Knowledge base
Londonconstructionguides.
Plain-English guides to planning, party wall, building regulations, warranties and contracting — written by senior project managers who deal with these every day.
Planning
Permitted Development in London: The 2026 Guide
Most loft conversions and rear extensions in London proceed under permitted development — no planning application required. This is what permitted development means in 2026, what it covers, and where it doesn't apply.
Planning
Building in a London Conservation Area: What You Can and Can't Do
Conservation areas cover roughly 25% of London. They preserve the architectural and historic character of an area through additional planning controls. This is what those controls mean for extensions, lofts and renovations.
Regulations
The Party Wall Act in London: A Plain-English Guide
Most London extensions and many loft conversions involve work to a party wall — the wall between you and a neighbour. The Party Wall etc. Act 1996 governs how those works are managed. Here's what it actually means.
Regulations
Building Regulations in London: What Triggers, What Doesn't
Planning permission and building regulations are two separate consents — your project usually needs both. This is what building regulations actually cover, when they apply, and how the inspection process works.
Construction
Structural Warranty for London Construction: What 10 Years Actually Covers
Builderr's 10-year structural warranty is industry-standard but not all warranties are equal. This is what it actually covers, how claims work, and what's excluded.
Construction
Fixed Price versus Day Rate Contracts: Why Pricing Structure Matters
How a contractor prices your job determines how much risk you carry. Fixed-price, fixed-scope is the default for any project over £20,000. This explains why and how it works.
Planning
How to Apply for Planning Permission in London (2026)
A step-by-step guide to submitting a householder planning application in any London borough — what drawings you need, how neighbour consultation works, statutory fees, and realistic decision timelines.
Planning
Article 4 Directions in London: What They Are and How to Check
Article 4 Directions remove permitted development rights in designated areas — meaning you need full planning permission for works that would normally be automatic. Here's how they work, where they apply across London, and how to confirm whether your property is affected.
Planning
Lawful Development Certificate (LDC): Complete Guide for London Homeowners
A Lawful Development Certificate is the council's formal confirmation that your works are lawful — either because they don't need planning permission or because enough time has passed to immunise them from enforcement. Here's when you need one, what it costs, and how to apply.
Planning
Planning Appeal Process in London: Refusal to PINS Decision
When a London borough refuses your planning application, you have a statutory right of appeal to the Planning Inspectorate (PINS). Here's how the process works, what it costs, realistic timelines, and what success rates look like in 2026.
Planning
Listed Building Consent in London: Grades, Triggers and Process
London has over 19,000 listed buildings. If you own one, any alteration affecting its character — internal or external — requires listed building consent, and unauthorised works carry criminal liability. This guide explains grades, what triggers consent, and how the application process integrates with planning.
Planning
Neighbour Objections and Planning: What Counts and What Doesn't
Objections from neighbours can sink a planning application — but only if they raise material planning considerations. Here's what councils weigh, what they discount, and how to handle objections constructively before and during the 21-day consultation.
Regulations
Building Control Inspections: Stages, Inspectors and Sign-Off
Every London residential build above the smallest works needs Building Regulations approval, and approval requires inspection at defined stages. This guide explains what gets inspected, when, who does it, and how the completion certificate is finally issued.
Regulations
Structural Engineer and Calculations: When You Need Them and What They Cost
Almost every London extension, loft conversion, and structural alteration requires structural calculations from a qualified engineer. Here's when they are mandatory, what the engineer produces, fee ranges, and how their work integrates with building control sign-off.
Regulations
Completion Certificates and Structural Warranties Explained
When the build finishes, the paperwork matters more than the photographs. Final Certificates, completion certificates, NHBC and Premier Guarantee warranties — here's what each one is, when you need it, and what happens at sale or remortgage if you don't have it.
Regulations
Fire Safety for London Residential Builds: Part B and Post-Grenfell Rules
Fire safety regulations have tightened significantly since the Grenfell Tower fire in 2017. For London homeowners undertaking loft conversions, extensions and refurbishments, here's what Part B of the Building Regulations requires in 2026, plus the post-Grenfell measures every project needs to consider.
Construction
Loft Conversions in London: The Complete 2026 Guide
Loft conversions are London's highest-ROI home extension, adding 10-25% to property value while creating an entire new floor without losing garden space. This 2026 guide covers every loft conversion type, current London costs (£30k-£160k), realistic timelines, planning rules, building regulations, borough-specific quirks, and the contractor due diligence that separates a smooth build from a six-month nightmare.
Cost guides & insights
Budgets and expert analysis.
Cost guide
Loft Conversion Cost in London 2026
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Cost guide
House Extension Cost in London 2026
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Cost guide
Kitchen Extension Cost in London 2026
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Cost guide
House Renovation Cost in London 2026
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Cost guide
Loft Conversion Cost North London 2026
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Cost guide
Loft Conversion Cost South London 2026
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Cost guide
Loft Conversion Cost East London 2026
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Cost guide
Loft Conversion Cost West London 2026
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Cost guide
House Extension Cost North London 2026
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Cost guide
House Extension Cost South London 2026
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Cost guide
House Extension Cost East London 2026
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Cost guide
House Extension Cost West London 2026
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Cost guide
Basement Conversion Cost in London 2026
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Cost guide
Garden Office Cost in London 2026
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Cost guide
Conservatory & Orangery Cost in London 2026
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Cost guide
Garage Conversion Cost in London 2026
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Cost guide
Landscaping Cost in London 2026
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