How we get paid
Short version: a lead-generation fee from our partner when you submit an enquiry. Never anything from you, and never a cut of what you pay a builder.
The arrangement, in full
When you complete the quote form, your enquiry is passed to our lead partner Bark, which forwards it to extension specialists in your area. Bark pays us a fee for the enquiry. That fee is paid whether or not you go on to hire anyone, and it does not change depending on which specialist you choose or how much the job costs.
What that does and does not influence
- It does not affect your price. You pay us nothing, and the fee is not added to any quote you receive.
- It does not decide who contacts you. Which specialists receive your enquiry is a function of who covers your postcode and is taking work — we do not rank, prioritise or promote individual firms, and nobody pays us for placement on this site.
- It is why the guides are free. The planning and cost content costs money to research and keep current; enquiry fees are what pay for it.
- It gives us an interest in you completing the form. That is exactly why the guides are written to be useful whether or not you do — and why pages tell you when an extension is the wrong answer, or when permitted development means you do not need to spend money on an application.
Related sites
House Extension Expert is operated by SharpCode Ltd, a company registered in England and Wales (number 16031384), registered office Suite 6585, Unit 3a, 34–35 Hatton Garden, Holborn, London EC1N 8DX, which also operates BestBuilders.co.uk. The 2026 regional cost model quoted here is maintained there. Where we link between the two, that is a link to a site the same company owns, and we say so rather than presenting it as independent corroboration.
No advertising, no affiliate links
We do not run display advertising, sponsored posts or affiliate links to products on this site. If that ever changes, this page changes first and any paid placement will be labelled on the page it appears on.