Home extensions and renovations Extensions: running the project

There's a lot to consider when building an extension

There's a lot to consider when building an extension

Building an extension is a complicated job, with a long list of key stages.

Planning the build

  • Decide where you want the extension
  • Work out your maximum and minimum budget, and how much you have for a contingency
  • Create the plans for your extension
  • Run the plans past your neighbours
  • Apply for planning permission and building regulations approval
  • Make any required changes to the plans
  • Appoint contractors or sub-contractors.
  • Agree with neighbours any times during the day you can start and finish the build
  • Organise your current space to provide easy access for contractors and less disruption for yourself (for example, if you have a spare bedroom, consider making it a temporary sitting room away from the mess)

Construction

  • Create the foundations, including drainage
  • Build the walls
  • Construct the roof
  • Put in the windows and external doors
  • Create internal partitions
  • First fix electrics, plumbing and telecommunications
  • Insulate the extension
  • Finish the walls and plaster
  • Install the heating
  • Second fix electrics, plumbing and telecoms
  • Fit internal doors, skirting and other carpentry
  • Decorate and furnish
  • Get appropriate certificates

During this time you will also need to sign off from building control. 

Employing contractors and sub-contractors

You have a choice of using one company or main contractor to do everything for you from start to finish – including getting planning and building regulations approval – or you could bring in sub-contractors, employing an architect through to bricklayers, roofers and general builders. 

Which? works for you