Start here · if you’re still deciding
Extend or move?
What it costs to build, set against what it costs to sell up and move — so the biggest decision runs on numbers, not feelings.
£49 · 24hr
See Extend or Move →
Build Cost Intelligence
Know the real number. Before you commit.
What your build, extension or renovation will really cost — itemised by trade, calibrated to your postcode, built on live UK cost data. Not estimates. Not averages.
Not sure which you need?
Answer three questions and land on the right report.
Find your report
Which report is for you?
Three questions. You’ll land on the one that answers your situation.
The reports
From a first decision to a tender-ready figure.
Five reports, one method. Each is built from your plans and priced for your postcode.
Compact · £199
“Should I even consider this?”
Full itemised cost schedule
Cost drivers across seven categories
Property intelligence — EPC, Land Registry, flood
The verdict — what the figure means
Renovation only. Extensions need Enhanced or Full Spectrum.
£19948hr · 10–12pp
See Compact →
Enhanced · £395
“Can I afford what I’m planning?”
Everything in Compact, plus:
Extension costs included
Summary scope of works
Headline programme
£39548hr · 15+pp
See Enhanced →
Full Spectrum · £975
“What will it cost — and how do I do it?”
Everything in Enhanced, plus:
Visual condition assessment from your photos
Full per-trade scope of works, tender-ready
Week-by-week programme
Decision schedule and risk register
£97548hr · 28+pp
See Full Spectrum →
Already have a quote?
Tender Intelligence · £199
“Is my builder’s quote realistic?”
Send the quote you have been given. Every line is benchmarked against live UK cost data, so you can see what is fair, what is high, and what has been left out — before you sign.
Line-by-line quote benchmark
A clear rating on every item
Missing items identified
Your true project cost
£19948hr · 8–10pp
See Tender Intelligence →
How the number is built
Real construction costs for your property.
Most figures for building work are averages — blended across regions, property types and specifications until they fit no single project. A BuildLens number is built the other way round: from your project, your plans and your postcode.
It is a desktop analysis, not a site visit. But every figure in it is constructed, not estimated.
Measured, not multiplied
Built from your plans
Every external and internal wall, the roof and every opening — existing and proposed — measured in full. Never floor area multiplied by a rate.
Priced this week
Calibrated to your postcode
Labour and materials priced from live UK trade and merchant data, updated continuously. A price in one area is never assumed to hold in another.
Itemised by trade
You see where it goes
Groundwork, structure, roofing, joinery, services, finishes — costed line by line, so the total is something you can interrogate, not just accept.
Held when it has to be
A figure that doesn’t guess
Where the drawings leave something that cannot be measured cleanly, the number is not invented. It pauses for a person.