Building Regulations vs Planning Permission: What's the Difference?

The key differences between building regulations and planning permission, when each is needed, and why you often need both.

One of the most common sources of confusion for homeowners is the difference between building regulations and planning permission. They are two completely separate systems, managed by different teams, covering different things - and for most building projects, you need both. Getting one does not mean you have the other.

What Is Planning Permission?

Planning permission controls what you build and where. It is about whether your proposal is appropriate for the location - its size, design, impact on neighbours, effect on the streetscape, and compliance with local planning policies.

Planning permission is managed by the planning department of your local council. The decision considers factors like:

• Is the development in keeping with the character of the area?
• Will it harm neighbours' light, privacy, or amenity?
• Does it comply with local plan policies?
• Are there heritage, environmental, or highway concerns?

For a full guide, see do I need planning permission?

What Are Building Regulations?

Building regulations control how you build. They are national technical standards that ensure buildings are safe, healthy, energy-efficient, and accessible. They cover the physical construction of the building - not whether it should be there in the first place.

Building regulations are managed by Building Control - either the council's building control team or a private Approved Inspector. They cover:

• Structure (Part A) - foundations, walls, floors, and roofs must be structurally sound
• Fire safety (Part B) - means of escape, fire detection, fire-resistant construction
• Hygiene (Part G) - hot and cold water supply, bathrooms, kitchens
• Drainage (Part H) - foul and surface water drainage
• Ventilation (Part F) - adequate ventilation to all habitable rooms
• Energy conservation (Part L) - insulation, airtightness, heating efficiency
• Electrical safety (Part P) - safe electrical installation
• Access (Part M) - accessibility for disabled people
• Sound insulation (Part E) - between dwellings (flats, semi-detached houses)
• Stairs and ramps (Part K) - safe design of staircases, ramps, and guards

Key Differences at a Glance

When You Need Both

Most building projects require both planning permission (or PD confirmation) and building regulations approval. For example:

• House extension - may be permitted development (no planning application needed), but always requires building regulations
• Loft conversion - may be PD for the dormer, but always requires building regulations for the structural work, staircase, fire safety, and insulation
• New house - always requires both planning permission and building regulations
• Garage conversion - usually PD (internal alteration), but requires building regulations for insulation, ventilation, damp-proofing, and fire safety

When You Need Planning but Not Building Regulations

Some works need planning permission but not building regulations:

• Change of use (where no building work is involved)
• Fences, walls, and gates
• Some external alterations (cladding, painting in conservation areas)

When You Need Building Regulations but Not Planning

Many projects that fall within permitted development rights still require building regulations:

• Any extension (single storey, two storey, side, rear)
• Loft conversions
• Garage conversions
• Structural alterations (removing load-bearing walls)
• New heating systems (boilers, heat pumps)
• Replacement windows (unless FENSA registered installer)
• Electrical work in kitchens and bathrooms
• Re-roofing (if changing structure or insulation)

The Building Regulations Application Process

There are two routes:

1. Full Plans Application

You submit detailed drawings and specifications before work starts. Building Control checks the plans and issues an approval notice. This is recommended for larger projects as it gives you certainty that your design complies before you start building.

2. Building Notice

You notify Building Control that you intend to start work, without submitting detailed plans. The inspector checks compliance during site visits. This is simpler and quicker for straightforward projects but carries more risk - if something does not comply, you may need to redo work.

The Completion Certificate

When work is finished and passes final inspection, Building Control issues a completion certificate. This is a critical document - it confirms that the work complies with building regulations and is essential when selling your property. Mortgage lenders and solicitors will ask for it.

If you do not have a completion certificate for previous work, you can apply for a regularisation certificate from your council. This involves a retrospective inspection and typically costs more than the original application.

What Happens If You Skip Building Regulations?

Building work that does not comply with building regulations can have serious consequences:

• Safety risks - structural failure, fire risk, electrical hazards
• Sale problems - solicitors flag missing completion certificates during conveyancing
• Insurance issues - your home insurance may not cover un-approved work
• Enforcement - the council can require you to undo non-compliant work, even years later
• Mortgage issues - lenders may refuse to lend against a property with un-approved building work

Finding a Builder Who Understands Both Systems

A good builder understands both planning and building regulations requirements. When getting quotes, ask:

• Will you handle the building regulations application?
• Who will manage the building control inspections?
• Will you provide a completion certificate at the end?

Find a contractor near you who is experienced with both planning and building regulations compliance.

Planning permission and building regulations are two halves of the same coin. Planning decides if you can build; building regulations decide how it must be built. Make sure you have both covered before work begins.