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Enter a property
Search by postcode or address and resolve the exact property before anything else.
For London homeowners
Instant planning intelligence for any London property.
See planning constraints, build potential, and local precedent before you spend money on drawings or consultants.
33London boroughs
OfficialPlanning data
FreeTo get started
Sample Property Result
18 Example Street, SW18
This shows the kind of headline read the app produces once a property is resolved and a project has been assessed.
Top insights
- Rear extension likely to be a workable route.
- Conservation controls are nearby, so external appearance still matters.
- Three similar approvals sit within 100m of the site.
Development potential
Rear extensionLikely
Loft conversionPossible
Side returnPossible
Garden roomLikely
Planning score
78 / 100
Constraints found
2 signals
Nearby approvals
3 decisions
3 free checks · no credit card required
Looking for a specific property?
Covers all 33 London boroughs
Uses official planning data
Used by homeowners, developers, and architects
How It Works
From address to planning result
Resolves the property, identifies the planning authority, applies the right rules, and returns constraints, precedent, and a planning score.
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Analyse constraints
We combine local controls, mapped planning layers, and the right householder rules.
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Get an expert-style report
See the planning score, key risks, local precedent, and recommended next moves.
Coverage
All common London householder project types covered.
From rear extensions and loft conversions to garage conversions, front garden paving, and window replacements.
Extensions & conversions
Rear extensionSide extensionLoft conversionGarden roomGarage conversionBasement / cellarPorch
External & front works
Dropped kerb / drivewayFront garden pavingWindow replacement
Free Preview
See the score, constraints, and precedent before checkout.
The preview surfaces the same core outputs the application calculates for each property. Checkout unlocks the detailed report and PDF.
Constraint Intelligence
Conservation area, Article 4, flood risk, and listed building signals in one place.
Development Potential
A matrix view of likely opportunities, constrained routes, and planning friction.
Local Precedent
Nearby approvals and refusals that explain how the authority behaves around similar work.
Result Structure
Score, constraints, map, and precedent
Each result opens with the planning score, then moves through key insights, constraint summary, development potential, map layers, and nearby planning decisions.
Planning score
78
Good potential for extension
+ Local precedent
Current routeLikely permitted development
Key constraintConservation context nearby
ConfidenceStrong
Key insights
Rear extension likely permitted if massing stays controlled.
Strong approval precedent within the local authority area.
Article 4 not detected for this site.
Flood context exists nearby but does not dominate the read.
Development potential
Rear extension
Likely
Loft conversion
Possible
Side return
Possible
Garden room
Likely
Map-Based Intelligence
Constraint layers show why a site is straightforward, constrained, or risky.
The map mirrors the same inputs used in the result: conservation areas, flood zones, and Article 4 controls that can change whether a project stays within permitted development.
Conservation areas
Explain character controls and design sensitivity.
Flood zones
Show where buildability is likely to tighten.
Article 4 directions
Highlight where permitted development may be restricted.
FloodConservationArticle 4
Sample Site
Map Insights
- Rear boundary touches a mapped conservation area edge.
- Flood risk is present locally but not directly over the dwelling footprint.
- Article 4 control is likely to affect external appearance changes.
Why it matters
The user immediately sees where planning risk is coming from instead of decoding policy language alone.
Common Questions
Planning questions, straight answers
Do I need planning permission for a rear extension in London?
It depends on the scale of the extension, the property type, and local constraints such as conservation areas, listed status, Article 4 directions, and flood risk. Many householder projects can follow permitted development, but that route is highly site-specific.
What makes CanUBuild different from a basic planning checker?
CanUBuild combines address-level site matching, mapped constraints, permitted development logic, and nearby planning precedent into a single planning intelligence dashboard rather than a simple yes or no answer.
Can I still change the detected property type?
Yes. We infer the likely property type from the address when possible, but you can override it before the analysis runs so the assessment reflects the right planning rules.
What do I see before I pay for a full report?
You see the headline planning read, constraint summary, and report structure. Checkout unlocks the detailed constraint analysis, precedent records, map context, and PDF access for that property.
Ready To Analyse
Move from "Can I build?" to "What is the smartest route?"
Start with the property, confirm the build idea, and get a planning dashboard that feels closer to a consultant briefing than a simple checker.