Self build planning permission and custom build housing

 

Self build planning permission follows the same basic planning system as other new housing, but self-build and custom-build homes also have their own statutory register and land-supply duties. The planning system is supposed to recognise this as a distinct source of housing demand rather than treating it as simply another label for a one-off house.

The August 2026 NPPF expressly requires plans to assess the needs of people wishing to commission or build their own homes, and HO5 expects plans to identify plots where there is an identified need. Separate duties under the Self-build and Custom Housebuilding Act 2015 require relevant authorities to maintain registers and, unless exempt, grant enough suitable development permissions to meet qualifying demand.

There is one particularly important 2026 change too: for new planning applications made on or after 6 August 2026, self-build and custom-build development is no longer automatically exempt from mandatory Biodiversity Net Gain.

 

 

What is self build and custom build?

 

The statutory concept covers homes built or commissioned by individuals, associations of individuals, or people working with a developer where the future occupier has a real role in the design and specification of the home.

You do not have to lay the bricks yourself. Many self-builders employ an architect, contractor and project manager. The important point is that the home is being built or commissioned for the individual to occupy rather than being an ordinary speculative house chosen only after completion.

 

The self-build register

 

Relevant authorities must keep and publicise a self-build and custom housebuilding register. The register records individuals and associations seeking a serviced plot in the authority area for their own project.

Authorities can use eligibility conditions and, in some circumstances, operate the register in two parts. The register is evidence of demand, but being on it does not give an individual a right to a particular council-owned plot or planning permission for chosen land.

 

The duty to grant sufficient permissions

 

The 2015 Act, as amended by the Housing and Planning Act 2016 and later legislation, requires relevant authorities to give enough suitable development permissions on serviced plots to meet qualifying demand on the register, unless an exemption applies.

That is a duty on the authority overall supply of suitable permissions. It is not a promise that every person on the register will be offered a plot matching an exact preferred village, budget or design.

 

How the August 2026 NPPF treats self build

 

Policy HO1 says housing evidence should assess the needs of people wishing to commission or build their own homes. HO5 then says plans should identify plots for self and custom build housing and community-led development where there is an identified need.

HO7 is also useful in decision-making because substantial weight should be given to the benefits of providing homes which contribute towards evidenced accommodation needs. A genuine shortfall in self-build provision can therefore be relevant evidence, although it does not override site-specific planning harm.

 

Do I still need ordinary planning permission?

 

Yes. Being a self-builder does not create a permitted development right for a new house. The proposal still has to be acceptable under the development plan and the current national decision-making policies.

Within settlements, policy S4 provides the current national starting point. Outside settlements, the proposal needs to fall within a route under S5, and a genuinely isolated home in the countryside has the more restrictive HO11 test. If the land is in the Green Belt, the Green Belt policies apply instead.

For rural one-off homes, see our guide to building outside a settlement boundary.

 

What is a serviced plot?

 

The legislation uses the term serviced plot of land. The 2016 Regulations allow a plot to count where the necessary access and utility requirements can be provided within the duration of the development permission. The services therefore do not necessarily have to be physically installed on the day the permission is granted.

 

Biodiversity Net Gain changed on 6 August 2026

 

This is an easy trap because older articles still say self-build is exempt from mandatory BNG. For new planning applications made on or after 6 August 2026, the specific self-build and custom-build exemption has been removed.

Another exemption may still apply to a particular development — for example the current exemption for qualifying sites no larger than 0.2 hectares — but self-build status by itself no longer answers the BNG question. See our Biodiversity Net Gain guide.

 

CIL and self build are separate

 

The Community Infrastructure Levy has its own self-build exemption process. That should not be confused with planning permission or the self-build register. A house can qualify as self-build for CIL purposes but still require planning permission and compliance with all other planning conditions.

See our guide to the CIL self-build exemption before work starts because the procedural requirements matter.

 

Before buying a self-build plot

 

• Check the development plan and settlement boundary
• Search the planning and enforcement history of the land
• Check whether the plot is allocated, permissioned or merely promoted through a land assessment
• Check access, drainage, ecology, flood risk, heritage and landscape constraints
• Do not assume register membership makes an unsuitable plot acceptable
• Check the post-6-August-2026 BNG position
• Check CIL separately and follow the exemption procedure before commencement

 

Relevant law, policy and guidance

 

• Self-build and Custom Housebuilding Act 2015
• Self-build and Custom Housebuilding Regulations 2016
• Planning Practice Guidance: self-build and custom housebuilding
• National Planning Policy Framework, August 2026 — particularly HO1, HO5 and HO7
• Government guidance on BNG exempt developments

 

Other Housing Sections

 

Self Build and Custom Build Page Updated: 30th August 2026