Laboratories and whether they sit within Class E
A lab is Class E(g)(ii) research and development only if it could be carried out in a residential area without detriment to amenity. Containment level is what tests that.
A laboratory in England falls within Class E(g)(ii) of the Use Classes Order, research and development of products or processes, but only if it clears the condition that sits across the whole of Class E(g): the use must be one that can be carried out in any residential area without detriment to the amenity of that area. A write-up laboratory with benches, fume cupboards and a modest extract passes that test easily. A containment level 3 facility with sealed ventilation, effluent treatment, bulk gas storage and standby generation does not obviously pass it at all.
That matters more than it used to. The former Class B1 was abolished when the Use Classes Order was amended in 2020, so a research use that fails the amenity condition no longer falls into a light industrial class. It falls outside Class E altogether, which in most cases makes it sui generis and requires a planning application for any change into it.
How research and development is classified
Class E(g) has three limbs, and the amenity condition applies to all of them.
| Limb | Covers |
|---|---|
| E(g)(i) | Offices, other than those in Class E(c)(iii) providing services principally to visiting members of the public |
| E(g)(ii) | Research and development of products or processes |
| E(g)(iii) | Any industrial process |
So an office building converting to laboratory use moves from E(g)(i) to E(g)(ii), which is a change within Class E and therefore not development at all. That is the legal basis for the lab-enabled office conversions that dominate the life sciences market in Cambridge, Oxford and parts of London.
Two familiar caveats apply. A condition on the original permission may restrict the premises to office use, which removes the flexibility, and our note on conditions that remove Class E flexibility explains how that works in practice. An Article 4 direction can withdraw permitted change rights in a defined area, covered in Article 4 directions that restrict changes of use.
The third caveat is the one people miss. Even where the use change needs no permission, the physical works usually do. Plant at roof level, a new riser enclosure, gas cylinder stores, condensers and a bin store for clinical waste are all development, and they are where the application actually lands.
Where a laboratory remains within Class E
Ask the amenity question about the finished operation rather than the label on the door. Four factors decide it.
- External plant: the size, position and acoustic performance of air handling, chillers, generators and extract discharge.
- Emissions to air: fume cupboard discharge, its height and its content.
- Deliveries and waste: vehicle types, frequency, and whether clinical or chemical waste is collected.
- Hours: continuous ventilation and out of hours working are common in research buildings.
A building whose plant is screened, whose extract discharges above the roof, whose deliveries are within normal working hours and whose waste is handled in a contained store is a straightforward E(g)(ii) case. Say so in the application, with the plant schedule attached, rather than asserting the class and moving on.
Containment levels and the point of departure
Biological containment levels 1 to 4 are defined for work with biological agents under health and safety legislation, and they are the clearest indicator of where a laboratory stops being a quiet neighbour.
Containment level 1 and most level 2 work sits comfortably inside Class E(g)(ii). The building looks like an office with more plant, and the amenity effects are those of any well serviced commercial building.
Containment level 3 changes the picture. Sealed rooms, directional airflow, HEPA filtration on extract, autoclaves within the suite, effluent treatment and resilient power all add plant, noise and servicing. Whether such a facility can be carried out in a residential area without detriment to amenity is a genuine question rather than a formality, and the honest answer is that it depends on the building and the neighbours. Containment level 4 work is confined to a very small number of national facilities and is not a planning question most readers will face.
The practical consequence is a strategy decision. Where a scheme is intended to accommodate level 3 space, treat the use as requiring permission and apply for it, describing the containment level and the plant. A permission granted for the operation you actually intend is worth far more than an argument about class that has to be run again when a tenant fits out.
Plant, extraction and gas storage
This is where applications are won or lost, so give it the detail it needs.
- A plant schedule listing every item, its location, its sound power level and the manufacturer's data.
- A roof plan and elevations showing screening, with the screen height dimensioned.
- Extract discharge heights and locations, clear of intakes and of neighbouring windows.
- Gas cylinder and bulk gas storage positions, with separation distances and bunding where relevant.
- Standby generator position, fuel storage, and the testing regime with proposed hours.
- Waste storage, separated by stream, including clinical and chemical waste.
A Noise Impact Assessment using the BS 4142 method is normally expected where residential property is nearby, and generator testing needs assessing separately because it is a short, loud, infrequent event rather than a continuous one.
Where quantities of hazardous substances exceed the controlled thresholds, hazardous substances consent is a separate regime from planning permission and has to be applied for in its own right. Check the quantities against the current thresholds early, because retrofitting a consent around an occupied building is difficult.
Employment land policy treatment
Laboratory floorspace is employment floorspace, and that cuts both ways in policy terms.
Local plans protecting employment sites will generally support a lab use on an allocated employment site, and may resist its loss to residential. An Employment Land Assessment is the evidence that shows how a proposal sits against the authority's employment land supply, and it is worth commissioning where the site is allocated or safeguarded.
Conversely, authorities in the main research clusters have used Article 4 directions to prevent office and light industrial floorspace being lost to residential under the permitted change routes. Where a scheme depends on that protection, say so, because an authority defending its employment land will treat a lab proposal more sympathetically than a speculative office refurbishment.
Floor to ceiling heights, floor loadings, riser capacity and plant zones are what make a building lab-capable, and they belong in the Planning Statement as justification for the massing rather than being left as an engineering matter.
Conditions on hazardous materials
Councils reach for conditions on lab schemes, and it is better to shape them than to receive them.
Sensible items to accept are plant noise limits at named facades, retention of screening, approval of a generator testing regime, and a requirement that waste is stored in the approved location. Be careful with conditions that fix a containment level, because a condition limiting the building to level 2 work will constrain future tenants and needs a section 73 application to vary.
Conditions requiring approval of details already shown on the submitted drawings are worth resisting. They add discharge applications and fees for no benefit.
Evidence to submit
For a change within Class E needing no permission, keep a file rather than making an application: the existing lawful use with evidence, the relevant decision notice and conditions, a note on Article 4, and a description of the intended operation. Where the position is arguable, a Lawful Development Certificate under section 192 of the Town and Country Planning Act 1990 settles it formally, and the route to establishing what the existing use is sits in proving an existing lawful use.
For a scheme needing permission, submit the plant schedule, roof plans and elevations, the noise assessment, an extract and discharge strategy, a waste strategy by stream, a transport note covering deliveries and staff travel, and a statement setting out the use class analysis and the containment level intended.
This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it, and remember that a Lawful Development Certificate is the only formal way to confirm that a use is lawful. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
Is a laboratory Class E?
Usually yes, within Class E(g)(ii) as research and development of products or processes, but only where the use could be carried out in a residential area without detriment to amenity. That condition applies across the whole of Class E(g). A facility with heavy plant, sealed ventilation and effluent treatment may fail it, in which case the use falls outside Class E.
Can an office be converted to a laboratory without planning permission?
The change of use itself is normally not development, because offices are Class E(g)(i) and research is Class E(g)(ii), and movement within Class E is not development. The physical works usually do need permission: roof plant, risers, extract discharge, gas stores and waste enclosures are all development. Check for restrictive conditions and Article 4 directions too.
What happened to Class B1 for research and development?
Class B1 was abolished when the Use Classes Order was amended in 2020, with its content absorbed into Class E(g). The practical consequence is that a research or industrial use failing the residential amenity condition in E(g) no longer has a light industrial class to fall into, so it is generally sui generis and needs planning permission.
Does a containment level 3 laboratory need planning permission?
Often, yes. Sealed rooms, directional airflow, HEPA filtered extract, autoclaves, effluent treatment and resilient power add plant, noise and servicing that make the residential amenity condition in Class E(g) genuinely arguable. Where a scheme is intended to accommodate that work, applying for permission and describing the containment level is more secure than relying on the class.
What evidence should a laboratory application include?
A plant schedule with sound power levels, roof plans and elevations showing dimensioned screening, extract discharge heights and locations, gas storage positions with separation distances, the generator testing regime, waste storage by stream, a BS 4142 noise assessment, a delivery and staff travel note, and a statement of the use class position and containment level.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.