Office to flats under Class MA: an illustrative pack

The documents that decide a Class MA prior approval are narrower than most owners expect, and the ones that cause delay are rarely the planning drawings. Natural light in the deep middle of an office floorplate, noise from whatever still trades downstairs, and evidence that the building sat in Class E use for two full years are what the case officer actually tests. What follows is an illustrative walkthrough of a Class MA submission example, built from the way these applications are assessed rather than from any real site or decision.

The building and the two year use test

Take a 1980s three storey office over a ground floor retail unit, roughly 620 m² on the upper two floors, with a single stair core and a deep plan that leaves the centre of each floor more than 8 metres from any window. The owner wants eight flats on the first and second floors and intends to leave the shop alone.

Class MA of Part 3 of Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 permits a change from Class E (commercial, business and service) to Class C3 (dwellinghouses), subject to prior approval. The building has to have been in Class E, or a qualifying earlier use, for a continuous period of at least two years before the date of the application.

That is a documentary test, so it is answered with documents. The pack in this illustration carried a signed lease schedule for the two upper floors, business rates records naming the occupier, and a short statement of use history cross-referenced to both. Dated photographs of the floors in occupation were added for the months where the rates record was ambiguous.

The exclusions in MA.1 matter as much as the use test. Class MA does not apply where the building is listed or sits within the curtilage of a listed building, nor on a scheduled monument, a site of special scientific interest, a safety hazard area or a military explosives storage area, and the full list in MA.1 should be read in the current consolidated order rather than from memory. Article 4 directions remove the right in defined areas in a number of authorities, so the Article 4 register is the first thing to check.

Why the vacancy condition is no longer in the pack

Older guidance, and a good deal of still-published advice, says the building must have been vacant for a continuous period of at least three months before the application. That condition was removed from Class MA with effect from 5 March 2024 by the Town and Country Planning (General Permitted Development etc.) (England) (Amendment) Order 2024, which also removed the 1,500 m² cap on the floorspace that could change use.

So the illustrative pack contains no vacancy evidence at all. It does contain a line in the covering statement confirming the two year use position and the date the right is being relied on, because the version of the order in force when the application is made is the version that governs it.

Natural light in a deep plan floorplate

The provision of adequate natural light in all habitable rooms is one of the matters the authority may consider on a Class MA prior approval, and on a deep floorplate it is the one that bites. A room with no window at all will not pass. A bedroom borrowing light through a glazed partition from a living space is argued about and often lost.

The solution adopted in this illustration was to pull the plan apart rather than to defend it. Two flats were deleted from each floor so that every habitable room sat on an external wall, the centre of the floorplate became the circulation, store and plant zone, and a daylight calculation was submitted for the two least favourable rooms rather than for all of them. Six flats instead of eight. The scheme that gets approved is usually the one that gave something up early.

Dwellings created under Part 3 rights also have to meet the nationally described space standard, so the internal areas were set against it before the layout was fixed, not afterwards.

Noise from the commercial units below

Impacts of noise from commercial premises on the intended occupiers of the new dwellings is a prior approval matter, and it is assessed the other way round from a normal planning application. The question is whether the flats will be acceptable places to live, given what trades nearby.

With a retail unit below and a bar two doors along, the illustrative pack included a measurement survey covering a Friday and Saturday evening, internal target levels drawn from BS 8233:2014, and a glazing and ventilation specification that achieved them with windows closed. A Noise Impact Assessment framed this way is short. Measure, state the target, show the build-up that reaches it.

One practical point. If the ground floor unit has an extract flue up the rear elevation, deal with it in the same document, because a bedroom window a metre from a kitchen extract is a complaint waiting to happen and the officer will spot it on the elevations.

Contamination and flood screening

Contamination and flooding are both prior approval matters, and on a town centre office both are usually screened out quickly. A desk study covering the site history, the made ground likely under a 1980s slab and the absence of any sensitive pathway for occupiers of upper floor flats is normally enough, and a Land Contamination Phase 1 assessment is the right vehicle for it. Where the history shows a former industrial use, intrusive work follows, and that has to be done by a suitably qualified and experienced person in accordance with BS 10175.

Flood screening works the same way. Confirm the flood zone from the Flood Map for Planning, and where the building sits in Zone 2 or 3 produce a Flood Risk Assessment dealing with safe access, egress and the fact that the habitable accommodation is above ground floor level. A conversion with no ground floor residential use is a much easier case than a new build on the same plot. Where contamination turns up after consent, the position changes sharply, as a conversion where contamination was found mid-build shows.

The decision, the conditions and the clock

Prior approval applications under Part 3 run to a 56 day determination period under paragraph W, and the development has to be completed within three years of the prior approval date. Both dates belong in the programme from the start.

In this illustration the approval carried conditions requiring the glazing and ventilation specification to be built as submitted, the layout to accord with the approved plans, and completion within the three year window. Nothing exotic. The conditions on a Class MA approval tend to mirror the prior approval matters, which is a reason to answer each one in a separate, clearly headed section rather than burying them in a single statement.

Two things slowed the determination. The rates record gap took a fortnight to resolve with the billing authority, and the first noise survey was done on a wet Tuesday in February, which produced a background level nobody believed. Both were avoidable with a month's lead time.

Community Infrastructure Levy liability is worth checking separately with the authority, because the treatment of existing floorspace depends on whether the building has been in lawful use for a qualifying period before permission. That is a question for the charging authority and its current schedule, not for the prior approval.

This walkthrough is illustrative. It is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it.

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