Building Regulations: Dwellinghouse & Extensions

by Andrew P Bonell

There has been much talk in the legal press recently about building regulations and when, if at all, they are needed. The following constitutes a very short guide, which might help if you are thinking about doing work on a property.

If you want to put up a new building, extend or alter an existing one, or provide fittings in a building (such as drains or heat producing appliances, washing and sanitary facilities, and hot water storage), then building regulations will probably apply.

They may also involve certain changes of use to the existing building even though construction work is not intended: for example, the conversion of an integral garage to a bedroom. The attic converted to a ‘playroom’ or a useful storage area will become a ‘liveable’ space if used as a normal part of the house and will therefore, require building regulations. The basement converted to a home gym will also require building regulations. The test is factual. Is the room now being used as a normal part of the house?

There are exemptions for porches or conservatories built at ground level or a single storey garage or carport not exceeding 31 square metres in floor area. A conservatory measuring 15’ x 18’ would be exempt.

Over recent years, building regulations have been extended. They now cover other works to property which, if undertaken wrongly or negligently, or by persons who are not properly qualified, could result in damage to the property or indeed the persons within it.

 Accordingly, there are now requirements for safety glazing. Since 1stApril 2002, any new or replacement glazing (doors, windows, roof lights or roof windows) requires either a FENSA Certificate (from any installer registered with a ‘Competent Person Scheme’) or a Building Control Certificate.

Competent Person Scheme

Web address


FENSA (Fenestration Self Assessment Scheme)

0870 780 202

British Standards Institution (BSI)

01442 278 607


01292 266 636

From 1st March 2003, a new central heating boiler will have needed a certificate of installation by the contractor, or a Building Control Certificate.

Since 1st January 2005, it has been a requirement that certain electrical wiring installed or added to since that date must carry a certificate from a competent electrician that it has been done in accordance with current standards.  Exemptions apply to wiring or extract sockets in a dwelling as long as they are not to wet rooms e.g. bathrooms and kitchens; nor any outside works. 

The following are examples of building works which would need building regulations approval:

  • Internal alterations such as the removal or part removal of a load bearing wall, joist, beam or chimney breast
  • A loft conversion
  • Installation of a new lavatory (not just a replacement) which involves a new connection into a soil pipe
  • Conversion of a house into flats
  • Insertion of cavity wall insulation
  • Replacement of all or part (more than 20%) of the roof covering e.g. retiling

This, of course, is only an overview. If you would like advice about a specific project, we will be glad to help.

© Bonell & Co 2011. This article was published in May 2011 as part of the Resources section of our website.

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