Expansions can differ massively, from two-story ones double the size of a house, to the expansion of an additional first floor room. Since they are so different, it is hard to put a figure on the amount they cost or how much value they will add on to your property. Statistics show that a double storey extension can add as much as 20% to the value of your property. That is if the property is worth £200,000 with a double storey extension can potentially increase to £240,000.

An expansion done well that can be a key selling point – and one you can appreciate for a long time as an owner.

Deciding on whether to do a double or single storey extension can be a very stressful experience. This is why we are here, we offer unlimited independent construction advice completely free of charge to go through your options and help you through your decision making process. Even if you decide to reward your project to a different company other than us, we can come up with an arrangement with you for us to monitor whoever is in charge of your project and see whether they are delivering a good job or not.

Planning Application

From £999*

  1. Draft designs until confirmation
  2. Full expert advice and support
  3. Includes providing options for the client and revising with them
  4. For applications in Conservation Areas a Design and Access Statement will be required, Extension Architecture can help provide this for an additional fee (price dependent on the scope and complexity)
  5. As your agent we will submit to the council

Building Regulation

From £900*

  1. Draft design until confirmation
  2. Full expert advice and support
  3. To make amendments to drawings where necessary
  4. Can advice for a Structural Engineer to obtain structural calculations (fees separate)
  5. Can guide client in submitting for building control (additional fees applicable where necessary)

Site Survey

From £250*


  1. Site survey by one of our team of experts
  2. Consultation of proposed plans
  3. Full site measurement survey
  4. Photographic survey

Submission Fees

Planning Application Fee to council (£172) not included
Permitted Development Fee to council (£86) not included
Our expert team will liaise with the council and handle the full submission process.