Building regulations are the technical rules that make buildings safe, healthy and energy efficient. They are separate from planning permission, and nearly every house extension needs approval under them, even if no planning application is required.
Rules differ between England and Wales, and they are updated periodically. Newport is in Wales, so Welsh building regulations and their Approved Documents apply. Confirm current requirements with building control.
What building regulations cover
For an extension, the regulations typically cover:
- Structure: foundations, walls, floors, beams and roof
- Fire safety: escape routes, fire resistance, smoke alarms
- Insulation and energy efficiency: walls, roof, floor, windows and heating
- Ventilation: background vents, extractor fans and air flow
- Drainage and waste: connections to foul and surface water systems
- Electrics and gas: safe installation by qualified people
- Damp and moisture: damp-proof courses and membranes
- Access: where relevant, safe stairs and doors
Two ways to apply
Full plans application
You submit detailed drawings and specifications. Building control checks them and issues a decision, usually within a few weeks. This is the recommended route for most extensions because you know the design complies before building begins.
Building notice
You give notice that work will start and submit fewer documents. It can be quicker to start but carries more risk, because problems might only be discovered on site.
Who does the checking?
You can use your local authority building control (in Newport, this is Newport City Council) or, where available, a private approved inspector/registered building control approver. Fees vary and are normally based on the project value or size.
Typical inspection stages
Building control will usually want to inspect at key points, for example:
- Commencement of work
- Foundation excavation, before concrete is poured
- Foundations and oversite concrete
- Damp-proof course
- Drains, before they are covered
- Structure, such as beams and roof timbers
- Insulation, where visible
- Completion
Your builder should arrange these inspections. Missing a stage can mean uncovering completed work.
The completion certificate
When the work is finished and satisfactory, you receive a completion certificate. Keep it safe: buyers' solicitors will ask for it when you sell, and lack of it can delay or derail a sale. Electrical and gas work should also come with the appropriate installer certificates.
Common problems
- Starting work before approval or without notifying building control
- Poorly insulated floors and walls that miss current standards
- Missing fire safety measures in open-plan layouts, where a new room opens onto an existing stair
- Drains built over or too close to foundations without approval
How it fits with everything else
- Planning permission deals with whether you may build.
- Building regulations deal with how it is built.
- A party wall agreement deals with neighbour rights if you build on or near the boundary.
Work with a builder who handles the process
Abron Contracting builds extensions in Newport and arranges building control inspections as part of the project. Contact us or call 01633379170 to discuss yours.
Frequently asked questions
Do I need building regulations approval for an extension?
Yes, nearly all extensions do, even when planning permission is not required.
What is the difference between planning permission and building regulations?
Planning decides whether the development is acceptable in principle. Building regulations set technical standards for how the work is constructed.
What is a completion certificate?
It is the formal document from building control confirming that the finished work complies with the regulations. Keep it for when you sell.
Can I use a private inspector instead of the council?
In many cases, yes, through a registered or approved private inspector. Confirm what applies in Wales for your project.
What if I already built without approval?
Contact building control. You may be able to apply for regularisation, but it can require opening up work to inspect it.
