Summer 2026 is the ideal time for extensions. Dry weather and long days mean faster completion and fewer delays.

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Find a Extension Builder Near You

Updated May 2026Prices verified 6 May 2026200 UK cities covered

A extension builder in the UK typically costs £15,000–£50,000 in 2026. TradeMatch connects homeowners with vetted, insured extension builder professionals across 200 UK locations. Post your job free, compare up to 5 quotes, and pay securely through escrow protection.

Single and double storey house extensions and side returns. Compare quotes from vetted extension builder professionals across the UK. Typical cost: £15,000–£50,000.

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Professional extension builder at work in the UK

Quick answer

What does an extension builder do, and what does it cost in the UK?

An extension builder handles groundwork, structure, roof and finishing for a single- or double-storey home extension. UK 2026 typical cost: £1,500–£2,500 per m² (London: +30–40%). A 4×5m single-storey rear runs £30,000–£60,000. Most need Building Regs approval; some need full planning permission. Allow 10–14 weeks for single, 14–20 for double.

Extension builder vs general builder vs loft converter

JobExtension builderGeneral builderLoft converter
Single-storey rear extension✅ Recommended⚠️ Variable quality❌ Out of scope
Double-storey side return✅ Recommended⚠️ Variable quality❌ Out of scope
Loft conversion⚠️ Some⚠️ Variable quality✅ Recommended
Garage conversion✅ Yes✅ Yes⚠️ Sometimes
Internal renovation⚠️ Possible✅ Recommended❌ Out of scope

Use a builder who specialises in extensions for anything structural. A specialist coordinates planning, structural engineer, party-wall surveyor and Building Control on your behalf.

The Complete Guide to Hiring a Extension Builder in 2026

A extension builder provides single and double storey house extensions and side returns. Whether you need routine maintenance, emergency repairs, or a major installation project, a qualified extension builder has the skills, tools and experience to complete the work safely and to a high standard. On TradeMatch, every extension builder is vetted, background-checked, and holds verified public liability insurance — giving you peace of mind that your project is in safe hands.

When Should You Hire a Extension Builder?

  • •You notice something that needs professional extension builder attention — don't wait for small issues to become expensive problems.
  • •You're planning a renovation or home improvement project that requires specialist extension builder skills.
  • •You need work that must comply with UK building regulations, safety standards, or manufacturer warranties.
  • •You want a professional assessment, survey or quote before committing to a larger project.
  • •You need ongoing maintenance to keep your property in good condition.

Extension BuilderQualifications & Credentials to Look For

When hiring a extension builder, always verify their qualifications. The following are the key credentials and trade body memberships regulated by Relevant trade association:

✓Relevant trade qualifications
✓Public liability insurance
✓Valid public liability insurance (minimum £1M)

On TradeMatch, we verify all of these credentials before any extension builder can quote on jobs.

Verified Credentials

UK accreditations every extension builder on TradeMatch is checked against

Every tradesperson is verified against the UK accreditation bodies that matter for the work — before they can quote.

Read the full UK accreditations guide →

Extension Builder tools and workmanship — UK trade professional

Extension Builder Hiring Checklist

Use this checklist before hiring a extension builder to ensure you get quality work at a fair price:

  1. 1Verify qualifications: Relevant trade qualifications
  2. 2Confirm valid public liability insurance (minimum £1 million cover)
  3. 3Check reviews from previous customers — look for consistent quality and reliability
  4. 4Get at least 3 written quotes that itemise labour, materials and VAT
  5. 5Ask for references and examples of similar completed work
  6. 6Agree a detailed scope of work and timeline in writing before work starts
  7. 7Confirm payment terms — TradeMatch escrow protects both homeowner and tradesperson
  8. 8Check whether Building Control notification or planning permission is required

Red Flags When Hiring a Extension Builder

Watch out for these warning signs when getting quotes for extension builder work:

  • ✗No verifiable qualifications or trade body membership
  • ✗Requests full payment upfront before any work has started
  • ✗No public liability insurance or unwilling to provide proof
  • ✗Pressures you to make a quick decision without time to compare quotes
  • ✗Cannot provide references or examples of previous work
  • ✗Unusually low quotes that seem too good to be true

TradeMatch eliminates these risks — every extension builder is vetted, insured, and payments are escrow-protected.

Best Time to Hire a Extension Builder

You can hire a extension builder at any time of year, but planning ahead and booking during off-peak months (typically late autumn to early spring) can help you get better availability and potentially lower prices. For emergency work, TradeMatch has professionals available for same-day callouts.

Looking for a Extension Builder Near You?

Browse vetted extension builder professionals across 200 UK cities.

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Average Extension Builder Costs in 2026

JobLowAverageHigh
Small job£80£200£400
Medium job£300£700£1,500
Large job£1,000£2,500£5,000
Consultation/survey£50£100£250
Emergency callout£80£150£300

Prices are estimated UK averages for 2026. Actual costs vary by location, materials and scope of work.

Extension Builder Services

Single Storey Extension

Rear, side and wrap-around single storey extensions under permitted development

£15,000–£40,000

Double Storey Extension

Two storey extension with planning application, structural design and full build

£30,000–£80,000

Kitchen Extension

Open-plan kitchen-diner extension with bi-fold doors and roof lantern

£20,000–£50,000

Find a Extension Builder by Location

LondonGreater LondonBirminghamWest MidlandsManchesterGreater ManchesterLeedsWest YorkshireGlasgowGlasgow CityLiverpoolMerseysideNewcastleTyne and WearSheffieldSouth YorkshireBristolBristolEdinburghCity of EdinburghCardiffSouth GlamorganBelfastCounty AntrimNottinghamNottinghamshireLeicesterLeicestershireCoventryWest MidlandsBradfordWest YorkshireStoke-on-TrentStaffordshireWolverhamptonWest MidlandsPlymouthDevonSouthamptonHampshireReadingBerkshireDerbyDerbyshireAberdeenAberdeenshireSwanseaWest GlamorganOxfordOxfordshireCambridgeCambridgeshireYorkNorth YorkshireBathSomersetNorwichNorfolkPortsmouthHampshireBrightonEast SussexHullEast Riding of YorkshireSunderlandTyne and WearDundeeDundee CityMiddlesbroughNorth YorkshireExeterDevonPeterboroughCambridgeshireCheltenhamGloucestershireGloucesterGloucestershireLincolnLincolnshireSalisburyWiltshireChesterCheshireWorcesterWorcestershireInvernessHighlandLutonBedfordshireIpswichSuffolkBlackpoolLancashireBoltonGreater ManchesterWarringtonCheshireCrawleyWest SussexColchesterEssexBasingstokeHampshireMaidstoneKentBedfordBedfordshireNorthamptonNorthamptonshireSwindonWiltshireWiganGreater ManchesterMansfieldNottinghamshireWakefieldWest YorkshireBarnsleySouth YorkshireDoncasterSouth YorkshireRotherhamSouth YorkshireGrimsbyLincolnshireScunthorpeLincolnshireHarrogateNorth YorkshireScarboroughNorth YorkshireCarlisleCumbriaBarrow-in-FurnessCumbriaLancasterLancashireBurnleyLancashirePrestonLancashireStockportGreater ManchesterOldhamGreater ManchesterRochdaleGreater ManchesterBirkenheadMerseysideSt HelensMerseysideWalsallWest MidlandsDudleyWest MidlandsSolihullWest MidlandsTelfordShropshireShrewsburyShropshireHerefordHerefordshireKidderminsterWorcestershireStaffordStaffordshireTamworthStaffordshireNuneatonWarwickshireRugbyWarwickshireKetteringNorthamptonshireCorbyNorthamptonshireWellingboroughNorthamptonshireBanburyOxfordshireAylesburyBuckinghamshireHigh WycombeBuckinghamshireMilton KeynesBuckinghamshireStevenageHertfordshireWatfordHertfordshireSt AlbansHertfordshireChelmsfordEssexSouthend-on-SeaEssexGuildfordSurreyTunbridge WellsKentCanterburyKentDoverKentFolkestoneKentAshfordKentMargateKentDartfordKentHastingsEast SussexEastbourneEast SussexWorthingWest SussexChichesterWest SussexHorshamWest SussexWokingSurreySloughBerkshireMaidenheadBerkshireNewburyBerkshireBracknellBerkshireWinchesterHampshireAndoverHampshireFarehamHampshireGosportHampshireAldershotHampshireFarnboroughHampshireTauntonSomersetYeovilSomersetTorquayDevonBarnstapleDevonTruroCornwallTrowbridgeWiltshireChippenhamWiltshireDorchesterDorsetWeymouthDorsetBournemouthDorsetPooleDorsetKings LynnNorfolkGreat YarmouthNorfolkBury St EdmundsSuffolkLowestoftSuffolkHarlowEssexBraintreeEssexBasildonEssexGraysEssexHemel HempsteadHertfordshireHitchinHertfordshireWelwyn Garden CityHertfordshireLetchworthHertfordshireChesterfieldDerbyshireLoughboroughLeicestershireHinckleyLeicestershireGranthamLincolnshireBostonLincolnshireNewark-on-TrentNottinghamshireWorksopNottinghamshireBuxtonDerbyshireCannockStaffordshireLichfieldStaffordshireBurton upon TrentStaffordshireLeamington SpaWarwickshireStratford-upon-AvonWarwickshireRedditchWorcestershireBromsgroveWorcestershireGreat MalvernWorcestershireCreweCheshireMacclesfieldCheshireCongletonCheshireWidnesCheshireRuncornCheshireKendalCumbriaPenrithCumbriaAccringtonLancashireChorleyLancashireLeighGreater ManchesterSaleGreater ManchesterBuryGreater ManchesterAshton-under-LyneGreater ManchesterFleetwoodLancashireDarlingtonCounty DurhamDurhamCounty DurhamBishop AucklandCounty DurhamHartlepoolCounty DurhamBlythNorthumberlandHexhamNorthumberlandWhitbyNorth YorkshireRiponNorth YorkshireNorthallertonNorth YorkshireSelbyNorth YorkshireGooleEast Riding of YorkshireBeverleyEast Riding of YorkshireBridlingtonEast Riding of YorkshireNewportGwentWrexhamWrexhamLlanelliCarmarthenshireAberystwythCeredigionBangorGwyneddStirlingStirlingshirePerthPerth and KinrossFalkirkFalkirkDunfermlineFifeKirkcaldyFifeAyrSouth Ayrshire

Extension Builder — Frequently Asked Questions

How much does a extension builder cost in the UK?▾
The typical cost for a extension builder in the UK ranges from £15,000–£50,000. Prices vary depending on the scope of work, materials needed, your location and the tradesperson's experience. London and the South East are typically 20–40% more expensive. Get free, no-obligation quotes on TradeMatch to compare prices in your area.
How do I find a reliable extension builder near me?▾
On TradeMatch UK, every extension builder is vetted, background-checked and reviewed by real homeowners. Simply post your job, receive up to 5 quotes from local professionals, then compare reviews, qualifications and pricing before choosing who to hire. All payments are escrow-protected.
What qualifications should a extension builder have?▾
A reputable extension builder should hold: Relevant trade qualifications, Public liability insurance. They should also carry public liability insurance. The relevant regulatory body is Relevant trade association. On TradeMatch, we verify these credentials before any tradesperson can join the platform.
How long does it take to get a extension builder on TradeMatch?▾
Most homeowners receive their first quote within a few hours of posting a job. Depending on demand in your area, you can typically have a extension builder booked within 1–3 days for standard work, or same-day for emergencies.
Are extension builder professionals on TradeMatch insured?▾
Yes. Every extension builder on TradeMatch must hold valid public liability insurance before they can quote on jobs. We verify insurance documentation as part of our vetting process, and payments are escrow-protected — your money is only released when you confirm the work is satisfactory.
How much does a extension builder charge per hour?▾
Hourly rates for a extension builder in the UK typically range from £80 to £400 depending on the job complexity and location. London rates are 20–40% higher than the national average. Many extension builder professionals prefer to quote per job — post on TradeMatch for accurate fixed-price quotes.
What guarantee should a extension builder offer?▾
A reputable extension builder should offer a written guarantee of at least 12 months on labour. For larger projects, look for guarantees backed by Relevant trade association or an insurance-backed warranty. On TradeMatch, all payments are escrow-protected and every tradesperson is vetted.
Is it worth hiring a extension builder or doing it myself?▾
For small cosmetic tasks you may be able to DIY, but for anything requiring relevant trade qualifications it's safer to hire a qualified extension builder. Incorrect work can void insurance, fail inspections, or cause expensive damage. Compare free quotes on TradeMatch before deciding.
What extension builder services can I book on TradeMatch?▾
Extension Builder services on TradeMatch include: Single Storey Extension, Double Storey Extension, Kitchen Extension. Each service has vetted specialists. Post your specific job to get quotes from professionals who specialise in exactly what you need.

How to Hire a Extension Builder on TradeMatch

1

Post Your Job

Tell us what extension builder work you need — it only takes 2 minutes.

2

Get Free Quotes

Receive up to 3 quotes from vetted extension builder professionals near you.

3

Hire & Review

Compare reviews, choose the best quote, and leave a review when the job is done.

Extension BuilderQuestions & Answers

Browse questions from homeowners about hiring a extension builder, costs, and what to expect.

Browse Extension BuilderQ&A →Extension BuilderCost Guide →How to Hire a Extension Builder→

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How TradeMatch wins for Extension Builder work

Side-by-side with the four most-searched UK trade platforms. No subscription fees, up to 5 competing quotes, escrow-protected payments — three things every other platform misses.

FeatureTradeMatchCheckatradeMyBuilderBarkRated People
Up to 5 quotes✓BrowseUp to 5VariesUp to 3
Escrow payment protection✓✗✗✗✗
No tradesperson subscription✓£50+/mo✓Credits£15+/mo
Verified reviews (live)✓5-day delay✓Mixed✓
Background + qualification checks✓✓LightBasic ID✓
Dispute resolution team✓✗✗✗✗
See full platform comparison →Post a extension builder job free