed buildings.

Heritage aproved draught seals

We have been using the same top quality British made draught seals for over 20 years.  Brush draught seals are the best option for long life in a sliding sash window.

Commercial projects are priced differently to the residential contracts we undertake.  Restoration projects in public and commercial heritage buildings present unique environments that are priced on a case by case basis.