Building Regulations: when do you need to notify building control about home improvements?

By law, all new building constructions and many alterations to existing buildings must conform to building regulations. We look at when you need to notify building control about your home improvements.

In this article

Building regulations are legal minimum standards for the design, construction and alteration of buildings. They cover areas such as the size and dimension of rooms, the quality of materials you can use, fire-safety measures, ensuring adequate access, ventilation and so on.

An extension or alteration to your property, plus any new building, will need to comply with building regulations in England or Wales. You or your builder will need sign-off from building control at the end of the project to certify that it reaches the minimum standards specified by the regulations. If you’re planning a loft conversion, check the Which? guide to loft conversions for more detailed advice and ideas.

Building regulations versus planning permission

You may need both planning permission and building regulations approval on a construction project. They are not the same thing, although both are typically managed by your local council.

Building control departments measure compliance with the regulations around specific safety and material standards for construction projects. You can find your local authority's building control department through your council website, which should give more information about charges and who to contact. You can also use an approved private Building Control company that can sign-off your work in the same way as your local council.

Planning departments are concerned with the nature of a development, whether it’s appropriate for the site in question, and if it fits in with the existing neighbourhood. Check our guide on planning permission to find out whether you need to contact your planning department for your project.

When do you contact building control?

Notifiable work

Any new construction or extension of a building counts as ‘notifiable’ work. This means you must let the local council building-control department or a privately run building control service know about it, so it can inspect and certify the work on completion.

You also need building-regulations approval for some home alterations, including:


  • replacing fuse boxes and connected electrics
  • changing electrics near a bath or shower
  • adding new circuits

Glazing / ventilation:

  • replacing windows and doors
  • putting in a fixed air-conditioning system

General building:

  • underpinning a building’s foundations
  • any new extension
  • insertion of insulation into a cavity wall
  • work affecting the energy performance, thermal elements or energy status


  • replacing roof coverings on pitched and flat roofs


  • installing or replacing a heating system
  • adding extra radiators to a heating system


  • installing a bathroom that will involves changing the plumbing (ie when toilets, sinks and so on are in different places – like-for-like sanitary ware replacement doesn’t require approval).

Other repairs, replacements and general maintenance work will not need building-regulations approval. If you are in any doubt, check with your trader. All Which? Trusted traders will operate in line with the current regulations, and will know which jobs need approval.

Methods of notification

Full plans

A full-plans notification means you send in full details of the construction project, including plans and architectural drawings, to your local authority building-control service, at least five weeks before work is due to start. It will consult with the necessary authorities (such as sewerage) and will issue you with a decision within five weeks.

Your local authority may approve your plans, ask for further information or amendments, provide a conditional approval (where it adds specific conditions) or refuse the plans. Provided you receive approval, you can go ahead, and your local authority will carry out inspections of the building work while it’s in progress.

Building notice

A building notice is best suited to smaller projects. It’s a less-detailed application than full plans, and doesn’t need to be accompanied by plans or drawings. A building notice is a good idea if you are confident your project will comply with building regulations.

Once you’ve given your building notice, you need to inform your local authority when you start work, and then it will carry out site inspections during the work.

You cannot use a building notice where:

  • the work will take place close to or over rain or foul-water drains
  • a new building fronts on to a private street
  • buildings are covered by the 2005 Fire Safety order (most commercial buildings).

Self-certification and the competent-person scheme

You are ultimately responsible for ensuring that any works on your property comply with building regulations (and planning laws if necessary). If works aren’t in line with regulations, it will be you who is served with an enforcement notice and responsible for putting it right.

However, if you employ a trader, the responsibility for dealing with building control normally passes to them. It’s always worth checking who will carry out any notifications with your trader at the start of a project.

Traders that are part of a competent-person scheme, such as Fensa for glazing, NAPIT, Certsure (trading as NICEIC or ELECSA) for electricians, or the Gas Safe Register, are able to certify their own work. Before a trader can register on a competent person scheme, they need to pass a relevant skill test to ensure they are still operating at the required standard.

If your trader is part of a competent-person scheme, you won’t need to worry about reporting work separately to building control. The trader will take care of any notification and certification, without the need for a separate visit from building control. You will save time and money, too, as you won’t pay the related charges associated with applications for approval.

All Which? Trusted traders undertaking notifiable building work will be part of their relevant competent-person scheme. If you want to find a trader you can trust, Which? Trusted Traders has endorsed businesses in your local area.

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