Part 7 Class A: extending a shop or a Class E unit

Shop extension permitted development exists, and it is narrower than most occupiers expect. Class A of Part 7 of Schedule 2 to the GPDO 2015 allows the extension or alteration of a shop or a financial or professional services establishment, subject to a floorspace cap of 50 square metres or 25 per cent of the gross floor space of the original building, whichever is the lesser, plus a set of conditions about height, boundaries, parking and designated land.

Two warnings before you measure anything. The right is drafted by reference to shops and financial or professional services establishments, which were separate use classes before the Use Classes Order was recast in 2020 and now sit inside the broad Class E. The interaction between the recast classes and Part 7 has been amended since, so read the current text of the Order rather than a summary. And the cap is measured against the original building, which means the building as it stood on 1 July 1948 or as first built, not as it stands today.

Which uses the right applies to

Part 7 Class A is about retail and, historically, financial and professional services premises. It has never covered restaurants, drinking establishments, hot food takeaways, offices in general, industrial buildings or warehouses, each of which has its own class within Part 7 or no right at all.

Since September 2020, a unit that was a shop and a unit that was an office may both sit within Class E, and they may swap between those activities without planning permission. That does not mean they share the same permitted development rights for building work. Whether Part 7 Class A is available to a particular unit depends on how the Order defines the qualifying use, and the safe assumption for any Class E unit that is not trading as a shop is that the right may not be available.

Where the position is arguable, the answer is not to build and hope. A Lawful Development Certificate for proposed development under section 192 of the Town and Country Planning Act 1990 costs a fee, takes eight weeks and settles it. On a leasehold unit where the landlord will ask questions at reinstatement, that certificate is worth having anyway.

Floorspace and footprint limits

The floorspace cap is the limit that decides most schemes. Fifty square metres sounds generous until you compare it with 25 per cent of the original gross floor space, because for any building over 200 square metres the percentage figure is the smaller of the two and therefore the one that applies.

A worked illustration, clearly illustrative rather than a decided case. A parade unit with an original gross floor space of 120 square metres has an allowance of 30 square metres, because 25 per cent of 120 is less than 50. A small kiosk of 60 square metres has an allowance of 15 square metres. Only a building under 200 square metres gets anywhere near the 50 square metre figure, and only a building of exactly 200 square metres reaches it.

Gross floor space means internal floor area measured across all storeys, so a two-storey unit counts both floors in the base figure. Extensions built under earlier permissions or earlier permitted development do not reset the original building, and they do consume the allowance. On a parade where units have been extended piecemeal since the 1980s, the remaining allowance is often nil, and nobody notices until the certificate application is refused.

Height and boundary constraints

The Order attaches further limits that operate independently of the floorspace cap, and each one is capable of defeating a scheme that passes on area alone.

There is a height limit on the building as extended. There is a separation requirement in relation to the boundary of the curtilage of the premises. There is a further restriction where the extension would come close to land in residential use, which exists to protect the amenity of the flat or house behind the parade rather than the shop itself. And there is a bar where the development would reduce the space available for parking, turning or loading.

Read A.1 of Part 7 for the current figures rather than relying on any secondary account, including this one, because these limits have been amended more than once. Then measure on site rather than from the lease plan, since service yards and delivery bays are routinely drawn wider than they are.

The parking and turning restriction is the one that catches occupiers most often. A rear extension into the yard that takes the turning circle below what a delivery vehicle needs takes the whole scheme outside the right, however small the extension is.

Where the right is excluded

Class A is not available on article 2(3) designated land, which covers conservation areas, National Landscapes, National Parks, the Broads and World Heritage Sites. A shop in a conservation area high street therefore needs planning permission for any extension.

It is not available where the premises are a listed building or sit within the curtilage of one, and listed building consent would be needed separately in any event.

An Article 4 direction can remove the right for a defined area, and many councils have made directions covering town centres and shopping parades. Check the council's list of directions rather than assuming.

Permitted development rights can also be removed by condition on a previous planning permission. On a unit within a scheme built in the last thirty years, look at the original permission for the parade, because a condition withdrawing Part 7 rights is common on retail development approved alongside housing.

Servicing and parking consequences

Even where the right is available, the practical consequences deserve a check before work starts.

Losing service yard space changes how deliveries happen, and deliveries that move to the frontage generate complaints, obstruct the footway and can attract enforcement under highways legislation rather than planning. If the extension takes the yard, work out where the lorry goes first.

Refuse storage is the second issue. Extending over the bin store leaves waste on the pavement, which for a food business creates an odour and pest problem and for any business creates a licensing or environmental health conversation. Where cooking is involved, extending across the route of an extract duct means the duct has to move, and a Ventilation and Extraction Statement will be needed if a planning application follows.

Rateable value changes with floor area, and so does the service charge on a leasehold unit. Neither is a planning matter and both surprise occupiers.

When a full application is unavoidable

Assume you are applying for planning permission if any of the following is true: the unit is in a conservation area or another designated area, the building is listed or in the curtilage of one, an Article 4 direction or a condition has removed the right, the allowance has been used up by earlier extensions, the extension would eat into parking or turning space, or the unit is trading as something other than a shop.

A full application for a modest commercial extension is not a heavy exercise. The pack is usually existing and proposed plans and elevations, a site layout showing servicing and parking, and a short Planning Statement setting out the policy position on retail floorspace, amenity and highways. Where the parade sits near housing, add a note on hours, deliveries and plant noise before the environmental health officer asks for one.

Where several units in the same parade are considering work, a single application for the terrace is often better received than four separate ones, because it lets the officer assess the frontage as a whole.

This is general guidance, not legal advice; check the position 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. Enter your postcode on PlanScope to see which documents an application for your unit would need.