.avif)
If your double glazed sash windows have issues such as condensation between the panes, damaged frames, or faulty mechanisms, our skilled craftsmen can repair them, ensuring they regain their insulating properties and visual appeal. Common problems we fix include:
Misted or failed double glazing – We can replace individual glazed units without the need for a full window replacement.
Rotting or damaged timber frames – Our expert joiners repair or replace decayed sections while maintaining the integrity of the original design.
Faulty sash cords, balances, or pulleys – We restore smooth and effortless window operation.
Draughts and leaks – We provide draught proofing solutions to prevent heat loss and improve energy efficiency.
Broken or loose glazing bars – Ensuring the traditional character of your windows remains intact.
Free Aftercare Visit: Your satisfaction is our priority, which is why we offer a complimentary aftercare visit within 12 months of the installation. We’ll check that everything is functioning perfectly and address any issues that may have arisen completely free of charge.
If your existing double glazed sash windows are beyond repair, we offer custom-built replacements that match the original style of your property while integrating the latest advancements in glazing technology.
Our replacement windows feature:
High performance double glazing for superior insulation and reduced energy bills.
Bespoke timber frames crafted from premium materials such as Accoya wood, ensuring longevity and durability.
Traditional aesthetics with modern efficiency, maintaining your home’s period charm while improving its thermal performance.
Customisable glazing options, including low-emissivity glass, acoustic glass, and toughened safety glass.
Heritage-approved designs, meeting conservation area requirements while upgrading your home’s comfort and security.
We carefully match your existing windows' style and proportions to ensure that any new installation seamlessly blends with the character of your home.
At Traditional Sash Windows and Carpentry, we use only premium materials to ensure durability, insulation, and aesthetic appeal. Our materials include:
Hardwood – A stable and strong option for maintaining a traditional look.
Accoya wood – A sustainable, highly durable timber that resists rot and provides exceptional longevity.
High-performance double glazing – We use low-emissivity (Low-E) glass for enhanced thermal efficiency.
Weather-resistant finishes – Our timber is treated with high-quality microporous paints and stains to ensure long-lasting protection.
Heritage ironmongery – Traditional fittings such as brass, nickel, and wrought iron hardware maintain the authentic look of period properties.
The concept of double glazing dates back to the 19th century, although it was not widely adopted until the middle of the 20th century, when energy efficiency became an increasing concern. Traditional single-glazed sash windows, commonly found in period properties, often allowed significant heat loss and could be affected by cold draughts.
The development of double glazing for sash windows gave homeowners the opportunity to retain the character and visual appeal of their original windows while benefiting from improved thermal insulation, reduced draughts and better noise reduction.
Today, advances in glazing technology, timber treatments, manufacturing methods and draught-proofing systems allow double-glazed sash windows to provide excellent energy efficiency and lasting performance while preserving the historic appearance and architectural character of period properties.
Early innovation - Basic forms of double glazing were used in parts of Scotland during the 19th century to provide greater protection against severe winter weather.
Suitable for heritage properties – Many listed buildings now allow double glazed sash windows if they match the original aesthetic.
Improved energy efficiency – High-quality double glazing can significantly reduce heat loss compared with single glazing, helping to create a warmer home and lower energy consumption.
Acoustic benefits – Secondary glazing, acoustic glass and carefully specified double-glazed units can reduce external noise, making them particularly useful for homes in busy areas.
Custom glass options – Modern double glazing is available with decorative, obscured, laminated, acoustic and solar-control glass, allowing it to meet a wide variety of practical and aesthetic requirements.
Skilled craftsmanship – With extensive experience in traditional joinery and sash window restoration, our team delivers careful workmanship and consistently high-quality results.
Improved energy efficiency – Our repairs and replacements can help reduce heat loss, limit cold draughts, lower energy consumption and create a more comfortable indoor environment.
Heritage-sensitive approach – We respect the proportions, details and architectural character of period properties while introducing appropriate improvements in thermal and acoustic performance.
Bespoke solutions – Every repair or replacement is carefully planned around the condition of your existing windows, the style of your property and your individual requirements.
Quality materials – We use durable timber, high-performance glazing and compatible components selected to provide reliable operation, attractive results and lasting performance.
Investing in double-glazed sash window repairs or replacements is an effective way to improve the comfort, energy efficiency, appearance and value of your home. Whether you want to preserve the character of a period property, reduce heat loss, limit cold draughts, improve sound insulation or increase security, our experienced team at Traditional Sash Windows and Carpentry will ensure that every stage of your project is completed with care and attention to detail.
Our approach combines traditional joinery skills with modern glazing technology and high-quality materials. Wherever possible, we retain and repair original timber to preserve the architectural character of your windows. When replacement is required, we manufacture bespoke sash windows that complement the proportions and detailing of your property while delivering improved thermal performance, smooth operation and lasting durability.
With our commitment to skilled craftsmanship, responsible repair and carefully selected materials, we help homeowners continue to enjoy the timeless appearance of traditional sash windows while benefiting from modern levels of comfort and performance.
If you are considering repairing, upgrading or replacing your sash windows, contact us today to arrange a consultation. Our knowledgeable team can assess your existing windows, explain the available options and recommend a solution suited to your property, priorities and budget.
Last updated 2026-09-17
Yes. Traditional timber sash windows can often be upgraded with double-glazed units while retaining their original style and proportions. Depending on the condition and depth of the existing sashes, we may be able to reglaze them or manufacture new replacement sashes designed specifically for double glazing.
In some cases, yes. This depends on the condition, thickness and design of the existing sashes. Older or particularly slim sashes may not have enough timber to safely accommodate double-glazed units. Following an inspection, we can advise whether reglazing is suitable or whether replacement sashes would provide a better long-term result.
We take care to preserve the traditional appearance of the windows wherever possible. New sashes can be manufactured to replicate the original glazing bar layout, mouldings, horns and other period details. Slimmer double-glazed units may also be available where maintaining narrow sightlines is important.
Double glazing can help reduce heat loss, improve comfort, reduce outside noise and minimise cold draughts around the glass. When combined with professional draught proofing, it can significantly improve the overall performance of traditional sash windows.
Double glazing can reduce condensation on the inside surface of the glass because the internal pane normally remains warmer than single glazing. However, condensation can also be caused by high humidity, limited ventilation or cold areas elsewhere in the room, so double glazing may not eliminate it completely.
Double glazing can help reduce outside noise, although the level of improvement depends on the glass specification, the gap between the panes and the condition of the window. Acoustic laminated glass, secondary glazing and effective draught proofing may provide better results where noise reduction is the main priority.
Alterations to listed buildings usually require listed building consent, and properties in conservation areas may also be subject to planning restrictions. We can manufacture windows and sashes that closely replicate the existing design, but the property owner should confirm any consent requirements with the local planning authority before work begins.
The glass specification will depend on the size, design and location of the window. Options may include standard energy-efficient double glazing, toughened safety glass, laminated glass, acoustic glass, patterned glass and vacuum glazing. We will recommend a suitable specification as part of the quotation.
Slimline double glazing uses a narrower overall unit than standard modern double glazing. It is designed for traditional windows where glazing rebates and sightlines are more restricted. Availability and suitability depend on the window design, required performance and manufacturer’s limitations.
Vacuum glazing uses two panes of glass separated by an extremely narrow vacuum space. It can provide strong thermal performance while remaining much thinner than conventional double glazing. This makes it particularly useful for traditional sash windows where preserving slim glazing details is important.
Yes. If the sealed unit has failed and moisture has entered between the panes, we can normally replace the glass without replacing the complete window. We will also inspect the surrounding putty, glazing beads and timber for any additional repairs that may be required.
Yes. Where required, we can repair rotten or damaged timber using specialist resin systems, timber splicing or replacement components. If the sash is beyond economical repair, we can manufacture a new replacement sash to match the original window.
Yes. Double glazing can be combined with an overhaul and draught-proofing service. This may include easing and adjusting the sashes, replacing sash cords or spiral balances, servicing the pulleys and weights, installing draught-proofing seals and fitting suitable new ironmongery.
Yes. Double-glazed sashes are usually heavier than single-glazed sashes, so the sash weights or spiral balances may need to be adjusted or replaced. We calculate the correct balancing system to ensure the windows remain safe and easy to operate.
Yes. Double-glazed sashes are usually heavier than single-glazed sashes, so the sash weights or spiral balances may need to be adjusted or replaced. We calculate the correct balancing system to ensure the windows remain safe and easy to operate.Yes. We manufacture complete replacement timber sash windows and box frames using durable hardwoods and modified timbers such as Accoya. New windows can be made to replicate existing period details while incorporating modern double glazing, draught proofing and security hardware.
Yes. Double-glazed sashes are usually heavier than single-glazed sashes, so the sash weights or spiral balances may need to be adjusted or replaced. We calculate the correct balancing system to ensure the windows remain safe and easy to operate.