Do I need Building Regulation Approval?

It’s worthwhile working on the assumption that Building Regulation approval is required, which is obtained via the Local Development Control Department within the relevant Local Authority, for most works that involve alteration of a service or structural part of the building.

The guide below should be used for guidance purposes only and as things can change quickly, you should always refer to the Local Authority to check before undertaking any works or purchasing a property where works have been carried out.


Work requiring permission

  • The erection and/or extension of any type of building
  • The change of use of a building
  • Replacement windows and boilers
  • Loft conversions
  • Internal structural alterations
  • Installation or alteration of any controlled fitting e.g. bath, shower, boiler
  • Underpinning of foundations to a building
  • Electrical installation
  • Re-roofing and re-plastering a building

Self certified work

If your building work consists only of the installation of certain types of services or fittings (e.g. electrical installations in dwellings, heating, hot water, air-conditioning and ventilation, replacement windows, WCs, and showers) and you employ an installer registered with a relevant Competent Person Schemes as designated in the Building Regulations, that installer will be able to self-certify (new window) the work. Therefore, you will not need to involve a Building Control Service. However, this concession is strictly limited to the specific type of installations and does not cover any other type of building work.

The works themselves must meet the current relevant technical requirements in the Building Regulations and they must not make other fabric, services and fittings less compliant than they were before. For example, the provision of replacement double-glazing must not make compliance worse in relation to means of escape, air supply for combustion appliances and their flues and ventilation for health.

Exempt work

The Guidance Note on Exempt Buildings (PDF 244KB new window) is intended to provide you with information about conservatories, porches, domestic garages and other small extensions and buildings which are exempt from the requirements of the Building Regulations. Certain conditions apply to these exemptions and should always be checked.

Do I need permission to…

Replace windows?

All owners replacing windows need to obtain consent and the windows themselves will have to meet the requirements of the building regulations fully.

You have a choice, you can either:

  1. Use an installer registered under the Fenestration Self-Assessment (FENSA) scheme run by the Glass and Glazing Federation, in which case you do not need to make a Building Regulation application. Your installer should then ensure your windows comply with the regulations and will supply you with a certificate confirming this when the installation is complete. You will also be offered the option of taking an insurance-backed guarantee. Please ensure that your installer is properly registered under the scheme before placing an order. You can check this and find out more details of the scheme by visiting the FENSA website (new window) . or
  2. Make a Building Regulation application to Flintshire Building Control; in most cases the simplest way of doing this will be to submit a Building Notice . You should complete a Building Notice form and return it together with the appropriate fee at least two working days before removing the old window(s). A Building Control Surveyor will call at your property to check the installation of the new windows. You are likely to be asked by your solicitor to produce evidence of this approval if you sell your property.

Erect a conservatory?

Generally you will not need building regulations consent to erect a conservatory. However, certain criteria must be complied with for your conservatory to be exempt. See exempt work (above)

Erect a porch? 

Generally you will not need building regulations consent to erect a porch. However, certain criteria must be complied with for your porch to be exempt. See exempt work (above)

Convert my loft?

Yes, we recommend that you use the Full Plans procedure to submit your application as great care has to be taken with loft conversions.

Build a detached garage?

Yes in some situations. See exempt work (above)

Build a garage extension to a house, shop or office?

Yes however, a car port extension built at ground level, open on at least two sides and less than 30m2 in floor area, is exempt. See exempt work (above)

Extend my house?

Yes, however, a porch or conservatory built at ground level and less than 30m2 in floor area is exempt provided that the glazing complies with the safety glazing requirements of the Building Regulations (Part N) (new window). See exempt work (above)

Carry out internal alterations?

Yes, if the alterations are to the structure, such as the removal or part removal of a load bearing wall, joist, beam or chimney breast.  You also need approval if, in altering a house, work is necessary to the drainage system or to maintain the means of escape in case of fire.

Repair my property?

Yes, if the repair work is major in nature e.g. removing a substantial part of a wall and rebuilding it, underpinning a building or re-plastering or re-roofing a building.

No, if the repairs are of a minor nature e.g. replacing the felt to a flat roof, re-pointing brickwork, or replacing floorboards.

Change the use of a building e.g. convert a house into flats? 

Yes, in the majority of cases, even where construction work is not intended. This is because the change of use may result in the building as a whole no longer complying with the requirements which will apply to its new type of use e.g. regarding fire safety etc. Please contact Building Control on 01352 703418 for advice.

Install fittings and appliances within my property?falling down house image

For example…

  1. a) Install or alter the position of a WC, bath, etc:
  • No, unless the work involves new or an extension of drainage or plumbing.
  1. b) Install or alter the position of a heating appliance?
  • Gas: Yes, unless an approved installer under the Gas Safety (Installation and Use) Regulations 1984 supervises the work.
  • Solid fuel: Yes,
  • Oil: Yes, unless an approved installer under the HETAS (the official body recognised by government to approve solid fuel domestic heating appliances, fuels and services)
  1. c) Alter in any way the construction of fireplaces, hearths or flues?
  • Yes.
  1. d) Install hot water storage?
  • Yes if the water heater is unvented (i.e. supplied directly from the mains without an open-expansion tank and with no vent pipe) and has storage capacity greater than 15 litres. A trained person must install such systems.

Carry out electrical works?

Yes. New safety regulations came into effect on 1 January 2005. From then electrical installations in dwellings became a “controlled service” under the Building Regulations.

Part P – Electrical Safety (new window), requires fixed electrical installations in residences to be suitably designed, installed, inspected and tested for safety. Also sufficient safety information will be available to people wishing to operate, maintain or alter an electrical installation.

Part P applies to electrical installations in:

  • Dwellings
  • Combined dwellings and business premises having a common supply (e.g. shops)
  • Common access areas and shared facilities in blocks of flats (e.g. laundry rooms but not lifts)
  • Outbuildings such as sheds, detached garages and greenhouses
  • External installations associated with buildings (e.g. fixed lighting and pond pumps)

Compliance with Part P can be achieved through one of the following options:

  • Use an electrician/installer who is registered with a Competent Persons scheme.
  • Submitting a Building Regulation application to the Council.

Insert insulation into a cavity wall?


Demolish a building?

Yes, you will need to notify the Building Control Service if you intend to demolish a building or part of a building if it has an external volume greater than 50 cubic metres. No fee is required. It’s strongly recommended that you contact the Planning Department to check if Planning Permission is required.

You can find out more detailed information by visiting the Planning Portal at and/or in the attached document here.  CLICK HERE