Do you need planning permission for a mezzanine floor?

The general rule: internal works are not development

Planning permission is needed for “development”, and the Town and Country Planning Act 1990 says works that affect only the interior of a building are not development. A freestanding mezzanine built inside a warehouse, factory or office, with nothing changing outside, normally falls into that category. That is why installers and advisers such as Peninsula say a mezzanine usually does not need planning permission.

There are, however, several situations where planning does come in, and one of them catches a lot of retailers.

The 200 m² rule for shops in England

Large retailers used to add mezzanines to out-of-town stores to increase selling space without any planning control. To close that gap, the government made the Town and Country Planning (Mezzanine Floors) (England) Order 2006. Read with section 55(2A) of the 1990 Act, it makes internal works that increase the gross floor area of a building used for the retail sale of goods by more than 200 square metres count as development.

In plain terms:

• Shop or retail warehouse, mezzanine over 200 m²: planning permission needed.
• Shop, mezzanine of 200 m² or less: normally treated as internal works.
• Hot food outlets: excluded from the rule.
• Warehouses, factories, offices, gyms: the rule does not apply, because they are not used for the retail sale of goods.

If a trade counter or showroom also sells goods to the public, check with the council how it views the building’s use before assuming the rule does not apply.

Scotland and Wales

The 2006 Order covers England. Scotland and Wales have their own planning systems, and Scotland’s equivalent rules came through the Planning etc. (Scotland) Act 2006. Check with the local planning authority if your building is outside England.

Other times planning or consent may be needed

Even when the mezzanine itself is internal, other parts of the project can need permission:

• Changes outside: new windows, doors, roof lights, extraction flues or external stairs are development in their own right.
• Change of use: if the mezzanine is part of turning a warehouse into offices, a gym or a shop, the change of use may need permission. Peninsula lists change of use among the triggers.
• Listed buildings: listed building consent is needed for internal works that affect the building’s character, even when no planning permission is.
• Conditions on the existing permission: some industrial and retail permissions limit floor space or uses. Your original planning permission, or the council, will tell you.
• More traffic or parking: a floor that adds staff or customers can raise questions about parking and deliveries on some sites.

Who is the planning authority?

Usually the district, borough or city council. A few areas have a different authority: in west London, for example, the Old Oak and Park Royal Development Corporation is the planning authority for its 650 hectare area across parts of Ealing, Brent and Hammersmith and Fulham. Our London mezzanine page covers this.

Planning is not building regulations

This is where most confusion comes from. Even when no planning permission is needed, a mezzanine almost always needs building regulations approval, because it adds structure and changes how people escape in a fire. Logistics Matters puts it simply: mezzanines generally do not need planning approval, but they do need building regulations approval.

The application goes to the council’s building control team or a registered building control approver, with structural calculations and drawings, and the work is inspected before a completion certificate is issued. Our guide to mezzanine building regulations explains what they check.

Your landlord’s consent

If you lease the building, the lease probably needs the landlord’s written consent for alterations, and may say the mezzanine must be removed at the end of the term. This is not planning, but in practice it is often the first hurdle. Ask early, and show the landlord the installer’s drawings and the fact that the floor is freestanding.

A quick checklist

1. Is the building used for retail sale of goods, and will the floor add more than 200 m²? If so, apply for planning permission first.
2. Will anything change outside the building, or will the use of the building change?
3. Is the building listed, or is there a condition limiting floor space?
4. Has the landlord agreed in writing?
5. Who will apply for building regulations approval? Usually the installer.

What it means for cost and timing

Where planning is needed, allow time for the application before work starts; the installer can usually provide drawings for it. The mezzanine itself is priced the same either way. Our mezzanine floor cost calculator gives a range for your size and use, and our retail mezzanine page covers the extra requirements for shops.

This guide is general information, not legal advice. The council’s planning team can confirm what applies to your building, and our free service can put you in touch with a mezzanine floor installer who deals with these questions every week.