10 things open planning data can tell you before you buy a property
What free government open data can reveal about a property in England before you make an offer, from flood risk and heritage designations to green belt and ecological constraints, and where the data runs out.
Checking a specific site?
Check a site free: your council, whether you are in a conservation area, and a basic flood check. The £9.99 site report covers everything else we can check.
Postcode, address or grid reference. England, Wales and Scotland. Free check, then the site report is £9.99, one-off.
Every question below can be answered from free official sources, and we link to them. To check several at once, check a site free shows your council, whether the site is in a conservation area, and a basic flood check, with no signup.
You would not buy a car without checking its history. The same logic applies to property, except that the history that matters most is often what the land is designated as, not what the building looks like.
Free government open data can tell you a surprising amount about a site before you arrange a viewing. Here are 10 things you can find out. This guide covers England. In Wales and Scotland the publishers and some of the terms differ.
1. Whether the property is in a conservation area
Conservation areas have stricter planning controls. Permitted development rights are reduced, so work that would normally be allowed, such as side extensions, cladding or demolition above certain sizes, may need a planning application. This is not necessarily bad, because conservation areas are often desirable places to live, but it affects what you can do.
Source: check a site free, planning.data.gov.uk or your council's website
2. Whether the building is listed
A listed building cannot be altered inside or out without listed building consent. That includes things as small as replacing windows or moving an internal wall. If you are buying a listed property with plans to renovate, you need to know before you commit.
Source: the £9.99 site report, or Historic England's National Heritage List
3. Whether the site is in a flood zone
Flood Zone 2 and Flood Zone 3 mean medium and high probability of flooding from rivers and the sea. This affects insurance, mortgage availability and any future development plans. Even if the property has never flooded, the zone matters for planning and finance. Our checker reads the Environment Agency's current Flood Map for Planning for England, and the Environment Agency's own map is the official view to compare it with.
Source: the Environment Agency's Flood Map for Planning, or check a site free for a basic flood check
4. Whether the land is green belt
Green belt status tightly limits what can be built. If you are buying with the intention of extending, building an outbuilding or developing the site, it is one of the most important things to check. The presumption is against development unless it fits an exception or very special circumstances apply.
Source: your council's local plan policies map, planning.data.gov.uk, or the £9.99 site report
5. Whether there are tree preservation orders
Protected trees on or next to the property can limit development, restrict garden work and create obligations. Removing a protected tree without consent can lead to an unlimited fine in the Crown Court. National TPO data is incomplete, so ask the council.
Source: your council's tree officer, or the £9.99 site report
6. Whether the site is near a SSSI
Sites of Special Scientific Interest are protected for their wildlife, geology or other natural features. Development near a SSSI may need an ecological assessment, and Natural England may be consulted. This can add time and cost to the planning process.
Source: Natural England's MAGIC map, or the £9.99 site report
7. Whether Article 4 directions apply
Article 4 directions remove specific permitted development rights in a defined area. Work that would normally need no application, such as converting a house to a small HMO or changing certain commercial uses, then needs a formal application. They are easy to miss if you do not check. England's Article 4 data depends on councils submitting it, so ask the council directly.
Source: your council's planning pages, planning.data.gov.uk, or the £9.99 site report
8. Whether the property is near a scheduled monument
Scheduled monuments are nationally important archaeological sites with the highest level of protection. Works that affect one, including ground works within the scheduled area, need scheduled monument consent from the Secretary of State, with Historic England's advice. This can affect gardens, boundaries and groundworks.
Source: Historic England's National Heritage List, or the £9.99 site report
9. Which local authority manages planning
This tells you which council will decide planning applications, which local plan policies apply and where to find the planning department. Near council boundaries the answer is not always obvious.
Source: check a site free shows the council that covers any searched location, or use GOV.UK's find your local council
10. Whether the area is a National Landscape (AONB)
Areas of Outstanding Natural Beauty are now branded National Landscapes. They have stricter planning policy, in the same group as National Parks: major development is only supported in exceptional circumstances, and even smaller schemes face higher design standards and closer scrutiny. Some permitted development rights are lost, including the larger home extension scheme.
Source: Natural England's MAGIC map, or the £9.99 site report
Do your homework before you make an offer
Most of this is available from free official sources. The question is whether you check before or after you have committed.
Your solicitor's local authority search (CON29) will cover much of this ground, but it is usually ordered after your offer is accepted and after you have agreed a price. By then, pulling out is expensive.
Check a site free before you book a viewing. The site report (£9.99, one-off) adds the detailed findings with the source for each, for everything we can check within 500 m of your pin, for 30 days. The report link never expires. See a sample report first if you like.
We show what we found, what came back clear, and where a source couldn't be checked. Some councils don't publish every dataset, so ask the council where it matters. Planning Constraints is a screening tool. It is not a CON29, an LLC1 or professional advice.
Check the site before your solicitor orders searches.
Searches are usually ordered after your offer is accepted. Check a site free first for your council, conservation area status and a basic flood check. The site report (£9.99, one-off) adds everything else we can check within 500 m of your pin, for 30 days.
We show what we found, what came back clear, and where a source couldn’t be checked. Some councils don’t publish every dataset, so ask the council where it matters. Planning Constraints is a screening tool, not an official local authority search or professional advice.