Class E(g): offices, research and light industry

Class E(g) has three limbs and one qualification that applies to all of them. The limbs are offices carrying on operational or administrative functions, research and development of products or processes, and industrial processes. The qualification is that the use must be one which can be carried out in any residential area without detriment to the amenity of that area.

That qualification is the whole test. It is not about what the building looks like or what estate it sits on. It asks whether the activity itself, wherever it happened to be located, would harm residential amenity. A precision engineering workshop running hand tools during office hours passes. The same floorspace with a spray booth and a compressor running at six in the morning does not, and that use is Class B2 general industry.

The three limbs and what each covers

E(g)(i) is offices used to carry on an operational or administrative function. That is a broad category taking in professional offices, back office functions, call centres and administrative headquarters. It does not include uses that were deliberately placed elsewhere in the Order, so a medical practice is E(e) and a bank branch open to visiting members of the public sits in E(c).

E(g)(ii) is research and development of products or processes. Laboratories, testing facilities and product development space fall here, subject to the amenity qualification. A laboratory handling hazardous substances or generating fume extraction that would trouble neighbours is outside the class, and may bring in a separate consenting regime altogether.

E(g)(iii) is industrial processes. This is the successor to what the industry called B1(c) light industry, and the amenity qualification is doing the same work it always did. Assembly, small scale manufacture, food preparation for wholesale, printing, joinery with dust extraction contained, and similar activities generally qualify.

Storage and distribution is not in Class E at all. B8 is a separate class, and a unit used mainly for warehousing has not become Class E because the occupier also assembles a few items.

Where light industry ends and B2 begins

There is no floorspace threshold, no machinery list and no decibel figure in the Order. The line is drawn by judgement on the activity, and the factors that decide it are consistent.

• Noise, including impact noise and low frequency plant noise
• Vibration transmitted through the structure or the ground
• Emissions to air, including fume, dust and odour
• Hours of operation, particularly night working
• Vehicle movements, especially heavy goods vehicles and early deliveries
• External storage and external processes

A useful working test is to imagine the operation on a plot surrounded by houses on three sides. If you would need to argue for mitigation, conditions and restricted hours to make it acceptable, the use is not one that can be carried out in a residential area without detriment to amenity, and you are looking at B2.

Councils increasingly ask for evidence rather than assertion on this point. A short process description listing every item of plant, its noise data, the hours it runs and the extraction arrangements settles the question far more efficiently than a statement that the use is light industrial.

Moving between the limbs

Because all three limbs sit inside Class E, movement between them is not development at all under section 55(2)(f) of the Town and Country Planning Act 1990. An office can become a laboratory and a laboratory can become a light industrial unit without a planning application.

The works are a different matter. Loading doors, roller shutters, external plant, extraction, a mezzanine that adds floorspace, external stores and any change to the elevations all need their own permission. So does a change of use into Class E from outside it, such as from B8 storage or from a sui generis use.

Two practical points follow. First, on an industrial estate the constraint is rarely the use class and almost always the estate's own restrictive covenants and the landlord's consent. Second, a building that has drifted from office to workshop use over the years may have done so lawfully, and the value of confirming that with a certificate under section 191 of the 1990 Act is high at the point of sale or refinancing.

Conditions that tie a building to office use

The commonest obstacle is a condition on an earlier permission. Business parks and mixed use schemes were routinely consented with conditions restricting units to office use, often to protect a highway assumption about trip generation or to hold employment floorspace in a particular form.

Those conditions survive the 2020 changes to the Use Classes Order and continue to have effect according to their terms, including where they refer to a use class that no longer exists. Read every decision notice on the site, not only the most recent one, and read the conditions on the original outline or masterplan permission where the unit sits within a larger scheme.

Varying such a condition means an application under section 73, determined on planning merits with consultation. The highway authority will usually be reconsulted, and a change from office to light industrial use can alter servicing and heavy goods vehicle assumptions enough to attract an objection. A short Transport Statement that compares trip generation and servicing between the existing and proposed use is normally what resolves it.

Employment land policy, which is the other constraint

Where the proposal moves floorspace out of employment use, or reduces the amount of employment floorspace, local plan policy on the protection of employment land applies. Many authorities require marketing evidence over a stated period before they will accept the loss.

Where the proposal is a residential conversion, the Class MA prior approval route from Class E to dwellinghouses is the mechanism, and the conditions attached to it have been amended, including the removal of the floorspace cap and the vacancy requirement. Check the current wording of Schedule 2 Part 3 Class MA and whether the council has made an Article 4 direction removing it, because many have on industrial estates and in town centres.

Where the council resists a change on employment grounds, an Employment Land Assessment setting out the local supply position, the condition of the building and the marketing history is the document that answers the policy.

The evidence a council will want

For a change into E(g) from outside the class, expect to submit a Planning Statement covering the use class analysis and the policy position, a process description, drawings showing servicing and parking, and where plant is involved a Noise Impact Assessment using BS 4142:2014+A1:2019 for the fixed plant and a separate treatment of any impact or intermittent noise.

For a movement inside Class E with associated works, the works application should still explain the use position clearly, because a case officer who does not understand why no change of use application accompanies the shutter door will ask.

And put the hours in writing. Where a use sits close to the boundary between light industry and general industry, offering a condition limiting hours and prohibiting external processes is usually cheaper than arguing about the classification.

This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified professional before relying on it.