Conservation Area and Planning Constraints Checker

What this checker looks up, and where the data comes from

• Designations come from planning.data.gov.uk, the planning data service built by the Ministry of Housing, Communities and Local Government. It combines data from councils and national bodies, and its dataset pages carry the warning: "The data may be incomplete and not yet cover all of England." (planning.data.gov.uk, checked 26 Sep 2026)

• Conservation area records come partly from councils and partly from Historic England and other sources. The service says the dataset "should be treated as a work in progress, and is currently incomplete". Where your council has not supplied its own boundaries, the result says so. (planning.data.gov.uk, checked 26 Sep 2026)

• Article 4 directions, tree preservation orders and listed building outlines are supplied council by council, and not every council has published them. When yours hasn't, the result tells you that instead of reporting nothing found. (planning.data.gov.uk, checked 26 Sep 2026)

• Listed buildings are recorded as a point inside each building. The data "does not define the extent of the area affected by the listing", so the checker can show listed buildings near your postcode but can't say whether your own home is listed. (planning.data.gov.uk, checked 26 Sep 2026)

• Flood zones come from the Environment Agency's Flood Map for Planning, the service for finding out whether a planning application needs a flood risk assessment. (Environment Agency, checked 26 Sep 2026)

• Postcode locations come from postcodes.io, which places each postcode at a single centre point: "the mean location of all addresses in that postcode". (postcodes.io, checked 26 Sep 2026)

• Nearby decisions come from UK PlanIt, a free index that collects applications from council planning registers. PlanIt says that in about 9% of cases an application has no location at all, so those can't appear in a search by distance. (UK PlanIt, checked 26 Sep 2026)

What a conservation area or other protected land means for your home

• Conservation areas, Areas of Outstanding Natural Beauty (now called National Landscapes), the Broads, National Parks and World Heritage Sites are all on the legal list of "article 2(3) land", along with areas specified under section 41(3) of the Wildlife and Countryside Act 1981. The householder limits below apply on all of them. (legislation.gov.uk, as at 26 Sep 2026)

• On article 2(3) land you need planning permission to clad the outside of a house in stone, artificial stone, pebble dash, render, timber, plastic or tiles, to build any side extension, or to build a rear extension of more than one storey. (legislation.gov.uk, as at 26 Sep 2026)

• The larger single-storey rear extension allowance, up to 8 metres for a detached house or 6 metres for other houses, isn't available on article 2(3) land. (legislation.gov.uk, as at 26 Sep 2026)

• Roof extensions such as dormers aren't permitted development on article 2(3) land, so they need planning permission. (legislation.gov.uk, as at 26 Sep 2026)

• A shed, garden room or other outbuilding can't go between a side wall of the house and the boundary without planning permission (Class E, paragraph E.3). Use the outbuilding size checker to test a garden building against every rule. (legislation.gov.uk, as at 26 Sep 2026)

• In National Parks, the Broads, National Landscapes and World Heritage Sites, garden buildings, enclosures, pools and tanks more than 20 metres from any wall of the house can cover no more than 10 m² in total (paragraph E.2). This limit doesn't apply in conservation areas. (legislation.gov.uk, as at 26 Sep 2026)

• National Landscapes are "areas legally designated as areas of outstanding natural beauty", so the planning rules for Areas of Outstanding Natural Beauty apply to them. (MHCLG, 17 Aug 2026)

• In a conservation area, demolishing a building, or some gates, fences, walls or railings, can need extra consent. (Planning Portal, checked 26 Sep 2026)

• Trees in a conservation area are protected even without a Tree Preservation Order: you must give the council 6 weeks' notice before work such as cutting down or pruning, unless an exception applies. One exception covers trees 75 mm or less in diameter, measured over the bark 1.5 metres above the ground. (MHCLG, 6 Mar 2014)

Article 4 directions, listed buildings, trees, flood zones and green belt

• An Article 4 direction lets the council "withdraw specified permitted development rights across a defined area". It doesn't ban the work: it "only means that a particular development cannot be carried out under permitted development and therefore needs a planning application". Each direction lists the rights it removes, so read the direction itself. (MHCLG, 26 Jul 2023)

• If your home is listed, you need listed building consent to demolish any part of it, or to alter or extend it in a way that affects its character. Listing covers the whole building, inside and out, and can cover other structures in its curtilage. Doing the work without consent is a criminal offence. (MHCLG, 23 Jul 2019)

• No shed, garden room or other outbuilding within the curtilage of a listed building is permitted development (Class E, paragraph E.1(g)). (legislation.gov.uk, as at 26 Sep 2026)

• A Tree Preservation Order means you need the council's written consent before cutting down, topping, lopping, uprooting, wilfully damaging or wilfully destroying a protected tree, and the government's view is that cutting roots needs consent too. Consent is still needed when the tree work is necessary to carry out permitted development, such as an extension. (MHCLG, 6 Mar 2014)

• Green belt and Flood Zones 2 and 3 are not on the article 2(3) list, so they don't reduce householder permitted development rights. They matter when you need planning permission. (legislation.gov.uk, as at 26 Sep 2026)

• A planning application for any development in Flood Zone 2 or 3, however minor, should include a flood risk assessment. There is specific guidance for a minor extension, meaning one of no more than 250 m² of floor space, and for a simple, low-risk project such as a house extension you may be able to write the assessment yourself. (Environment Agency, 28 May 2026)

• In the green belt, national policy (GB7) accepts an extension or alteration that "will not result in a disproportionate increase in size compared to the original building". The original building is the one that existed on 1 July 1948, or as first built if later. (MHCLG, 17 Aug 2026)

• A World Heritage Site buffer zone isn't article 2(3) land, so it doesn't reduce permitted development rights. But national policy asks development that affects a World Heritage Site to pay particular regard to its significance, including the contribution made by its setting, "including any buffer zone". (MHCLG, 17 Aug 2026)

• Works that damage, demolish, remove, repair, alter or add to a scheduled monument need scheduled monument consent, which is separate from planning permission. Doing them without consent is an offence. (legislation.gov.uk, as at 26 Sep 2026)

• Registered parks and gardens count as designated heritage assets in national planning policy, alongside listed buildings, conservation areas, scheduled monuments and World Heritage Sites. (MHCLG, 17 Aug 2026)

Why a postcode result is not the final word

• A postcode covers several addresses but is placed at one centre point. postcodes.io notes that when a postcode straddles a boundary, "the entire postcode is assigned to the area where the centroid falls". That is why the checker flags designations that come close to the centre point: a boundary can run between your home and next door. (postcodes.io, checked 26 Sep 2026)

• To confirm a result for your exact address, check your council's own conservation area map or appraisal, or ask its planning team. The Planning Portal points people to the government's planning data map for England and says to contact the local planning authority if unsure. (Planning Portal, checked 26 Sep 2026)

• Permitted development rights can also be removed from a particular house "by means of a condition on a planning permission". No map shows this, so look your address up on the council's planning register and read the conditions on earlier permissions. (MHCLG, 26 Jul 2023)

• To check whether a particular building is listed, search Historic England's National Heritage List for England by address or name.

How to read the nearby planning decisions

• Councils must keep a public register of planning applications, and a register kept electronically can be published on the council's website. (legislation.gov.uk, as at 26 Sep 2026)

• The checker counts decided applications for home extensions and alterations near your postcode and tells you the distance and period the count covers. Each example links to the council's own record, where you can read the decision.

• The approval rate is approvals divided by approvals plus refusals. Withdrawn applications are left out. With only a handful of decisions, one refusal can move the rate a long way, so read the counts as well as the percentage.

• For comparison, councils in England granted 90% of householder applications in the year ending March 2026. (MHCLG, 19 Jun 2026)

• PlanIt collects its records from council websites and is run by one person on a "best efforts" basis, with "no guaranteed service standards". If a council's website changes or blocks collection, recent decisions from that council can be missing. A short list doesn't mean few applications were made nearby: the council's own register is the full record. (UK PlanIt, checked 26 Sep 2026)

• Nearby decisions can come from more than one council, and policies differ between councils, so check which council decided each example.

When the free check is not enough

• The checker reports what is published. It doesn't read the reasoning behind each decision, and it can't tell you how your council is likely to treat your particular project.

• A Planning Confidence Report does that work for your property: it finds the decisions most like your project, on your street and across your council, and explains why the refused ones were refused.

• If you think your project is permitted development, a lawful development certificate is the formal way to confirm it. Once a certificate is granted, the lawfulness of the proposed work is "conclusively presumed" unless something material changes before the work starts. (legislation.gov.uk, as at 26 Sep 2026)

• An application for a certificate for proposed work costs half the normal planning application fee. (Planning Portal, 1 Apr 2026)

Common questions

How do I find out if my house is in a conservation area?

Enter your postcode in the checker above to see what the national planning data holds for your postcode's centre point. That data is incomplete, so confirm with your council's own conservation area map or its planning team, especially if a boundary is close or your council hasn't published its own data.

What can't I do without planning permission in a conservation area?

You need planning permission for any side extension, a rear extension of more than one storey, cladding the outside in stone, artificial stone, pebble dash, render, timber, plastic or tiles, and roof extensions such as dormers. A garden building between the side wall of the house and the boundary needs permission too, and demolishing a building or some gates, fences, walls or railings can need consent.

Is an Article 4 direction the same as a conservation area?

No. A conservation area is an area of special architectural or historic interest. An Article 4 direction is a separate order that withdraws specified permitted development rights in a defined area, so that work needs a planning application. Each direction lists the rights it removes, so read the direction itself.

Can I cut down or prune a tree in a conservation area?

Usually only after giving the council 6 weeks' notice. Trees 75 mm or less in diameter, measured over the bark 1.5 metres above the ground, are exempt. If the tree has a Tree Preservation Order, you need the council's written consent instead.

Is a postcode check definitive?

No. A postcode covers several homes and the check uses its centre point, so a boundary can run between you and next door. The national data is also incomplete, so a blank result means the designation was not found in the published data. For certainty, check the council's own map, or apply for a lawful development certificate for your project.

How can I see planning applications near me?

Every council keeps a public register of planning applications, which it can publish online. This checker shows decided home extension and alteration applications near your postcode, taken from UK PlanIt, with a link to each council record. For comparison, councils in England granted 90% of householder applications in the year ending March 2026.

Does green belt or a flood zone stop me extending?

Neither reduces householder permitted development rights, because neither is article 2(3) land. They matter if you need planning permission. In the green belt, national policy accepts an extension that doesn't cause a disproportionate increase in size compared to the original building. In Flood Zone 2 or 3 a planning application should include a flood risk assessment, which for a simple house extension you may be able to write yourself.

What if my house is listed?

You need listed building consent to demolish it, or to alter or extend it in a way that affects its character, inside or out. No outbuilding within the curtilage of a listed building is permitted development. The checker can show listed buildings near your postcode but can't tell you whether your own home is one of them.

Sources