Grey Belt Planning: How to Get Permission for Your Custom Home

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What is the Grey Belt?

The grey belt is a new planning category introduced into the National Planning Policy Framework (NPPF) in December 2024. Its main purpose is to encourage more house building. The grey belt sits within the green belt, but is treated more favourably.

In this article, we will explore how you can use the grey belt to get planning permission for your custom home build.

Examples of Grey Belt Land

Previously developed land, e.g. old farmyards, redundant petrol stations, and derelict buildings within the green belt boundary.

Greenfield but low contribution, land on the edge of settlements, parcels enclosed by roads or development, fields that serve little green belt function.

Why Grey Belt Matters for Custom Home Building

Before 2024, building a home in the green belt required either Very Special Circumstances (VSC) or Paragraph 84. In both cases, these were very high bars. You had to demonstrate that extraordinary factors clearly outweighed the harm to the green belt.

Grey belt is, therefore, a game changer. If your site qualifies, you no longer need VSC or Paragraph 84. Instead, the planning balance tips in your favour, from a presumption against development to a presumption for it.

Early data is also promising. As of August 2025, 55% of all residential grey belt applications have been approved. For major schemes of ten or more dwellings, the approval rate is 80%.

The Four Criteria for Approval

To get planning permission on the grey belt, a proposal must meet all four criteria set out in NPPF paragraph 155.

Criterion 1: The site is a grey belt. The land must be previously developed or must not strongly contribute to the green belt purposes.

Criterion 2: It would not fundamentally undermine the remaining green belt. Developing one small plot does not mean the wider green belt will be compromised. As such, the smaller the development, the more favourably it may be seen.

Criterion 3: Demonstrable unmet housing need. This one is very important. Housing need is typically evidenced by the council's failure to demonstrate a five-year housing land supply, or under-delivery against its Housing Delivery Test. Many councils in the Midlands, such as Warwickshire, Solihull, and Stratford-upon-Avon, currently have an undersupply of housing. In the case of Worcestershire, their housing target has been increased by as much as 85%. Any grey belt application in these areas will therefore be seen very favourably from the outset, as councils need to meet these higher housing targets.

Criterion 4: Sustainable location. The site must be reasonably accessible to services and amenities. For single dwellings on village-edge grey belt sites, appeal decisions have confirmed that modest walkability is sufficient; you do not need to be next to a bus stop. However, as with much of planning policy, these things are discretionary and subject to the interpretation of the planning officer or committee.

How to Go About a Grey Belt Application

There are two main routes to securing planning permission on the grey belt. The right option depends on how strong the grey belt case is and whether you need to de-risk the site.

Route A: Full Planning Application. This is the standard route, a single application that addresses both the grey belt principle and the design in full. This route is quicker and is appropriate where the site clearly falls within the grey belt, for example, if it has been previously developed.

Route B: Permission in Principle (PiP). Permission in Principle is a two-stage route that is particularly well suited to grey belt land. It separates the question of whether the site is acceptable for development in principle from the detailed design and technical work, which comes later at the Technical Details Consent (TDC) stage.

At the PiP stage, only three things are considered: location, land use (i.e. residential), and the amount of development (i.e. one dwelling). This means you can establish that a custom home can, in principle, be built on your grey belt site before spending any money on architect design work, site surveys, structural engineers, or detailed technical reports. Once PiP is granted, the development principle is settled.

When PiP makes most sense: the grey belt case is uncertain, and you want to test it before commissioning design work; or you are considering selling the land, a site with PiP attached is significantly more valuable.

When a full application makes more sense: the site clearly falls within the grey belt (e.g. a disused petrol station or obvious low contribution to green belt purposes), or you have already undertaken a pre-application and the feedback has been positive.

Conclusion

Grey belt is the most significant change to green belt planning policy in decades. For the first time, there is a clear and realistic route to building a custom home on land that was previously off-limits.

If you have a green belt plot, or you are looking at one, the first step is understanding whether your site qualifies. That starts with a desktop review of the local Green Belt Assessment, the council's housing supply position, and the site's relationship to nearby settlements. In many parts of the country where there are not enough homes under the housing supply criteria, these projects are seen more favourably.

If you would like to explore whether your site has grey belt potential, then you can use the link below to speak with me.