Groundwork
Foundations, drainage, and getting out of the ground
5 tasks in this phase
1 Free with email
Foundations and Footings: What Goes in the Ground Before Anything Goes Up
What type of foundations your extension needs, how deep they go, what they cost, and what to expect on dig day.
2
Drainage
Foul and surface water drainage for your extension: what connects where, gradient rules, build-over agreements, soakaway requirements, and what building control inspects before backfilling.
3
Building Control Foundation Inspection: What to Expect
Your BCO must inspect open foundation trenches before concrete is poured. Here's what they check, what 'bottoming up' means, and how to prepare so nothing delays the pour.
4
Building Control Inspection: Drainage and Oversite
Two BCO inspections stand between your foundations and the floor slab. Here's what the inspector checks at the drainage and oversite stages, how to prepare, and what happens if you cover the work too early.
5
Damp Proof Course: The Cheapest Thing That Causes the Most Expensive Problems
Why the DPC matters, how it connects to your existing house, and the common mistakes that cause damp problems later.