Office and industrial use classes explained: B1, B2, B8 and Class E

Every building has a lawful planning use, set by the Use Classes Order. The class decides what the building can be used for, and which changes need planning permission. For offices and industrial buildings the classes changed on 1 September 2020, and the old labels are still widely used, which causes confusion.

What happened to B1?

Class B1 no longer exists. Until 31 August 2020 it covered offices, research and development, and light industrial uses. From 1 September 2020 all three moved into the new Class E, as part of “commercial, business and service” uses:

• E(g)(i): offices to carry out any operational or administrative function;
• E(g)(ii): research and development;
• E(g)(iii): industrial processes that can be carried out in a residential area without harming its amenity, which is what used to be called light industrial.

Shops, cafés and restaurants, gyms, clinics, nurseries and similar uses are also in Class E.

B2: general industrial

B2 covers industrial processes that do not fall within E(g), typically heavier work whose noise, vibration, fumes or traffic would not suit a residential area. Workshops, vehicle repair, manufacturing and processing often fall here.

B8: storage or distribution

B8 covers warehouses, distribution and storage, including open-air storage. Many units on industrial estates are in B8, or in a mix of B2 and B8.

Which changes need planning permission?

• Within Class E, for example from light industrial to offices, or from an office to a clinic, a change of use generally does not need planning permission, because the use stays in the same class.
• From B2 to B8 is allowed without a planning application under permitted development, for up to 500 square metres of floor space.
• From B2 or B8 to offices or other Class E uses usually needs a planning application.
• From Class E to homes may be possible under the Class MA permitted development right, through a prior approval application rather than full planning permission. Our Class MA guide explains what it allows.

What to check before relying on it

• The lawful use. What the building is used for today is not always its lawful use. The planning history, and how long the current use has run, decide that.
• Conditions. A planning permission may have a condition limiting the use to one activity, or removing the freedom to change within a class.
• Article 4 directions. Councils can remove permitted development rights in particular areas.
• The lease or title. A user clause can restrict the use whatever planning allows.
• Building work. A change of use can be allowed while the works it needs, such as new windows or a mezzanine, still need permission and building regulations approval.

Where the position is unclear, a Lawful Development Certificate from the council gives certainty before you buy, let or convert.

In Kent, a buyer of three industrial units is weighing up occupying one, and selling, converting to offices or letting the others in their existing use. Read the case study, or see converting an industrial unit to offices.

Planning rules change, and this guide is general information rather than advice on a particular building. A planning consultant or the council can confirm what applies to yours.

For the wider options on an industrial site, from splitting into smaller units to redevelopment, see industrial sites: redevelop, convert or split?