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EC1 · EC2 · EC3 · EC4

BuilderrinCityofLondon.

Limited residential stock; primarily apartment fit-outs and listed building work.

Quick answer

Builderr delivers high-end apartment refurbishments, listed-building interior works and Barbican-style flat remodels across the City of London — EC1, EC2, EC3 and EC4. Residential stock is concentrated at the Barbican Estate, Golden Lane Estate, Middlesex Street Estate and a handful of conversions around Smithfield, St Paul's and Aldgate. Almost every project requires planning permission, Listed Building Consent or estate-level approval; external alterations are very rarely possible. Our team specialises in interior reconfigurations, kitchen and bathroom remodels, and acoustic upgrades that meet the City's strict standards.

About the area

Local context for City of London builds.

City of London covers postcodes EC1, EC2, EC3, EC4. We've delivered residential construction projects across nearly every street here since 2022 — loft conversions, side-return and rear extensions, double-storey extensions, kitchen and bathroom renovations, full whole-house refurbishments, and a small number of new-build infill homes.

Limited residential stock; primarily apartment fit-outs and listed building work. Our local project manager for this borough has detailed knowledge of the planning department's preferences, the conservation area boundaries, the common construction details for the prevailing housing stock, and which side streets accept skip permits without issue.

Quotes for City of London projects are fixed-scope after a site survey, valid for 60 days, and never carry provisional sums or open-ended day rates. Every project includes our 10-year structural warranty and 12-month defects period.

Build types in City of London

Specialised types popular here.

Dormer Loft Conversion
Dormer Loft Conversion in City of London

The London standard. Rear dormers add a full-height bedroom + ensuite under permitted development on most terraces.

Mansard Loft Conversion
Mansard Loft Conversion in City of London

The premium loft. Vertical rear wall + 70-degree slate roof. Maximum floor area on Georgian and Victorian terraces.

Hip-to-Gable Loft Conversion
Hip-to-Gable Loft Conversion in City of London

The semi-detached upgrade. Replace the hipped side roof with a vertical gable wall to unlock a full dormer behind.

L-Shape Loft Conversion
L-Shape Loft Conversion in City of London

The Victorian terrace specialist. Build a dormer over both the main roof and the rear closet wing for two bedrooms + bathroom.

Velux Loft Conversion
Velux Loft Conversion in City of London

The cheapest, fastest loft. Insulate the existing roof, install rooflights, and add a fire-rated stair — no roof alteration.

Side Return Extension
Side Return Extension in City of London

The classic kitchen-diner extension. Fill the side alley of a Victorian terrace for a 3–4m wider open-plan kitchen.

Rear Extension
Rear Extension in City of London

Extend the back of the house up to 6m under the prior approval route. Open-plan kitchen-diner with garden views.

Wraparound Extension
Wraparound Extension in City of London

Side return + rear extension combined into one L-shape ground floor. Largest single-storey footprint without going double-storey.

Double-Storey Extension
Double-Storey Extension in City of London

Two floors of extension — bigger kitchen below, extra bedroom + bathroom above. The full upsize without moving.

Kitchen Extension
Kitchen Extension in City of London

Extension build plus full kitchen fit-out in one fixed-price project. Open-plan kitchen-diner with bifold doors and roof lantern.

Integral Garage Conversion
Integral Garage Conversion in City of London

Convert an attached garage to a bedroom, office or living room. No new foundations or external walls. From £25,000 in 4–8 weeks.

Detached Garage Conversion
Detached Garage Conversion in City of London

Transform a detached outbuilding into annexe, home office, studio or garden room. Independent from main house, own entrance.

Load-Bearing Wall Removal
Load-Bearing Wall Removal in City of London

Open up your ground floor — steel beam install, structural calcs, building regs and party wall, fixed-scope.

RSJ Installation
RSJ Installation in City of London

Steel beam supply and install for openings, extensions and structural alterations — engineer-signed, building-regs certified.

Underpinning
Underpinning in City of London

Strengthen existing foundations — for subsidence repair, basement excavation or load increase. Engineer-led, building-regs compliant.

Cellar Conversion
Cellar Conversion in City of London

Convert your existing under-house cellar into a habitable home office, utility, gym or guest room — no excavation needed.

Full Basement Excavation
Full Basement Excavation in City of London

Create a new basement under your existing house — full excavation, underpinning, waterproofing and habitable fit-out.

Basement Extension
Basement Extension in City of London

Add basement floor area beyond the existing house footprint — sub-garden excavation with light wells for cinema, gym, spa.

Planning in City of London

Local planning rules and conservation areas.

The City of London is the smallest and one of the most planning-restrictive authorities in the UK. The Barbican Estate is Grade II listed (with Grade II* elements) and the Golden Lane Estate is Grade II listed — both with Article 4 directions removing all permitted development rights. Conservation areas cover virtually the entire Square Mile including Smithfield, St Paul's, Bank, Whitefriars, Postman's Park, Fleet Street and the Tower environs. External alterations, new openings, replacement windows and even some internal works to listed flats require Listed Building Consent. The City's Local Plan and Heritage SPD require pre-application engagement; consultation with the Barbican Listed Building Management Guidelines is essential for any Barbican project. Tall building policy, protected viewing corridors (LVMF) and St Paul's Heights add further constraint. Determination times are slower than outer London — typically 10–12 weeks with extensive officer engagement.

Every quote we issue for City of London includes a free desk-based planning assessment of your specific address — we tell you whether your project is permitted development, prior approval, or full planning before you sign anything. Our planning team handles the full submission including drawings, Design and Access Statements, and pre-application consultation where required.

Compare

Builderr vs other London builders.

The construction industry has a wide distribution of operators. Here's what changes between a directly-employed, fixed-scope outfit and the alternatives.

Builderr fixed price
£120,000
a City of London project · no provisional sums
Typical builder + variations
£144,000
+£24,000 vs Builderr (≈20% overrun)
Cowboy outfit + cost creep
£174,000
+£54,000 vs Builderr (≈45% overrun)
CriterionBuilderrTypical London builderCowboy outfit
Labour modelDirectly employed team (PAYE)Mixed subcontract gangsDay-rate cash labour
PricingFixed-scope itemised quoteEstimate + provisional sumsVerbal price + variations
Design & engineeringIn-house architect + SEOutsourced, separate billingBuilder draws on the back of an envelope
Planning + LDC handledYes — included in priceOften charged extraBuilder asks you to apply
Party wall surveyorsInstructed by usYour responsibilitySkipped (illegal)
Building controlPlans + site inspections booked by usBuilding Notice routeNot registered
Project managementDedicated PM, weekly photo updatesForeman doubles upOwner-manager juggles 5 jobs
Payment scheduleStage payments against signed-off milestonesWeekly invoicesCash up front
Insurance£10M PL + 10yr structural warranty£2–5M PL onlyNo documented cover
Snags at handover<3 typical20–30 typicalWalk-off mid-job common
Variation creep0% — fixed scope+15–25% over original quote+40%+ regularly
Bottom line

Save £24,000£54,000 on a City of London project.

Industry data (FMB, RICS, Which? Trusted Trader 2024) shows the average London construction project overruns by 18–22% on cost and 25–35% on time. Fixed-scope contracts with a single accountable team eliminate that variance. The savings above assume a typical project at £120,000.

FAQ

City of London questions, answered.

Do you cover all of City of London?+

Yes — every postcode within City of London is within our standard coverage zone. We've delivered projects in nearly every postcode of the borough since 2022.

How do planning rules differ in City of London?+

City of London's planning authority maintains a local plan and conservation area register that differ from the national permitted development baseline. We run a free desk-based planning assessment of your address before quoting so you know whether your project is PD or needs full planning.

How long does a typical City of London project take?+

Bathroom renovations 2–5 weeks, kitchen renovations 3–8 weeks, loft conversions 8–14 weeks, single-storey extensions 10–18 weeks, double-storey or wraparound extensions 16–22 weeks, full house renovations 16–36 weeks. Programme is fixed at contract sign and tracked weekly.

Do you have references in City of London?+

Yes — we maintain a live reference list per borough. We can connect you with two or three completed clients in City of London for an unfiltered conversation about working with us.

Ready to build in City of London?

Senior consultant call within one business hour. Free desk-based planning assessment for EC1, EC2, EC3 and surrounding postcodes.