Planning permission approved: what happens next?

The decision email arrives and the project suddenly feels real. It is tempting to call a builder and book the earliest available date.

Before you do, make sure everyone means the same thing by “ready to build”. Planning approval usually establishes what development is acceptable. It does not settle every construction detail, obtain every other consent or appoint the people who will manage the work.

Start with the decision notice

Read the full notice with your designer, including the approved drawing list, conditions and any informative notes. A condition might require details or approval at a particular point, such as before development starts or before certain materials are used.

Create a short action list: what is required, who will prepare it and when it must be resolved. Pre-commencement conditions can prevent a lawful start until their requirements have been met. Do not assume they can be dealt with after the foundations are dug. Government guidance on planning conditions.

Check the permission's time limit too. If you bought the house with an old approval, ask your planning adviser to check its status and the evidence of any earlier work. A previous owner's description of having “started it” is not enough to settle the position.

Move from appearance to construction

Planning drawings commonly show the layout, size and external appearance of a proposal. The technical package develops how the work will be constructed: foundations, floor and roof build-ups, insulation, drainage, ventilation and other relevant details.

Structural design needs to fit those drawings. Beam depths can affect ceiling levels. Posts can affect kitchen units. Drainage routes can affect the position of a new WC. Resolving these relationships before ordering products reduces the risk of costly changes.

Ask which decisions you must make now. Window sizes, rooflights, heating arrangements and the general kitchen layout can influence technical work even if you have not selected every handle or tile.

Arrange the building control route

Planning and building regulations are separate. For an ordinary house extension, agree the appropriate building control route and identify the body handling it. In England, this will generally be the local authority or a registered building control approver. How to apply for building regulations approval.

A local authority full plans application allows detailed proposals to be checked. A building notice does not give the same formal plans approval and is unsuitable for some work. Choosing a route does not remove the need to resolve technical details.

Confirm who is submitting information, answering queries and notifying building control at the relevant stages. The drawings being finished and the application being made are separate tasks.

Check the matters outside planning

Ask whether the project affects a party wall, nearby foundations, public drainage, a protected tree or land you do not own. Check any relevant lease, covenant or access arrangements with your legal adviser.

These checks can change the practical programme. For example, a rear extension might be acceptable in planning terms but need the drainage design adjusted before the sewerage company will accept the proposals.

Keep a single list of outstanding matters. “Planning is approved” should not obscure an unanswered question about access for scaffolding or where a new inspection chamber will go.

Give builders the same information

Early conversations can help you understand availability and broad cost. For a detailed comparison, issue the same drawings, specification and scope to each shortlisted contractor.

Identify items you will buy yourself and anything still undecided. If a kitchen is excluded, say whether the builder must still allow for its plumbing, electrics and installation. State whether decorating, flooring and reinstating the garden are included.

Ask for exclusions and provisional allowances to be listed clearly. A price becomes more useful when you can see what might change it.

Agree who does what during the build

Before appointment, establish who will answer design queries, authorise changes, assess payments and coordinate any separate trades. Put the contractor's scope, payment arrangements and programme into an appropriate written contract.

Professional site support is also a defined service. A designer answering a technical query, a contract administrator assessing an application for payment and a project manager coordinating progress are different activities. Agree the support you need and the scope of each appointment.

Make a decision diary

An illustrative diary might record that the rooflight model must be confirmed before roof details are finalised, the drainage response is due before the start date is fixed and the electrical layout is needed before first fix.

For each item, record the decision, the person responsible and the latest sensible date. This turns a vague list of things to choose into a workable programme.

Keep control of changes

If you alter the approved design, ask your designer whether the planning position, building control information or structural calculations need updating. Changing the size of an opening on site can affect several parts of the design at once.

Record the revised scope, price and programme impact before authorising the change. Make sure the team uses the same current drawing issue.

Your next step

Gather the decision notice, approved drawings and any conditions correspondence. CR Design Services can help develop the building regulations and structural information and discuss support through tendering and construction. Explore the technical design service.

Applies to homes in England. Guidance checked 7 September 2026.