House extensions including rear, side-return, wraparound, and double-storey projects. Budget realistically with a published range from £45,000 to £320,000, backed by clearer scope notes, delivery context, and direct office guidance before you commit.
Transparent scope
Every quote is broken down clearly so you can compare tiers, finishes, and allowances without guesswork.
Local delivery context
We price around Crouch End Broadway access, property type, and programme constraints rather than using a generic London average.
Office-first support
You can speak to the office for budgeting, specification, and scheduling before booking a site visit.
Use these ranges to shortlist the right level of specification, then speak to the office for a more precise scope review based on your property, access, and finish standard.
Budget band
Side-return or compact rear extension
Typical budget
£45,000 - £80,000
Best when you want side-return or compact rear extension without losing control of scope.
Most requested range
Single-storey rear extension with premium glazing
Typical budget
£80,000 - £160,000
Best when you want single-storey rear extension with premium glazing without losing control of scope.
Budget band
Complex extension with high-specification fit-out
Typical budget
£160,000 - £320,000
Best when you want complex extension with high-specification fit-out without losing control of scope.
Cost drivers
The published range is shaped by specification, property condition, and how much preparatory or structural work is needed before finishes can start.
Price signal
£45,000 to £320,000
This spread reflects entry, mid, and premium delivery tiers rather than an artificially compressed headline figure.
This is one of the first items we review when turning a broad guide price into a fixed quotation for your property.
This is one of the first items we review when turning a broad guide price into a fixed quotation for your property.
This is one of the first items we review when turning a broad guide price into a fixed quotation for your property.
This is one of the first items we review when turning a broad guide price into a fixed quotation for your property.
This is one of the first items we review when turning a broad guide price into a fixed quotation for your property.
Included in the quote
Typical programme
10-28 weeks
Final sequencing is confirmed once the survey and scope are agreed.
Warranty cover
10 year structural warranty where applicable
Installation and structural protections are set out clearly in your quote pack.
Quoted with
Labour, materials, management
Our published ranges are designed to reflect real delivery, not stripped-back headline numbers.
Local next step
Need the area view before deciding?
Review the main Crouch End Broadway hub to compare services, nearby coverage, and broader renovation context before requesting a fixed price.
View Crouch End Broadway coverage pageInteractive estimator
Drag the slider to set your floor area and pick a specification tier. The estimate updates live using Crouch End Broadway-specific pricing data.
Specification tier
Designer fixtures, bespoke joinery, premium worktops, smart-home pre-wire.
£1,000 / sqm at premium tier
Estimated total
£80,000
Likely range: £72,000 – £92,000
This estimate is a starting point. Final pricing depends on property condition, specification choices, and access constraints. We provide a fixed-price written quote after a free site survey.
Room-by-room
Every house extensions project breaks down into rooms with different scopes, costs, and durations. Below is the typical specification we deliver across Crouch End Broadway properties.
Bespoke or premium-fit kitchen in Crouch End Broadway including units, worktops, integrated appliances, lighting, plumbing, electrical, and finishes coordinated as a single trade package.
Typical cost
£12,000 – £45,000
Duration
3 – 5 weeks
Family bathrooms, en-suites, and cloakrooms designed for Crouch End Broadway property layouts. Stone, mosaic, large-format, or wet-room solutions.
Typical cost
£8,000 – £28,000 per room
Duration
2 – 4 weeks per room
Open-plan reception, dining, and family spaces. Where structure permits we open through party walls with steel beams to maximise light and flow in Crouch End Broadway period properties.
Typical cost
£10,000 – £35,000
Duration
4 – 6 weeks
Master suites, family bedrooms, and study/guest rooms. Built-in storage, lighting, smart-home pre-wire, and acoustic treatments where appropriate for Crouch End Broadway living patterns.
Typical cost
£4,500 – £18,000 per room
Duration
2 – 3 weeks per room
Entrance halls, landings, and stairwells — often the first impression in Crouch End Broadway period homes. We restore or replace balustrades, treads, doors, and floors as a coherent design statement.
Typical cost
£3,500 – £14,000
Duration
2 – 3 weeks
Boiler, hot-water cylinder, consumer unit, MVHR, electrical and plumbing infrastructure replaced or upgraded across the property. Often the hidden backbone of a house extensions project in Crouch End Broadway.
Typical cost
£8,000 – £25,000
Duration
2 – 4 weeks (concurrent with other trades)
Decision framework
The biggest single decision on a house extensions project is whether to refurbish the existing property or demolish and rebuild. Here's how we frame the trade-offs for Crouch End Broadway owners.
Refurbish
Most Crouch End Broadway period homes have sound brick, timber, and roof structures that are worth retaining. Refurbishment preserves character and avoids planning risk.
Rebuild
If the existing structure has serious subsidence, fire damage, or non-compliant additions, demolition and rebuild may be the cleaner route.
Our recommendation
Refurbish unless a structural engineer flags major issues at survey.
Refurbish
Conservation areas in Crouch End Broadway typically restrict demolition. Refurbishment, with permitted-development additions, is usually faster to consent.
Rebuild
New-build replacement requires full planning consent and often an environmental impact assessment. Listed buildings rule out rebuild entirely.
Our recommendation
Refurbish for almost all conservation-area and listed properties.
Refurbish
Refurbishment costs typically £1,200 – £2,500 per sqm for premium spec, with shorter programmes and lower professional fees.
Rebuild
New-build costs £3,000 – £5,000+ per sqm in prime London, plus 18-30 months of design, planning, and demolition costs.
Our recommendation
Refurbish for £1m – £3m budgets; rebuild only justified above £3m on the right plot.
Refurbish
Internal wall insulation, MVHR, and slim-double-glazed sashes can lift period homes to EPC C/B without altering external appearance.
Rebuild
New-build can hit EPC A and Passivhaus standards with mechanical ventilation, triple glazing, and air-tight detailing.
Our recommendation
Refurbishment usually closes the comfort gap at lower cost in period properties.
Refurbish
Refurbished Crouch End Broadway period homes command a premium for character. Buyers in this market value original features.
Rebuild
New-build replacements in period streets can struggle to match comparable refurbished sale values.
Our recommendation
Refurbish if your property has period character. Rebuild only on plots without heritage value.
How we sequence the build
An 18-week house extensions project breaks into 8 phases, each with specific trades, deliverables, and risks. Understanding the sequence helps you anticipate questions, decisions, and on-site moments.
Trades on site
Deliverables
Risk note
Hidden defects (damp, asbestos, non-compliant additions) are usually discovered here — budget a 10% contingency.
Trades on site
Deliverables
Risk note
Strip-out always reveals more than the survey predicted. Quick decision-making protects programme.
Trades on site
Deliverables
Risk note
Steel fabrication lead times can run 4-6 weeks — order early to avoid programme delay.
Trades on site
Deliverables
Risk note
First-fix sequencing matters: services must be coordinated to avoid clashes before plastering.
Trades on site
Deliverables
Risk note
Plaster needs proper drying time (1 week per coat) — rushing this stage risks cracking and finish defects.
Trades on site
Deliverables
Risk note
Specification of fittings should be locked before week 8 to avoid lead-time delays.
Trades on site
Deliverables
Risk note
Stone worktops require templating after units are installed — adds 2 weeks lead time.
Trades on site
Deliverables
Risk note
Final 5% of works always takes 20% of effort. Defect-free handover requires methodical snagging.
Case studies
Three recent projects showing how briefs, budgets, and constraints translate into delivered outcomes for Crouch End Broadway properties.
Duration
18 weeks on site
Budget
£185,000 – £220,000
Scope
Whole-house house extensions of a 4-bed period property: full rewire, replumb, new kitchen, three bathrooms, and bespoke joinery throughout.
Before
Tired 1990s refit with worn carpets, dated bathrooms, single-glazed sashes, and a leaking flat roof. EPC rating D.
After
Premium family home with restored period features, premium kitchen and bathrooms, smart-home integration, and EPC rating C.
Challenge
Conservation-area consent required for sash window upgrades and new dormer at rear. Family wanted to remain in property for first 4 weeks.
Solution
Phased works with ground-floor rooms completed first as habitable zone. All planning consent secured before strip-out.
"They handled the conservation officer brilliantly and the period detailing is better than the original. We could not be happier."
Duration
12 weeks on site
Budget
£95,000 – £125,000
Scope
Premium flat house extensions: full rewire, replumb, new kitchen, two bathrooms, acoustic insulation, and managing-agent coordination.
Before
Tired 1980s refit, electric storage heaters, no acoustic insulation, dated kitchen and bathrooms.
After
Premium apartment with new gas central heating, acoustic insulation, designer kitchen, and stone bathrooms. EPC C.
Challenge
Strict managing-agent rules: 8am–5pm working hours, lift bookings, no Saturday work, deposit £5k for communal-area damage.
Solution
Detailed method statement and risk assessment submitted upfront. Lift and porter slots booked weeks ahead. Communal areas protected daily.
"The managing agent said they'd never seen a contractor coordinate so well. Worth every penny for that alone."
Duration
22 weeks on site
Budget
£235,000 – £275,000
Scope
Side-return extension, full kitchen replacement, ground-floor reconfiguration, plus full upstairs refurbishment.
Before
Closed-off Victorian layout with narrow galley kitchen, cellular reception rooms, and tired upstairs bathrooms.
After
Open-plan kitchen-dining-family living across rear, restored front reception, three new bathrooms, and converted loft bedroom.
Challenge
Permitted-development limits, party wall agreement with two neighbours, and a tight side-return access.
Solution
Crane delivery for steels over rear roof. Both party wall agreements secured pre-start. Architect-led design package.
"They turned a tired family house into the home of our dreams without losing the character. Best decision we made."
Find answers to common questions about our services.
More price routes
These guides use the same transparent structure, so you can compare scope and budget before building a broader project brief.
Crouch End Broadway
Complete property refurbishment from strip-out through services, finishes, and handover.
From £60,000
Crouch End Broadway
Whole-house refurbishment for London family homes and period properties.
From £30,000
Crouch End Broadway
Flat refurbishment for mansion blocks, period conversions, and modern apartments.
From £25,000
Crouch End Broadway
Kitchen renovation including layout planning, installation, finishes, and service coordination.
From £18,000
Crouch End Broadway
Bathroom renovation covering strip-out, waterproofing, fixtures, tiling, and finishing.
From £10,000
Crouch End Broadway
Loft conversions including rooflight, dormer, mansard, and L-shaped layouts.
From £40,000
Speak to the office
Call the office for budgeting and programme guidance, or send your brief for a fuller written quotation. We will explain what is included, what can move cost, and which tier best fits your property.
Typical start point
£45,000
Published rating
4.9 / 5
Across 183 published reviews.
Best first call
Office for budgeting, mobile for quick response