How much do sash windows cost in North London? In 2026, bespoke timber sash windows in North London range from £1,200 to £2,800 per window supplied and fitted. This complete price guide breaks down what affects the cost, what’s included in our quotes, and how to budget for full house re-fenestration in Hampstead, Highgate, Islington, Camden and across the rest of North London.

At International Windows Group we manufacture and install bespoke timber sash windows from our own workshop, with transparent pricing and no hidden extras. Free survey, written quotation within 5 working days, 4 weeks lead time after deposit.

Sash Windows Cost in North London — 2026 Summary

Below is a quick reference table showing typical cost ranges for sash windows in North London. All prices include manufacture, glazing, ironmongery, finish and full installation. VAT applies to most installations (some Listed Building work qualifies for reduced VAT).

• Small box sash window (600 × 1200mm) — £1,200 to £1,500
• Standard Victorian sash window (900 × 1500mm) — £1,500 to £1,900
• Large Georgian sash window (1100 × 1800mm) — £1,900 to £2,400
• Bay window (3 sashes combined) — £3,500 to £5,500
• Full house re-fenestration (6-8 windows, Victorian terrace) — £10,000 to £18,000
• Full house re-fenestration (10-14 windows, Georgian townhouse) — £18,000 to £35,000

These ranges reflect our complete service: workshop manufacture, double glazing, ironmongery, factory finish, removal of old windows, professional installation, making good of reveals, and aftercare guarantee. For a precise quote based on your property, use our sash windows cost calculator or request a free survey.

What Affects the Cost of Sash Windows in North London?

Size and Configuration

The single biggest cost factor is window size. A small bathroom sash window is typically half the price of a tall Georgian drawing room sash. The number of individual panes also matters — windows divided into multiple smaller panes by glazing bars require more labour to manufacture and glaze than single-pane sashes. Most North London Victorian properties have 6-over-6 or 2-over-2 configurations; Georgian townhouses often have 6-over-6 or 8-over-8.

Timber Species

Timber choice significantly affects both price and service life:

• European Redwood — most affordable option, 25-35 year service life with proper maintenance. Suitable for budget-conscious projects.
• Engineered Hardwood (Sapele, Meranti) — mid-range pricing, 40-50 year service life, excellent stability. Our most popular choice for North London Victorian properties.
• Accoya — premium modified softwood with 50+ year service life and 50-year manufacturer warranty. Best long-term value despite higher upfront cost. Recommended for Listed Buildings and exposed positions.

Read more about our bespoke timber windows guide for detailed timber comparisons.

Glazing Specification

Modern slim-profile double glazing (14-16mm units) is standard for new sash windows in 2026. Upgrading to triple glazing adds approximately 15-20% to the glazing cost but significantly improves thermal performance and acoustic insulation. For properties on busy North London roads, acoustic glazing is often the most cost-effective upgrade.

For a detailed comparison of glazing options, see our guide to double vs triple glazing in London.

Conservation Area Requirements

Properties in Hampstead, Highgate, Primrose Hill, Bedford Park, Crouch End, Stoke Newington and other North London conservation areas typically require period-authentic specifications: hand-finished putty lines, traditional mouldings, matched paint colours, and authentic glazing bar profiles. These details add approximately 10-15% to the base cost but are usually mandatory for planning approval.

Read our guide to Victorian sash windows restoration, replacement and conservation for more on heritage requirements.

Installation Complexity

Some properties cost more to install:

• Bay windows requiring careful disassembly and structural support
• Properties with internal shutters that need preserving
• Listed Buildings where Heritage Officers require specific working methods
• Upper floors requiring scaffolding access
• Fragile surrounding plasterwork or cornicing that needs protection

Standard ground and first floor installations in Victorian terraces don’t typically require scaffolding and fall in our base price range.

Cost Breakdown by Sash Window Type

Box Sash Windows

Traditional weighted box sash windows are the most authentic option for Victorian and Georgian North London properties. The internal box construction houses cast-iron weights connected by sash cords, providing smooth counterbalanced operation.

Typical cost in North London: £1,400 to £2,400 per window supplied and fitted, depending on size and timber species. Listed Building specifications with hand-finished putty lines and period mouldings sit at the upper end of this range.

Browse our complete timber sash windows range for technical details.

Spring Balance Sash Windows

Modern engineered alternative using concealed spring mechanisms instead of weights. Identical appearance from outside but with slimmer frames and easier installation. Suitable for properties outside Conservation Areas.

Typical cost in North London: £1,200 to £2,000 per window supplied and fitted. Generally 10-15% cheaper than equivalent box sash because of simpler construction.

Double Glazed Timber Sash Windows

Standard specification for most new sash window installations in 2026. Slim 14-16mm double glazed units with argon filling and low-E coating deliver U-values from 1.4 W/m²K — close to modern Building Regulations standards while maintaining period appearance.

Typical cost in North London: Included in standard pricing above. No additional cost over single glazing for new installations.

uPVC Sash Windows

For properties outside Conservation Areas where lower maintenance is the priority, uPVC sash windows are typically 30-40% cheaper than timber.

Typical cost in North London: £700 to £1,400 per window supplied and fitted. Note that uPVC is not normally approved for Listed Buildings or Conservation Areas.

Sash Window Restoration & Repair

Where original sashes are structurally sound, restoration is often more cost-effective than full replacement and preferred by Heritage Officers for Listed Buildings.

Typical cost in North London: £400 to £900 per window for full restoration including draught-proofing, weight re-cording, refurbishment, new glazing and repainting.

What’s Included in Our Sash Window Quotes

Every quote from International Windows Group includes:

• Workshop manufacture in your chosen timber species
• Double glazed sealed units (or triple glazed if specified)
• Period-correct mouldings, horns and glazing bars
• Traditional ironmongery (sash lifts, sash locks, brass cords)
• Factory paint finish in your chosen colour
• Removal and disposal of existing windows
• Full installation by our in-house teams
• Making good of internal and external reveals
• Site cleaning and rubbish removal
• 10-year manufacturer warranty on frames
• 5-year warranty on installation workmanship
• 10-year warranty on glazing units

No hidden extras. No surprise charges after the survey. Browse our certificates page for compliance documentation.

Sash Window Cost by North London Area

Costs in our quotes vary slightly by area depending on access, parking restrictions, and typical property style:

• Hampstead (NW3) — Premium properties, Conservation Area requirements, parking permits often needed. Average quote: £14,000-£28,000 for full re-fenestration.
• Highgate (N6) — Listed Buildings common, period-authentic specifications. Average quote: £15,000-£32,000.
• Islington (N1) — Georgian townhouses with tall windows, 8-12 windows typical. Average quote: £16,000-£28,000.
• Camden (NW1) — Mix of Victorian and Georgian, varied requirements. Average quote: £12,000-£25,000.
• Muswell Hill (N10) — Edwardian semis with 8-10 windows typical. Average quote: £12,000-£22,000.
• Crouch End (N8) — Victorian terraces with 6-8 windows. Average quote: £10,000-£18,000.
• Barnet, Finchley (N3, N12, N20) — Suburban properties, easier access. Average quote: £9,000-£20,000.
• Stoke Newington (N16) — Conservation areas, Victorian terraces. Average quote: £11,000-£20,000.

For complete coverage details, see our sash windows North London page.

How to Reduce the Cost of Sash Windows in North London

If budget is a constraint, here are realistic ways to reduce the total cost without compromising on quality:

• Phase the project — replace the worst windows first (typically front-of-house), then upgrade the rest over 1-2 years.
• Choose European Redwood — saves approximately 15-20% versus Accoya, still delivers 25-35 year service life with proper maintenance.
• Consider spring balance sashes — 10-15% cheaper than weighted box sash, identical appearance from outside.
• Combine orders with neighbours — if your neighbours need windows too, combined orders can attract discount on installation logistics.
• Restoration before replacement — if existing sashes are structurally sound, restoration costs 50-70% less than full replacement.
• Skip triple glazing unless needed — double glazing meets most thermal and acoustic requirements; triple glazing is only cost-effective for very noisy locations or exposed positions.

How Long Does the Quote Process Take?

Our complete quote process is designed to be straightforward and transparent:

1. Initial enquiry — call, email or use our contact form. We respond within 24 hours.
2. Free survey — typically arranged within 5-7 working days at a time that suits you. The survey takes 60-90 minutes.
3. Written quotation — delivered within 5 working days of the survey, with each window itemised separately.
4. Specification review — we discuss any changes you’d like to make, with revised quote within 2-3 days.
5. Order confirmation — deposit secures your place in our producti