Dorset · England
Sash Windows in Dorset
Homeowners and landlords in Dorset can get a written sash window quote that fixes the price for the joinery, glass, colour and hardware shown.
- Guide from £1,495
- 7 towns covered
- Postcode areas BH, DT, SP
Replacement sash windows for homes and businesses in Dorset
In England, Approved Document L allows an alternative where a window must keep a building's character: a centre-pane U-value no worse than 1.2 W/m²K, or single glazing supplemented by low-E secondary glazing. Otherwise a replacement should meet 1.4 W/m²K or Window Energy Rating band B.
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.
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.
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.
Towns we cover for sash windows in Dorset
Choose your town for local details, nearby areas and the postcode districts we cover.
What applies in Dorset
Approved Document K requires safety glass in critical locations in England: glazing in doors and in side panels within 300 mm of a door, up to 1500 mm above floor level, and any glazing in walls or partitions up to 800 mm above floor level.
In England, replacing a whole window, roof window or glazed external door is building work. It has to be notified to building control, either by an installer registered with a competent person scheme such as FENSA or Certass, or through a building notice to the council. Replacing only the glass in an existing frame is a repair and is not notifiable.
Dorset 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.
Terraced streets and conservation areas often control sash details on front elevations, so check requirements before ordering. Flats need planning permission and freeholder consent, and upper-floor sashes are usually fitted from inside, with careful protection of communal stairs and hallways.
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
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.
Heritage glass options
Slim double glazing, low-E coatings and textured glass that looks like old cylinder glass for sensitive elevations.
Sash Windows in Dorset: questions
How much do sash windows cost?
The cost of sash windows depends on size, material, whether you replace the whole frame or only the sashes, the glazing bar pattern, the glass and the finishing details such as horns and mouldings. Timber usually costs more than uPVC, and listed building work costs more again. See the guide prices for typical ranges; the written quote fixes your price.
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.
Do sash windows have to meet building regulations?
Yes. Replacement windows are controlled under building regulations across the UK, and the detail differs between nations. In England, the work can be self-certified by an installer registered with a competent person scheme or approved by building control. Energy, ventilation, safety glazing and escape all apply, though listed buildings may meet some standards only where reasonably practicable.
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.
Which parts of Dorset do you cover for sash windows?
We cover the whole of Dorset, including Bournemouth, Poole, Weymouth, Christchurch and Dorchester, and postcode areas BH, DT, SP. Building rules for sash windows here follow the regulations for England. 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 Dorset
- Replacement Glass in Dorset
- Misted Glass Repair in Dorset
- Emergency Glazing in Dorset
- Safety Glass in Dorset
- Window Repairs in Dorset
- Window Film in Dorset
- uPVC Windows in Dorset
- Aluminium Windows in Dorset
- Composite Doors in Dorset
- Bifold Doors in Dorset
- Sliding Doors in Dorset
- Secondary Glazing in Dorset
- Roof Lanterns in Dorset
- Glass Balustrades in Dorset
- Frameless Glass in Dorset
- Shower Screens in Dorset
- Glass Splashbacks in Dorset
- Bespoke Mirrors in Dorset
- Glass Roofs in Dorset
- Shopfront Glazing in Dorset
- Curtain Walling in Dorset
- Glass Partitions in Dorset
- Property Glazing in Dorset
Get a written quote in Dorset
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.