Replacement windows are new frames and sealed double- or triple-glazed units fitted into your existing openings after the old windows are taken out, improving warmth, security and noise reduction while meeting current building regulations.
In Hertfordshire, we price replacement windows against our guide for the East of England, £4,700–£9,400 including VAT, then adjust it once we have surveyed your home. We work across Watford, Hemel Hempstead, Stevenage and St Albans and the rest of the county or region. Planning and building control requirements follow the rules for England, and we look into your property's position before a written quote is sent.
- Guide price
- £4,700–£9,400 inc VAT
- Time on site
- 1–2 days on site for a typical house
- Planning rules
- England
- Price level
- About 5% above the national guide
- Towns listed
- 19
- Survey
- Free, with a written quote
Replacement windows prices in Hertfordshire
These are guide costs, not quotes. For replacement windows in Hertfordshire the range is £4,700–£9,400, VAT included, reflecting prices in the East of England that are about 5% above the national guide. Once we have visited for a free survey, you get a firm figure for the scope you approve.
| Type of job | What it usually involves | Guide in Hertfordshire |
|---|---|---|
| One to three windows | Replacing a few problem windows, such as a bay or a rotten kitchen window, in uPVC. | £750–£3,200 |
| Whole house in uPVC | Eight to ten standard uPVC casement windows on a typical 3-bed semi, fitted and finished. | £4,700–£7,900 |
| Whole house in aluminium or flush sash | Premium frames, colours or period styles across a typical 3-bed home. | £7,900–£14,500 |
Your price depends mostly on:
- Number and size of windows, including bays and large picture windows
- Frame material, colour and finish, inside and out
- Window style, such as sash, flush sash or tilt-and-turn
- Upper-floor access, scaffolding and the condition of reveals and sills
What do you get?
- Measured survey of every opening, with sizes checked before manufacture
- Made-to-measure frames in your chosen material, colour and style
- Careful removal and disposal of the old frames and glass
- Fixings, packers, foam and weather seals to suit your wall type
- New internal trims, external cills and neat sealant finishing
- Trickle vents, escape hinges and safety glass where regulations require
Housing across Hertfordshire
Hertfordshire is home to the first garden cities, Letchworth and Welwyn Garden City, and the post-war new towns of Stevenage, Hatfield and Hemel Hempstead. Watford and St Albans have Victorian terraces and Georgian streets, interwar semis line the commuter suburbs, and brick-and-flint cottages appear in Chiltern villages to the west.
New-town and garden-city homes often suit extensions, window replacement and roofline renewal, though some garden-city estates have their own design guidance. Victorian terraces commonly take loft rooms and side-return extensions.
Generally dry with chalk and clay soils; clay areas can move in long dry spells, and mature trees near houses need considering for foundations.
Do you need permission in Hertfordshire?
The notes below cover England, which is where Hertfordshire sits. Rules change and every property is different, so we speak to the council before pricing your job.
Replacing windows and doors on a house is usually permitted development in England when the new ones look broadly similar to the old. Flats, listed buildings and homes covered by an Article 4 direction can need consent, and conservation areas may limit materials or styles.
Replacement windows and external doors must meet Building Regulations for energy efficiency, ventilation and, on upper floors, escape. The work is either self-certified by an installer registered with a competent person scheme or signed off by building control.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
How does the job run?
We look at the job
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for replacement windows, and photograph or measure anything the quote needs to reflect.
Your fixed price
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Plan and prepare
We handle the paperwork side: checking whether planning permission or building control approval is needed, submitting applications where they are, and scheduling the trades and materials around your dates.
Finish and handover
During the work we protect the areas around it and tidy up at the end of each day. Once complete, we check the finish, remove our materials and hand over paperwork such as building control sign-off where it applies.
What you can expect from us
Frequently asked questions
How long does it take to fit windows in a house?
Fitting replacement windows in a typical 3-bed house usually takes one to two days on site. We take out and fit one window at a time, so each room is weathertight again within an hour or two. Bays, sash windows and homes needing scaffolding take longer. Manufacture comes first: made-to-measure frames typically take a few weeks to arrive after the survey and your order are confirmed.
How do I look after new uPVC or aluminium windows?
Caring for new windows is simple: wash frames and glass with warm soapy water a few times a year, avoiding abrasive cleaners and solvents. Clear the drainage slots at the bottom of the frame so rainwater can escape, and put a drop of light oil on hinges and locking points once a year. Check seals and the sealant around the outside every few years, and replace any that have cracked or shrunk.
Which postcodes in Hertfordshire do you cover?
We cover WD1, HP1, SG1 and AL1, along with the rest of Hertfordshire. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
Do I need planning permission in Hertfordshire?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Hertfordshire is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
What happens on the day the windows are fitted?
On fitting day we lay dust sheets, protect floors and furniture near each window, and then remove the old frame carefully to limit damage to plaster. The new frame is fixed, packed, sealed and glazed, and internal trims and external cills are finished. We take away the old windows and clean the glass before leaving. You only need to clear sills and take down curtains and blinds.
Towns in Hertfordshire
Homes in all of the following Hertfordshire towns can get a written quote for replacement windows. Open a town page to see prices and the postcodes we cover.