House Extension
in Harlow
Compare quotes from vetted Harlow extension builders for single-storey, double-storey and rear extensions. Transparent pricing from £17,500. Free, no-obligation quotes — results in 24 hours.
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How Much Do House Extension Cost in Harlow?
Real prices from completed projects in Harlow and the surrounding area. Costs vary by size, specification and access — use these as a starting guide, then get 3 free quotes for your specific project.
The most popular choice for UK terraces and semis. Adds a kitchen-diner or extra living space at ground level. Typically 3–5m deep, completed in 10–14 weeks.
Get quotes for this →Maximum space gain in a single build — adds a ground-floor room and a bedroom above. Strong ROI in most UK property markets. Requires full planning permission.
Get quotes for this →Ideal for terraced homes with a narrow side alley. Transforms a cramped kitchen into a full-width open-plan space. Often combined with a rear extension.
Get quotes for this →Costs depend on size, spec and access. The best way to know your exact price is to compare 3 quotes from vetted local specialists.
Get free quotes →Harlow pricing note: Eastern England (Essex, Hertfordshire, Cambridgeshire, Suffolk, Norfolk) runs approximately 8–12% above the national average, influenced by proximity to London and strong demand in commuter towns. Prices shown are indicative ranges for Harlow and Eastern. Always get at least 3 written quotes before committing to any builder.
House Extension Specialists Who Know Harlow
Home renovation activity in Harlow continues to grow year on year. The area's varied housing stock, from older stone-built properties to new-build estates, means there is always strong demand for skilled, experienced local builders.
Before any builder appears on our Harlow platform, we carry out a full vetting check covering public liability insurance, trade qualifications, company registration and verified customer feedback. Only builders who pass every stage are listed.
Our Harlow builder network covers extensions, loft conversions, kitchens, bathrooms, roofing, driveways and more. Get up to 3 free, no-obligation quotes within 24 hours and choose the builder that best fits your project and budget.
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What Harlow Homeowners Say About Our House Extension Specialists
Two-storey rear extension on our 1970s detached in Harlow. New oak Crittall-style steel doors as the threshold detail - looks expensive. Quote of £61800 held to within 1%. Snagging fully resolved within 14 days of completion.
Compared four extension builders through BestBuilders for the Harlow job. Picked the team with the longest insurance-backed structural warranty. Trade plates on the kerb so the council parking team did not bother them. £68000 fitted, 12-week site programme. Family of four lived in throughout - we managed.
Five months later and the connection between old house and new feels seamless. Builder we found via BestBuilders in Harlow argued for thicker insulation in the slab - heating bills are visibly lower year-round. Total £62400. Best decision we have made on this house.
House Extension in Harlow — FAQs
Plan Your house extension Project in Harlow
Whether you're researching costs, checking planning rules, or comparing approaches before you commit, our editorial team has produced these guides to help Harlow homeowners make informed decisions about their house extension project.
House Extension Cost Guide
Detailed UK price ranges, regional adjustments and worked examples for house extension projects.
Read House Extension Cost Guide →All House Extension Specialists
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Browse House Extension Specialists →All Cost Guides
Compare prices across extensions, lofts, kitchens, bathrooms, roofing, driveways and solar projects.
View All Cost Guides →Planning your house extension project? Read these guides:
House Extension Near Harlow
We also connect homeowners with vetted house extension specialists in towns surrounding Harlow.
Planning Your House Extension in Harlow
Before you compare quotes, it's worth understanding the full UK price picture for house extension and how Harlow sits within it. The guides below cover average costs, what affects your quote, and how to choose a builder you can trust.
UK House Extension Cost Guide
Full price ranges, worked examples and the factors that move your quote — drawn from real project data across 519 UK towns.
Read the house extension cost guide →House Extension Across the UK
Browse house extension services nationwide, see what's typical in your region, and request quotes from any UK location.
Visit the UK house extension hub →Planning Permission for House Extension in Harlow
Find out whether your house extension needs planning permission in Harlow, what Permitted Development limits apply, and how rules differ in conservation areas, Article 4 zones, and listed-building settings.
Read the house extension planning rules →More homeowner resources: all UK building guides, cost guides, planning permission, comparisons, how-to guides and industry insights.