Guides
Data-backed reference content for UK design-build firms, QSs, contractors and flood and drainage consultants: construction cost benchmarks pulled live from public data, and planning intelligence from the decision notices we read.
Planning intelligence
- Reference4 min read
The practices behind basement work, by London borough: how concentrated it is
How many architecture practices generate the basement applications in each London borough, and what share of that work the five and ten most active hold. Counts only; nobody is named.
- Reference4 min read
Basement planning conditions by London borough: drainage, SuDS and the start date
How often a basement approval carries a drainage or SuDS condition in each London borough, how often that condition must be discharged before work starts, and what it asks for.
- Reference5 min read
What a basement impact assessment condition requires
The three stages of a basement impact assessment, what the condition attached at approval asks for before work starts, and how often a drainage condition arrives on the same notice.
- Reference4 min read
Drainage and SuDS planning conditions by London borough: which councils condition most
Every London borough we have read deeply, ranked by how often an approval carries a drainage or SuDS condition, with pre-commencement share, discharge outcomes and the number of notices behind each row.
- Market analysis10 min read
Enfield SuDS requirements: drainage strategy checklist
A practical list of the plans, calculations and forms Enfield asks for, with evidence from recent planning conditions.
- Market analysis10 min read
Kensington and Chelsea SuDS requirements for basements
When RBKC expects a drainage statement, what the drawings must show, and the extra detail needed for basement schemes.
- Market analysis10 min read
Wandsworth drainage strategy and SuDS requirements
When a drainage design is needed, which runoff target to use and what Wandsworth planning conditions tend to ask for.
- Market analysis10 min read
Richmond SuDS requirements and drainage proforma
How to complete Richmond’s SuDS submission, from the London proforma and runoff target to maintenance and exceedance.
- Market analysis10 min read
Croydon drainage strategy and SuDS requirements
When Croydon expects a drainage strategy, which forms to use and what the calculations and drawings need to cover.
- Market analysis6 min read
Why drainage and SuDS conditions get refused
The refusal grounds we see most often on London decision notices, and what to submit instead.
- Market analysis5 min read
Pre-commencement drainage conditions: what they hold up
How often a drainage condition has to be discharged before you can break ground, and what that costs in programme.
- Reference5 min read
What does a SuDS planning condition actually require?
The recurring themes in drainage conditions on London approvals, and why the obligation does not end at design.
- Market analysis5 min read
London SuDS and drainage planning conditions: what the decision notices show
What London drainage and SuDS conditions actually ask for, how often discharge submissions fail, and how the burden varies by borough, from the decision notices we read every morning.
Construction costs
- Sales6 min read
Which jobs to quote this month: a bid or no-bid triage for small building firms
Six questions, a scorer, and three verdicts for every enquiry: price it, ask one question first, or decline it this week.
- Reference5 min read
How much does BCIS cost, and what do you get for it?
What a BCIS subscription runs to, what sits behind the paywall, and what the free sources cover instead.
- Reference5 min read
Is BCIS worth it for a small practice?
A decision rule for one-QS firms: when the subscription pays back, and when the free stack covers you.
- Market analysis6 min read
UK construction cost forecast 2026: where costs are heading and why
What the leading indicators say about the next 12 to 18 months of UK construction cost inflation.
- Sales5 min read
How to justify a construction quote increase to a hesitant client
The live-data scripts and worked examples to have an evidence-based conversation about why 2026 numbers are higher than 2022 numbers.
- Sales6 min read
Fixed price vs cost plus contracts in UK construction 2026
What current labour inflation means for how you price, contract, and manage risk on residential projects.
- Reference4 min read
UK construction cost index, 2026: live figures and what's moved
The latest ONS and DBT construction cost indices, auto-refreshed on publication. Plus what changed this quarter and why.
- Reference7 min read
JCT fluctuation clause calculation: worked example with current indices
How JCT Option A, B and C fluctuation clauses work, with a live calculator for the bespoke index-linked approach on the free ONS and DBT series.
- Market analysis6 min read
Why UK construction labour keeps getting more expensive in 2026
The Apprenticeship Levy, CITB levy, employer NI changes, and the structural labour supply shock, explained through the ONS labour cost index.
- Reference6 min read
Part L 2025 cost impact on UK residential new build and extensions
What the 2025 Part L amendments add to build costs, by project type and spec, with a live index-adjusted benchmark.
- Market analysis6 min read
Building Safety Act Gateway 2 cost impact on residential HRBs, 2026
What design, programme and construction cost lines the Gateway 2 approval regime is adding to residential higher-risk buildings.
- Market analysis5 min read
UK construction cost inflation in 2026: what design-build firms need to know
The latest ONS data, the labour / materials divergence, and what it means for your pricing.
- Reference6 min read
Cost per m² benchmarks for UK residential extensions, Q3 2026
Live-adjusted reference rates for rear extensions, loft conversions and basement digs, by region and spec tier.
- Reference5 min read
BCIS alternatives: free UK construction cost data for small practices
What the free sources cover, where they fall short, and how to stitch them together.
- Market analysis6 min read
UK labour vs materials: the divergence reshaping residential pricing
Why labour costs keep rising while materials have stabilised, and what it means for your quotes.
- Reference5 min read
Regional cost factors across the UK in 2026
Live regional premiums for construction costs: London vs rest of UK, with worked examples.
- Reference6 min read
UK tender price index explained: TPI vs COPI vs building cost index
What each index actually measures, which one to use when, and how to apply it to your cost plan.
- Reference5 min read
UK trades day rates in 2026: bricklayers, electricians, carpenters and more
Live-adjusted day rates for qualified UK tradespeople, with regional variation.
Can't find what you need?
The construction-cost guides are built on the same data that powers the Trails Cost Tracker. For the interactive calculator, inflation adjustments and regional variations, use the tool directly. The planning-intelligence guides come from the decision notices we read across London, and are refreshed daily.
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