Before you start building: a homeowner's practical checklist

The builder has a possible start date and you are ready to get moving. Before you confirm it, gather the outstanding decisions into one place.

For each heading below, record whether it applies, what evidence you have, who is responsible and what remains to be done. “Not applicable, checked by our designer” is a useful answer. An unexamined assumption is not.

This guide concerns extensions and alterations to ordinary homes in England. Flats, separate dwellings, listed buildings and more complex projects can involve additional requirements.

1. Establish the planning position

Four terms are easy to mix up:

Planning permission is an approval for development through a planning application. Permitted development is planning permission granted nationally for defined types of work within conditions and limits. Prior approval is an additional procedure required for some permitted development. A lawful development certificate formally confirms the lawfulness of the development described in it.

Ask which route applies to your actual proposal and keep the relevant written advice or decision. Check restrictions and previous alterations. Your neighbour's approval does not establish your own position. Householder permitted development guidance.

Your record: the route, relevant drawing versions, decision reference where applicable and any outstanding action.

2. Read the conditions and confirm the timing

Where permission has conditions, ask which need action before work, before a particular operation or before use. Keep evidence of approvals required to discharge those conditions. Do not rely on the headline decision alone. Planning conditions guidance.

Check that the permission remains capable of implementation. If earlier work is said to have kept an old approval alive, have the evidence assessed. Also ask whether Community Infrastructure Levy procedures or an exemption application apply before commencement. Community Infrastructure Levy guidance.

If the design has changed since approval, resolve whether further planning action is needed before the changed work is undertaken.

Your record: a condition schedule with actions, responsible people and dates.

3. Confirm building control arrangements

Identify the building control body, the application route and what must be in place before the relevant work starts. For ordinary domestic work in England, the body will generally be the local authority or a registered building control approver. A local authority full plans application and a building notice do not provide the same type of upfront review. Building control application routes.

Ask who will submit information, notify the start and book inspections. Agree how concealed work will be inspected before it is covered. Obtain a list of completion information expected for the project.

Building control inspections are part of a compliance process; they do not replace the contractor's responsibility for its work or any professional site-monitoring service you appoint.

Your record: body, reference, contact, outstanding queries and inspection responsibilities.

4. Check party wall and neighbour matters

Work to a party wall, certain boundary works or excavation near a neighbouring structure can engage the Party Wall etc. Act. The correct process depends on the proposed work. Do not assume that all work near a boundary requires the same notice, or that friendly verbal agreement resolves every requirement. Party walls and building work.

Discuss the proposal early and obtain advice where needed. Allow for the applicable notice period and any process needed to resolve a dispute. Planning consultation and party wall procedures are separate.

Also check practical access. Scaffolding, deliveries or temporary works on neighbouring land require a properly established basis for access. A planning approval does not, by itself, grant that right.

Your record: advice received, notices and responses where required, and agreed access arrangements.

5. Resolve drains, services and investigations

Confirm the location and ownership of drainage affected by the work. Identify whether consent to build over or near a public sewer is required and obtain the relevant response. In Northumbrian Water's wastewater area, its published trigger includes a public sewer within 3 metres of the proposed work. Other providers have their own processes. Northumbrian Water guidance.

Identify gas, electrical, water and other services that may need protection or alteration. Ask whether further structural opening-up, ground investigation or an asbestos survey is needed for the planned work. The type and extent of investigation should follow the building and scope, rather than a generic checklist alone.

Your record: confirmed information, unresolved risks and who is arranging specialist work.

6. Check property and site restrictions

Ask whether listing, conservation controls, protected trees or ecological constraints affect the work. These are reasons to establish the position, not to assume that every project is prohibited or needs the same application.

If you are a leaseholder, check the lease and required consents. Ask your legal adviser about relevant covenants, boundaries or rights where uncertainty could affect the proposal. If you are still buying the property, establish access and permission for investigations with the current owner.

Your record: restrictions checked, necessary consents and any limits on site access or timing.

7. Name the people responsible for design and construction

Agree the appointments and scopes. Know who coordinates the drawings, who is responsible for structural design and who controls the building work. Where principal designer and principal contractor roles apply, confirm who fulfils them.

The Building Regulations principal designer coordinates design compliance. The CDM principal designer coordinates health and safety during the pre-construction phase. They are distinct roles, even when one competent organisation undertakes both. Domestic-client rules affect how duties are allocated, so confirm the arrangements for your project in writing. Building Regulations duties, HSE guidance for domestic clients.

Your record: named appointments, scope of services and a contact list.

8. Settle the contract and budget

Check that the contractor's price refers to the current drawings and agreed scope. List exclusions, direct purchases and provisional allowances. Make sure installation responsibilities are clear for items you supply.

Use an appropriate written contract covering the work, payment arrangements, programme and changes. Confirm who can authorise additional work. Keep a project budget that includes commitments made directly to suppliers and remaining contingency.

Discuss insurance with the relevant insurers, including the existing building and the works. Do not assume that an ordinary household policy covers every aspect of a building project.

Your record: signed contract, accepted scope, current budget and confirmed insurance arrangements.

9. Agree how the site will operate

Discuss access, welfare, working hours, waste, parking, deliveries and security. If the home remains occupied, agree how people will be separated from the works and how essential facilities will be maintained.

Confirm who arranges the construction phase plan and any temporary works planning or design. Health and safety arrangements should reflect the project, including structural alterations and the needs of an occupied home. HSE: domestic construction projects.

Decide how queries and changes will be recorded. A short regular meeting with an action list is often more useful than relying on several separate message threads.

Your record: site arrangements, key responsibilities and the communication routine.

10. Agree what you will receive at handover

List the completion information relevant to the work: building control documentation, appropriate installation certificates, product instructions, guarantees and records of changes. Confirm who obtains each item and who will resolve outstanding work.

Ask for a demonstration of heating, ventilation and controls. Keep the information together so it is useful for maintenance and any future sale.

Your record: a handover schedule agreed before completion becomes urgent.

The final start-date check

□ The planning route is established and time-critical conditions addressed. □ The relevant building control arrangements and notices are in place. □ Party wall, access and other necessary consents are resolved for the work starting. □ Drainage and significant site uncertainties have been assessed. □ The team has the coordinated information needed for the next stage. □ Design and construction responsibilities are clear. □ The contract, payment arrangements and overall budget are agreed. □ Site safety, occupation and insurance arrangements have been addressed. □ Outstanding decisions have named owners and realistic deadlines. □ Inspection and handover responsibilities are recorded.

How CR Design Services can help

If you have drawings but are unsure what is missing before construction, send us the information you have. We can review the design stage, identify the next work needed and discuss the scope of support appropriate to your project. Talk to us about getting ready to build.

Applies to ordinary domestic projects in England. Guidance checked 7 September 2026. The checklist should be adapted to the property and proposed work.