Subdividing an office into serviced suites

Splitting an office floorplate into separately let suites usually needs no planning permission, because the use stays within Class E(g)(i) and internal works that do not affect the external appearance of the building are not development. The office subdivision planning units question that does matter is whether you are creating several separate planning units, and whether that changes the character of the use enough to be material. Most of the real risk sits in the conditions on the existing permission rather than in the use class.

Whether subdivision needs permission at all

Section 55 of the Town and Country Planning Act 1990 defines development as building, engineering, mining or other operations, or a material change of use. Works affecting only the interior of a building, or not materially affecting its external appearance, are excluded from the operations limb.

So partitioning a floor, adding doors, forming a reception and installing new services are not operational development in an unlisted building. The use class does not change either, since a serviced suite let to a small firm is still an office in Class E(g)(i), and movement within Class E is not development.

The statutory exception that catches people is in section 55(3)(a), and it applies to dwellinghouses rather than offices. Subdividing a single dwelling into two or more separate dwellings is expressly a material change of use. There is no equivalent provision for commercial floorspace.

The separate planning unit question

The planning unit is the area to be considered when asking whether a change of use has occurred, and the usual starting point is the unit of occupation. Subdivide a building into eight separately let suites and you may well have created eight planning units where there was one.

That is not itself a breach. The use of each unit remains an office, so there is no change of use. What the authority can look at is whether the overall character of the use has changed materially, and the triggers are physical rather than legal.

• A step change in the number of people on site, and therefore in trips, parking demand and waste.
• Shared facilities that introduce an element outside Class E, such as a public cafe or an events space open to non-tenants.
• External changes, including new entrance doors, signage, a cycle store, external plant or a smoking shelter.
• Servicing patterns, where eight tenants each take their own deliveries rather than one goods-in operation.

Where any of these apply, the sensible route is an application for a certificate of lawfulness for a proposed use or development under section 192 of the 1990 Act. It gives you a binding answer in eight weeks for a fee, and a lender or an incoming tenant will accept it where they will not accept your view of the law.

Conditions on the existing permission

This is where subdivision schemes actually come unstuck. Older office permissions frequently carry conditions that have nothing to do with use classes and everything to do with occupation.

Pull the full planning history before you draw a layout. A section 73 application to vary an occupancy condition takes eight weeks and is usually straightforward, but it is an application, and discovering the need for it after you have signed heads of terms with four tenants is an avoidable problem.

Shared facilities and common parts

Serviced suites normally come with a shared reception, meeting rooms, a kitchen or tea point, lockers and sometimes a staffed front desk. All of that sits comfortably within the office use as ancillary provision.

The line is crossed when a shared facility becomes a business in its own right serving people who are not occupiers of the building. A cafe open to the street, a gym selling memberships, or an events venue hired out at weekends are each a separate use that would need permission on its own terms. Our note on indoor golf and simulator venues in vacant retail works through how those secondary uses are assessed.

Keep the ancillary nature evident in the documents. A floor plan labelling the cafe as tenant amenity, with a lettings policy restricting use to occupiers and their visitors, is the kind of detail that settles the question before it is asked.

Parking, refuse, cycles and servicing

Parking is the most common objection on a subdivision that does need permission. A single-occupier building with 40 spaces allocated informally becomes eight tenancies each wanting a guaranteed allocation, and the arithmetic rarely works. Where the council raises parking demand, local parking standards apply per unit, and evidence from a Parking Survey of actual on-street stress is more persuasive than a theoretical calculation.

Refuse is the detail that generates most planning conditions. Eight tenants mean eight waste contracts unless you provide a managed store, and councils expect a store sized for the number of units, accessible for a collection vehicle within the usual drag distance, and screened. A Waste Management Strategy covering container numbers, collection frequency and the management arrangement answers it.

Cycle parking should be sized against the local standard for the total floorspace rather than per tenancy, with showers and lockers where the standard requires them. Servicing is worth a short note in the Transport Statement explaining how deliveries will be handled across multiple tenancies, because a single loading bay shared by eight firms is a condition waiting to be imposed.

Fire safety and means of escape

Subdivision is a building control matter before it is a planning one, and the Building Regulations drive the design. New compartmentation between suites, protected escape corridors, door hold-open devices, signage, emergency lighting and alarm interfaces all follow from creating separate tenancies, and Approved Document B is the reference.

Once occupied, the Regulatory Reform (Fire Safety) Order 2005 applies, and subdivision creates multiple responsible persons who have to co-operate. The practical consequence is a building-wide fire strategy, a shared alarm and evacuation arrangement, and a landlord's risk assessment that each tenant's own assessment plugs into.

Planning Gateway One does not apply here. It applies to relevant buildings containing dwellings, so an office subdivision does not trigger a planning stage fire statement, which is a frequent misunderstanding where the building is tall.

What to submit

If no permission is needed, submit nothing and consider a section 192 certificate for comfort. If a condition has to be varied, a section 73 application with a short covering statement and an updated layout is normally enough.

Where external alterations are proposed, or the council takes the view that the character of the use is changing, the application needs a Planning Statement setting out the use class position, the planning unit analysis and the conditions being addressed, with the transport, waste and cycle information appended. Keep it short. The officer's question is narrow and the submission should answer it directly.

This is general guidance, not legal advice, and the position should be checked with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.