The house in the films
It does not exist. It is a 1930s brick semi somewhere in England, getting a single-storey kitchen extension at the back. Every still and film on the site was made for this guide from generated images, so the drawings, quotes and people in them are not real. People are seen from behind or at a distance, and no paperwork in the frame can be read. We did this on purpose: the films set the scene for each stage, and the figures and rules belong in the text.
Who is who in a building project
The same roles turn up in every chapter, so here they are once.
You, the client
The homeowner paying for the work. In CDM 2015 terms, a domestic client whose legal duties pass to the builder or designer.
The designer
An architect, architectural technologist or surveyor. Draws the scheme and may run the contract.
The builder
The main contractor who signs the building contract and employs or manages the trades.
Building control
The council's service or a registered building control approver. Checks the work meets the Building Regulations.
How the three tools work
The quote comparison, payment schedule and route chooser are short scripts that run in your browser. Nothing you type leaves your device. The quote tool remembers your figures in local storage until you clear them. The arithmetic is shown under each tool, and the scripts are tested with the worked examples used in the chapters.
How facts are checked
Legal and procedural points come from the source: GOV.UK, legislation.gov.uk, HSE, HMRC, JCT, the Planning Portal and Parliament's bill pages. Prices are typical ranges for England in 2026 with the basis stated, built from published fee scales, council charging schedules and trade price guides. Where a figure varies locally, such as building control charges, we say so and point to where to find yours. This review was completed in November 2026.
What this site will not do
- Recommend, rate or refer you to a builder, designer or design and build firm.
- Take enquiries: you will not find a form, inbox or phone line here, by design.
- Give legal, financial or surveying advice on your project. For that, see a construction solicitor, a chartered surveyor (RICS) or an architect registered with the ARB.
Any firm that traded under this name or domain before is unrelated to this guide.