Gwynedd & Anglesey · Wales
Sash Windows in Gwynedd & Anglesey
Homeowners and landlords in Gwynedd & Anglesey can get a written sash window quote that fixes the price for the joinery, glass, colour and hardware shown.
- Guide from £1,495
- 5 towns covered
- Postcode areas LL
Replacement sash windows for homes and businesses in Gwynedd & Anglesey
Heavy double glazed sashes need matching weights. When single glazed sashes are swapped for double glazed ones in an existing box, the old weights are usually too light, so the glazier re-weighs each sash to stop it dropping or creeping up, and checks the pulleys can carry the load.
Sash window prices depend on size, timber or uPVC, whether you replace the whole frame or just the sashes, the glazing bar pattern, horns and mouldings, glass type and the paint colour. Listed or conservation work that needs matching details costs more. See the guide prices for typical ranges.
A traditional box sash hides cast-iron or lead weights inside the side boxes of the frame, connected to each sash by cords running over pulleys. Modern sash windows often use spiral or spring balances instead, which take up less depth and suit uPVC and some new timber designs without weight pockets.
Security on sash windows comes from keyed sash locks at the meeting rails, sash stops that limit the opening for ventilation and child safety, laminated glass, and close-fitting staff and parting beads. Ground-floor sashes in older houses are often the weakest point, so locks are worth upgrading during replacement.

Towns we cover for sash windows in Gwynedd & Anglesey
Choose your town for local details, nearby areas and the postcode districts we cover.
What applies in Gwynedd & Anglesey
In Wales, Approved Document N covers safety glazing: safety glass is needed in and around doors and in low-level glazing where people could walk into it.
Security rules for doors and windows differ between the UK nations. For replacement doors and windows in Wales, products tested to PAS 24 are a sensible benchmark.
Gwynedd & Anglesey has its own coastline, so for homes and businesses near the sea, salt air and wind-driven rain are part of the brief. Salt-laden wind and driving rain shorten the life of paint on exposed sashes, so coastal timber windows benefit from durable timbers, good factory coatings and regular inspection. Brass or stainless sash furniture resists corrosion better than plated steel near the sea.
Older rural houses often have sash openings that are out of square, with soft stone or lime plaster around them, so each window is measured individually and fitted gently. Exposed sites benefit from draught seals and robust weatherboards on the bottom sash.
Guide prices
| Typical job | Guide price inc VAT |
|---|---|
| uPVC sliding sash, 900 × 1500 mm | £1,495 – £1,995 |
| Timber-effect uPVC sash, 900 × 1500 mm | £1,795 – £2,295 |
| Painted timber sash, 900 × 1500 mm | £2,595 – £3,295 |
Choosing your sash windows
Heritage glass options
Slim double glazing, low-E coatings and textured glass that looks like old cylinder glass for sensitive elevations.
uPVC sliding sash
Low-maintenance uPVC frames with sculpted profiles and optional woodgrain foils, suited to homes where planning rules allow uPVC.
Glazing bar patterns
Two over two, six over six or other bar layouts, as true divisions or bars bonded to the glass faces.
Spring-balanced timber sash
Timber sashes running on concealed spring balances, giving a slimmer frame where weight pockets are not needed or space is tight.
Sash Windows in Gwynedd & Anglesey: questions
What guarantee comes with new sash windows?
Manufacturer guarantees apply to the joinery, finish, sealed units and hardware, and the terms are confirmed in writing. Cover on the paint finish often depends on regular maintenance, so check the conditions. Guarantee terms for the installation are set out in writing with your quote, so you know what is covered before agreeing to go ahead.
Will double glazed sashes be too heavy for my existing frame?
Double glazed sashes are heavier than single glazed ones, so the box frame, pulleys and weights must cope. When new sashes go into an existing box, the glazier checks the pulleys and adds or replaces weights so each sash balances. If the box is weak or rotten, a new frame is the better option, and the survey will tell you.
Should I repair or replace my sash windows?
Repair suits sashes where the timber is mostly sound and only cords, beads or small sections need attention, especially in listed or conservation properties. Replacement suits frames with widespread rot, distortion or repeated failures, or where you want double glazing and better security. A survey of each window shows which approach makes sense, and we can quote either.
Can I have double glazed sash windows in a listed building?
Sometimes, but listed building consent is needed for significant works, and some councils will only accept repair of the original windows or slim double glazing with matching details. Secondary glazing is often accepted where new windows are not. Speak to your council's conservation officer before ordering; we can provide drawings and specifications to support an application.
Which parts of Gwynedd & Anglesey do you cover for sash windows?
We cover the whole of Gwynedd & Anglesey, including Bangor (Gwynedd), Holyhead, Caernarfon, Pwllheli and Dolgellau, and postcode areas LL. Building rules for sash windows here follow the regulations for Wales. Enter your postcode on the quote form and we will confirm cover; then a glazier will arrange a free survey before giving you a written quote.
Other glazing services in Gwynedd & Anglesey
- Replacement Glass in Gwynedd & Anglesey
- Misted Glass Repair in Gwynedd & Anglesey
- Emergency Glazing in Gwynedd & Anglesey
- Safety Glass in Gwynedd & Anglesey
- Window Repairs in Gwynedd & Anglesey
- Window Film in Gwynedd & Anglesey
- uPVC Windows in Gwynedd & Anglesey
- Aluminium Windows in Gwynedd & Anglesey
- Composite Doors in Gwynedd & Anglesey
- Bifold Doors in Gwynedd & Anglesey
- Sliding Doors in Gwynedd & Anglesey
- Secondary Glazing in Gwynedd & Anglesey
- Roof Lanterns in Gwynedd & Anglesey
- Glass Balustrades in Gwynedd & Anglesey
- Frameless Glass in Gwynedd & Anglesey
- Shower Screens in Gwynedd & Anglesey
- Glass Splashbacks in Gwynedd & Anglesey
- Bespoke Mirrors in Gwynedd & Anglesey
- Glass Roofs in Gwynedd & Anglesey
- Shopfront Glazing in Gwynedd & Anglesey
- Curtain Walling in Gwynedd & Anglesey
- Glass Partitions in Gwynedd & Anglesey
- Property Glazing in Gwynedd & Anglesey
All glazing in Gwynedd & Anglesey · Sash Windows across the UK
Get a written quote in Gwynedd & Anglesey
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.