Homeowners often use the phrases interchangeably, but in England planning permission and Building Regulations approval are separate processes run by different parts of the council—or, for building control, sometimes by an approved private inspector.
Planning permission (and permitted development)
Planning deals with whether development is acceptable in land-use terms: appearance, scale, layout, impact on neighbours, highways, heritage and consistency with local policy. If your work is not covered by permitted development, you will need a planning application (commonly a householder application for domestic extensions). Even when planning is not required, you may still want a Lawful Development Certificate for certainty.
Building Regulations
Building Regulations set technical standards for safety, health, energy and accessibility in buildings. Most structural work, alterations to thermal elements, drainage, electrics in defined areas, and new habitable space must comply. Compliance is usually demonstrated through a Building Regulations application (full plans or building notice, depending on the project) and inspection stages on site.
Typical combinations
- Permitted development extension + Building Regulations — common for smaller rear extensions that meet PD limits.
- Planning approval + Building Regulations — when you need planning consent and must satisfy structural and energy standards.
- Internal refurb — may need Building Regulations (e.g. structural knock-through, new bathroom drainage) even when no planning permission is required.
Practical takeaway
Before you sign a contract for building work, be clear: Who is producing drawings for planning and building control? What approvals are already in place? When will inspections happen? A professional builder should programme work so that structure, insulation and drainage are exposed for the right stages of sign-off.
Related: Planning permission for extensions and garage conversions.
Disclaimer: General information only—not legal advice. Confirm requirements with your local planning authority and building control body.