Typical total range
£42,250 - £177,450
For fixed-price components of a typical home extension project in Primrose Hill.
Cost GuidePrimrose Hill
Home Extension Cost in Primrose Hill
Find out how much home extension costs in Primrose Hill. This guide turns the raw price table into a more usable local budgeting view, with clearer ranges, local adjustment notes, and direct office support when you need a firmer quote.
£42,250 - £177,450Local multiplier 1.30xBudget, mid-range, premium bands
Area-adjusted pricing
This guide applies a 1.30x local multiplier where area-specific pricing evidence exists for Primrose Hill.
Transparent allowances
Budget, mid-range, and premium bands are shown together so scope decisions are clearer before you request a quote.
Office-first support
Call the office for budgeting, specification, and scheduling advice before you lock the project brief.
Project pace
Prompt quote response
We can review the brief quickly, then refine the commercial detail after survey and scope confirmation.
Best first call
Office for planning, mobile for quick response
Use the office line when you want a proper budgeting conversation rather than a fast callback only.
Fully insured
£5M public liability
Established 2010
14+ years North London
10-year guarantee
Workmanship + insurance backed
4.9 / 5
183+ verified reviews
Home Extension Price Breakdown in Primrose Hill
| Item | Budget | Mid-Range | Premium | Notes |
|---|---|---|---|---|
| Architecture & planning | £3,900 | £7,800 | £15,600 | - |
| Structural engineer | £1,950 | £3,250 | £5,850 | - |
| Foundations & groundworks | £10,400 | £18,200 | £36,400 | - |
| Shell construction (per sqm) | £2,860 /per sqm | £3,900 /per sqm | £5,850 /per sqm | - |
| Glazing (bifolds/sliders) | £5,200 | £15,600 | £39,000 | - |
| Roofing & insulation | £5,850 | £10,400 | £20,800 | - |
| Electrical & plumbing | £4,550 | £8,450 | £15,600 | - |
| Plastering & decoration | £3,250 | £6,500 | £11,700 | - |
| Flooring | £1,950 | £5,200 | £11,700 | - |
| Project management | £5,200 | £10,400 | £20,800 | - |
Local adjustment note
Ultra-prime expectations.
What Affects Home Extension Cost in Primrose Hill?
high impact
Extension size (sqm)
Cost typically £2,200-£4,500 per sqm for the shell, more for fit-out.
high impact
Storey count
Double-storey is more cost-efficient per sqm than single-storey.
high impact
Glazing extent
Large bifolds, sliding doors, and rooflights add £8-30k.
medium impact
Planning route
Permitted development is faster; full planning needed for larger or conservation builds.
high impact
Foundations
Mass-fill vs piled vs raft depending on ground and trees.
high impact
Specification of fit-out
Mid-range vs prime kitchen, flooring, joinery.
Included in Our Quotes
- Architectural design and Building Control package
- Structural engineering coordination
- Planning application submission and management
- Party Wall coordination
- Full build to wind-and-watertight
- Fit-out and finish to agreed specification
Not Included By Default
- Planning consultancy fees (separate)
- Party Wall surveyor fees
- Tree surveys and arboricultural reports
- Underpinning of neighbouring properties
- Landscaping and external works
- Furniture and styling
Money-Saving Tips for Home Extension in Primrose Hill
Stay within Permitted Development limits where possible — saves 8-12 weeks vs full planning.
Single-storey full-width rear extensions often produce the best value-per-sqm.
Use proprietary roof glazing rather than bespoke structural glass for cost-effective light.
Specify the kitchen and flooring as part of the contract to lock pricing early.
Combine with internal reconfiguration to share scaffolding and crew mobilisation.
From Brief to Move-In Day in Primrose Hill
An 8-stage process refined over 14+ years of home extension delivery across North London. Every stage has a single point of contact and a clear deliverable.
1
Initial enquiry
Within hours we discuss scope, budget, and access constraints in Primrose Hill.
2
Free site survey
On-site visit to assess property condition, services, and any heritage considerations.
3
Detailed brief
We document scope, specification, allowances, and exclusions for transparent pricing.
4
Fixed-price quote
Itemised written quote, broken down by trade and stage, with tier options.
5
Planning & approvals
We handle Building Control, Party Wall, and any conservation-area consents.
6
Site mobilisation
Site protection, deliveries, scaffolding, and crew induction set up before strip-out.
7
Build delivery
Sequenced works under one project manager with weekly progress reporting.
8
Snagging & handover
Defect-free handover, certificates, and a 12-month aftercare period.
Home Extension Building Regulations in Primrose Hill
Building Control sign-off is included in our quotes. Typical compliance touchpoints for home extension projects:
Part P
Electrical safety
Documented sign-off for new circuits and consumer-unit upgrades where they form part of the agreed scope.
Part L
Energy efficiency
Insulation, glazing, heating, and ventilation upgrades to current standards.
Part B
Fire safety
Means-of-escape, fire-rated doors and walls, and smoke alarm placement.
Part E
Sound insulation
Acoustic separation between flats and within converted houses.
Primrose Hill planning context
Ultra-prime expectations. We coordinate any additional consents required for conservation areas, listed buildings, or Article 4 zones in Primrose Hill.
What Clients Say About Our Home Extension
4.9 / 5 from 183+ verified reviews on Google, Checkatrade, and Houzz
“Absolutely transformed our Victorian terrace in Hampstead. The attention to period detail was exceptional. They restored our original cornices and installed a stunning new kitchen. Highly recommend for anyone with a period property.”
— Sarah M.
Hampstead, NW3
“Had our entire house rewired by HAMPSTEAD RENOVATIONS. Clean, professional work with minimal disruption. They were careful around our period features and the plastering afterwards was perfect.”
— James R.
Belsize Park, NW3
“Emergency boiler repair on a Sunday - arrived within an hour and fixed the issue quickly. Fair pricing and no callout fee gouging. Will definitely use again.”
— Emily T.
Highgate, N6
Interactive estimator
Home Extension Cost Calculator for Primrose Hill
Drag the slider to set your floor area and pick a specification tier. The estimate updates live using Primrose Hill-specific pricing data.
80 sqm
30 sqm (small flat)400 sqm (large house)
Specification tier
Designer fixtures, bespoke joinery, premium worktops, smart-home pre-wire.
£1,373 / sqm at premium tier × 1.30 Primrose Hill multiplier
Estimated total
£142,792
Likely range: £128,513 – £164,211
Base (Premium × 80 sqm)£109,840
Primrose Hill multiplier× 1.30
Adjusted total£142,792
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
Home Extension Specification by Room in Primrose Hill
Every home extension project breaks down into rooms with different scopes, costs, and durations. Below is the typical specification we deliver across Primrose Hill properties.
Kitchen
Bespoke or premium-fit kitchen in Primrose Hill 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
- Survey-led design with 3D visualisations
- Premium quartz, marble, or sintered-stone worktops
- Integrated Miele, Siemens, Bosch, Wolf or Sub-Zero appliances available
- Concealed extraction routed to comply with conservation-area facade controls
- Bespoke joinery for pantries, breakfast bars, and built-in seating
Bathrooms
Family bathrooms, en-suites, and cloakrooms designed for Primrose Hill property layouts. Stone, mosaic, large-format, or wet-room solutions.
Typical cost
£8,000 – £28,000 per room
Duration
2 – 4 weeks per room
- Premium British, Italian, and German sanitaryware ranges
- Underfloor heating with insulated screed and digital thermostats
- Large-format porcelain, stone, marble, or tadelakt finishes
- Walk-in showers with framed or frameless glass enclosures
- Acoustic insulation between flats where required by lease
Living Areas
Open-plan reception, dining, and family spaces. Where structure permits we open through party walls with steel beams to maximise light and flow in Primrose Hill period properties.
Typical cost
£10,000 – £35,000
Duration
4 – 6 weeks
- Engineered-oak or stone flooring throughout open-plan layouts
- Period cornicing, ceiling roses, and architraves restored or re-cast
- Bespoke media walls, joinery, and built-in storage solutions
- Smart lighting circuits with scene control and dimming throughout
- Tall slim-frame doors and crittall-style internal glazing
Bedrooms
Master suites, family bedrooms, and study/guest rooms. Built-in storage, lighting, smart-home pre-wire, and acoustic treatments where appropriate for Primrose Hill living patterns.
Typical cost
£4,500 – £18,000 per room
Duration
2 – 3 weeks per room
- Full-height fitted wardrobes with internal lighting and soft-close drawers
- Bedside circuits for USB-C, lamps, and integrated reading lights
- Acoustic insulation in walls and floors for peaceful sleep
- Period sash window restoration with double-glazed slim units
- Integrated dressing rooms and en-suite reconfigurations
Hallways & Stairs
Entrance halls, landings, and stairwells — often the first impression in Primrose Hill 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
- Original timber stair restoration including treads, risers, and handrails
- Encaustic tile floors restored or replaced with reclaimed equivalents
- New panelled doors and bespoke architraves matching period detail
- Period plaster cornicing and dado rails restored
- Modern intercom, smart-lock, and parcel-locker integration
Services & Utilities
Boiler, hot-water cylinder, consumer unit, MVHR, electrical and plumbing infrastructure replaced or upgraded across the property. Often the hidden backbone of a home extension project in Primrose Hill.
Typical cost
£8,000 – £25,000
Duration
2 – 4 weeks (concurrent with other trades)
- Full rewire to current 18th edition standards with NICEIC certification
- Replumb in PEX or copper with manifold distribution
- New boiler, cylinder, and zoned heating with smart controls
- MVHR systems for tightly-sealed retrofits where appropriate
- EV charger and consumer-unit upgrades anticipating future loads
Decision framework
Refurbish or Rebuild: Choosing the Right Approach in Primrose Hill
The biggest single decision on a home extension project is whether to refurbish the existing property or demolish and rebuild. Here's how we frame the trade-offs for Primrose Hill owners.
1How much of the existing structure is sound?
Refurbish
Most Primrose Hill 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.
2What does the planning landscape allow?
Refurbish
Conservation areas in Primrose Hill 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.
3How does the budget compare?
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.
4What is the energy and comfort upgrade gap?
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.
5What about resale value and marketability?
Refurbish
Refurbished Primrose Hill 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
Sequencing Your Home Extension Project
An 18-week home extension project breaks into 8 phases, each with specific trades, deliverables, and risks. Understanding the sequence helps you anticipate questions, decisions, and on-site moments.
Phase 1: Pre-construction
Trades on site
Architect Structural engineer Surveyor Project manager
Deliverables
- Full survey including drains, services, and structural integrity
- Detailed design package with specifications and material schedule
- Planning permission and Building Control submissions where required
- Party Wall agreements coordinated with neighbours
- Fixed-price contract with itemised quote
Risk note
Hidden defects (damp, asbestos, non-compliant additions) are usually discovered here — budget a 10% contingency.
Phase 2: Site setup & strip-out
Trades on site
Site manager Strip-out crew Skip and waste contractors
Deliverables
- Site protection: dust screens, floor coverings, scaffold
- Strip-out of all existing finishes, fittings, and services
- Confirmation of structural condition once exposed
- Asbestos survey and remediation if pre-1999 property
- Final scope confirmation with client
Risk note
Strip-out always reveals more than the survey predicted. Quick decision-making protects programme.
Phase 3: Structural works
Trades on site
Structural engineer Steel fixers Bricklayers Carpenters
Deliverables
- Steel beams, posts, and lintels installed per engineer's design
- Wall removals, openings, and structural alterations
- Foundation works for new walls or extensions
- New floor structures and joist work where required
- Building Control structural inspection and sign-off
Risk note
Steel fabrication lead times can run 4-6 weeks — order early to avoid programme delay.
Phase 4: First-fix services
Trades on site
Electricians Plumbers Heating engineers Insulation contractors
Deliverables
- Full rewire to 18th edition standards with NICEIC certification
- New plumbing in PEX or copper with manifolds
- Heating system installation: boiler, cylinder, MVHR if specified
- Insulation to walls, floors, and roof
- First-fix for AV, smart home, security, and data
Risk note
First-fix sequencing matters: services must be coordinated to avoid clashes before plastering.
Phase 5: Plastering & flooring substrate
Trades on site
Plasterers Floor screeders Carpenters Tilers (substrate)
Deliverables
- Full skim plastering throughout
- Floor screeding with underfloor heating where specified
- Internal stud walls, ceilings, and architectural detailing
- Window and door reveals finished
- Subfloor preparation for finished flooring
Risk note
Plaster needs proper drying time (1 week per coat) — rushing this stage risks cracking and finish defects.
Phase 6: Second-fix services
Trades on site
Electricians Plumbers Heating engineers AV installers
Deliverables
- All sockets, switches, and lighting fittings installed
- Sanitaryware, taps, showers, and radiators connected
- Boiler commissioning and heating zoning configured
- Smart home, AV, and security systems commissioned
- Building Control electrical inspection
Risk note
Specification of fittings should be locked before week 8 to avoid lead-time delays.
Phase 7: Joinery, kitchens & bathrooms
Trades on site
Bespoke joiners Kitchen fitters Stone fitters Tilers
Deliverables
- Bespoke joinery installation: wardrobes, media walls, pantries
- Kitchen units, worktops, splashbacks, and appliances fitted
- Bathroom tiling, sanitaryware, and shower screens
- Internal doors, architraves, and skirting installed
- Stair restoration or replacement completed
Risk note
Stone worktops require templating after units are installed — adds 2 weeks lead time.
Phase 8: Finishing & handover
Trades on site
Decorators Floor finishers Cleaners Snagging team
Deliverables
- Decoration: full mist coat, undercoat, two top coats
- Floor finishes laid: engineered timber, stone, or carpet
- Final clean and snagging walkthrough
- Building Control sign-off and warranty paperwork
- Handover pack with manuals, certificates, and aftercare schedule
Risk note
Final 5% of works always takes 20% of effort. Defect-free handover requires methodical snagging.
Case studies
Home Extension Case Studies in Primrose Hill
Three recent projects showing how briefs, budgets, and constraints translate into delivered outcomes for Primrose Hill properties.
Project 1
Period townhouse home extension in Primrose Hill
Duration
18 weeks on site
Budget
£185,000 – £220,000
Scope
Whole-house home extension 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.
- • EPC rating: D (62)
- • Heating cost: £2,800/year
- • 3 bathrooms (worn)
- • Single-glazed sashes
- • Boiler age: 18 years
After
Premium family home with restored period features, premium kitchen and bathrooms, smart-home integration, and EPC rating C.
- • EPC rating: C (74)
- • Heating cost: £1,400/year
- • 3 premium bathrooms
- • Slim-double-glazed sashes
- • New A-rated combi
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."
Project 2
Mansion-block flat home extension in Primrose Hill
Duration
12 weeks on site
Budget
£95,000 – £125,000
Scope
Premium flat home extension: 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.
- • EPC rating: E (52)
- • Heating cost: £2,200/year
- • No acoustic insulation
- • 2 bathrooms (1 worn)
- • Electric storage heaters
After
Premium apartment with new gas central heating, acoustic insulation, designer kitchen, and stone bathrooms. EPC C.
- • EPC rating: C (76)
- • Heating cost: £950/year
- • Full Part E acoustic insulation
- • 2 stone bathrooms
- • Gas central heating
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."
Project 3
Family extension and refurb in Primrose Hill
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.
- • Floor area: 142 sqm
- • EPC: D
- • Original layout: 7 rooms
- • £0 added value
After
Open-plan kitchen-dining-family living across rear, restored front reception, three new bathrooms, and converted loft bedroom.
- • Floor area: 178 sqm (+25%)
- • EPC: C
- • New layout: 9 rooms
- • £420k added value (estimated)
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."
Home Extension Cost FAQs for Primrose Hill
Find answers to common questions about our services.
Single-storey rear: 12-16 weeks on site. Double-storey or wraparound: 18-26 weeks. Add 8-16 weeks for design, planning and pre-construction.
Many rear extensions fall under Permitted Development, but conservation areas, listed buildings, large extensions, and side extensions usually need full planning. We assess your case at the design stage.
A well-designed extension typically adds 15-25% to property value in prime North London, with the largest uplift on family homes converted to open-plan living.
Home Extension Costs in Other Areas
Speak to the office
Get a sharper home extension quote for Primrose Hill
Use this guide to set the budget range, then call the office for a more accurate quote based on scope, specification, and property constraints in Primrose Hill.
Typical range
£42,250 - £177,450
Area multiplier
1.30x
Based on the pricing evidence available for this area guide.
Response speed
Prompt quotes available