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 Northolt, as anywhere in London, the price of replacement windows is driven mainly by size, materials and access. Across London our guide sits at £5,800–£11,500 with VAT, but restricted parking, a narrow side passage or extra preparation can move the figure either way. That is why every price we give follows a visit to the house.
- Guide price
- £5,800–£11,500 inc VAT
- Time on site
- 1–2 days on site for a typical house
- Postcodes
- HA2, HA4, UB1, UB4 and UB5
- Planning rules
- England
- Local area
- Greater London
- Survey
- Free, with a written quote
How much do replacement windows cost in Northolt?
Use the table to gauge the cost of replacement windows in Northolt before we visit. Figures include VAT and are scaled for London, coming out about 30% above the national guide, which gives £5,800–£11,500 overall. After a free survey, you receive a fixed written price.
| Type of job | What it usually involves | Guide in Northolt |
|---|---|---|
| One to three windows | Replacing a few problem windows, such as a bay or a rotten kitchen window, in uPVC. | £900–£3,900 |
| Whole house in uPVC | Eight to ten standard uPVC casement windows on a typical 3-bed semi, fitted and finished. | £5,800–£9,800 |
| Whole house in aluminium or flush sash | Premium frames, colours or period styles across a typical 3-bed home. | £9,800–£18,000 |
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
- Double-glazed units as standard, with triple glazing as an option
- 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
Building in Northolt
London's housing is dominated by Victorian and Edwardian terraces, often in yellow London stock brick, with Georgian terraces in central districts and mansion blocks across many inner areas. Outer boroughs have large belts of interwar semis, and there are extensive post-war council estates. Many houses have been split into flats, and conservation areas are widespread.
Terraces suit side-return extensions and rear dormer loft conversions; interwar semis commonly take hip-to-gable lofts. Shared party walls, restricted parking and conservation rules often shape the plans and the programme.
If your house in Northolt fits one of these patterns, it helps us anticipate what replacement windows will involve, though we always confirm the details on site.
Do you need permission in Northolt?
Each UK nation sets its own consent rules, and Northolt is in England. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
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.
From survey to handover
Free site survey
A free survey comes first. It gives us what we need to price replacement windows properly, including dimensions, existing materials and access for deliveries, and gives you the chance to ask anything you like.
Price and scope agreed
After the survey we send a quote for replacement windows that fixes the price for the scope we've agreed. If you want to change materials or scope, we revise it in writing before anything is booked.
Plan and prepare
Before anyone starts, we confirm the programme in writing, check whether consents are required and arrange deliveries. If a skip or scaffolding on the road needs a permit, we apply for it.
Build and hand over
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
How we work
Replacement windows in Northolt: questions
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.
Can you combine replacement windows with other work?
Yes. Because we manage several trades under one contract, we can plan replacement windows alongside other work on your Northolt home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
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.
Will new windows stop condensation?
New windows reduce condensation on the glass because the inner pane stays warmer, but they do not remove the moisture in the air that causes it. Modern frames are also more airtight, so ventilation matters more after replacement. We fit trickle vents where regulations require them, and we suggest using extractor fans and opening windows regularly. If walls are damp or mouldy, it is worth looking at ventilation and heating at the same time.
Which postcodes in Northolt do you cover?
We cover HA2, HA4, UB1 and UB4, along with the rest of London. 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.
Near Northolt
We survey and quote throughout Northolt's HA2, HA4, UB1 and UB4 postcodes and in surrounding places such as Greenford, Harrow and Southall. The process and pricing approach are identical in each of them.

