Building Regs for Trades: What Needs Approval

Most structural, safety-critical and energy work on a home needs Building Regulations approval — but a large chunk of it you can sign off yourself if you belong to a competent person scheme. Knowing which side of that line a job falls on is the difference between a clean handover and a customer who cannot sell their house two years later. This guide covers what needs approval in England and Wales in 2026, what you can self-certify, and what happens when work goes unnotified.

Building Regulations vs planning permission — not the same thing

Trades mix these up constantly, so it is worth nailing down. Planning permission is about whether a building can go up or change in principle — its size, use and appearance. Building Regulations are about how the work is actually done: structure, fire safety, insulation, ventilation, electrics and drainage. A job can need one, both or neither.

A rear extension might need planning permission and building control. Replacing a boiler needs no planning application, but it is notifiable under Building Regulations. Repainting a fence needs nothing. This guide is only about the Building Regulations side, which is where most day-to-day trade work sits.

The jobs that almost always need building control

Some work is notifiable no matter who does it. If you are touching any of the following, assume building control is involved until you have confirmed otherwise.

Structural alterations — removing or altering a load-bearing wall, forming a new opening, underpinning, or anything that changes how a building carries its load. Anything involving a steel beam almost always needs sign-off and usually a structural engineer’s calculations.

Extensions and loft conversions — new floor area, dormers, and conversions of a loft or garage into habitable space. Fire escape, insulation and structural requirements all come into play.

Drainage and waste — installing or altering underground drains, or building over or near a public sewer.

New heating appliances — boilers, flues, and fixed combustion appliances. Gas work must be done by a Gas Safe registered engineer; oil and solid fuel have their own schemes.

Window and door replacements — replacing existing windows or external doors is notifiable because of thermal performance and, in some rooms, means of escape.

Certain electrical work in dwellings — covered by Part P, which has its own section below.

What you can self-certify through a competent person scheme

Here is the part that saves trades time and money. For a lot of common work, you do not have to submit a building control application at all — if you are registered with the right competent person scheme, you can carry out the work and self-certify that it meets the regulations. The scheme notifies building control on your behalf and the homeowner gets a compliance certificate.

The schemes are trade-specific. Gas Safe covers gas appliances. NICEIC, NAPIT, ELECSA and others cover Part P electrical work. FENSA and CERTASS cover replacement windows and doors. There are schemes for solid fuel, oil, microgeneration and more.

The practical point: if a job is within your scheme’s scope and you are registered, you skip the building control application, the inspection visits and the fee. If you are not registered, the same job means a full building control notice and inspections — slower and more expensive for your customer. For a working trade, scheme membership usually pays for itself on convenience alone.

Notifiable vs non-notifiable — the everyday grey area

Not everything needs telling anyone about. Like-for-like repairs and minor work generally are not notifiable: replacing a tap, swapping a light fitting on an existing circuit, re-tiling, plastering, or fitting a new kitchen unit where you are not altering services.

It gets notifiable the moment you affect structure, fire safety, energy efficiency or a protected service. Moving a socket in a kitchen or bathroom, adding a new circuit, or altering the consumer unit crosses into Part P territory. Knocking through, even a small opening, is structural. Swapping a window is thermal.

When you are genuinely unsure, the safe move is a quick call to the local authority building control team or your scheme’s technical line before you start — not after. It is a five-minute conversation that can save a re-inspection.

Two routes when the job is not self-certifiable

If a job needs building control and you cannot self-certify it, there are two application routes. A full plans application means you submit drawings and details before you start, and building control checks them up front — sensible for extensions and structural work where you want certainty before spending. A building notice is lighter-touch: you notify building control shortly before starting and they inspect as the work progresses. It suits straightforward jobs but carries more risk, because problems surface on site rather than on paper.

Either way, work gets inspected at key stages and, once it is signed off, the homeowner receives a completion certificate. That certificate is the document that matters when the property is sold.

What happens if work goes unnotified

This is the part worth spelling out to customers who want to cut corners. Unnotified work does not just risk a safety problem — it creates a paper problem that surfaces years later. When the homeowner comes to sell, the buyer’s solicitor asks for Building Regulations certificates. If they are missing, the sale stalls. The owner then has to apply for retrospective approval (a regularisation certificate), pay for it, and sometimes open up finished work so it can be inspected. Occasionally they have to buy indemnity insurance to get the sale over the line.

Local authorities also have enforcement powers and can require non-compliant work to be altered or removed. The liability tends to land on the homeowner, but the trade who did the work unnotified is the one who gets named — and the one who loses the reference and the repeat business. Doing it properly is cheaper than the alternative every time.

FAQ

Do I need building regs to move a socket? If you are altering circuits in a kitchen, bathroom or other special location, or adding a new circuit, it is notifiable under Part P. A straight like-for-like accessory swap on an existing circuit generally is not. When in doubt, treat it as notifiable.

Can I self-certify if I am not in a competent person scheme? No. Self-certification is only available to members of the relevant scheme. Without it, the same work needs a full building control application and inspections.

Who applies to building control — me or the homeowner? Either can, but in practice the trade or a building control body handles it. If you self-certify through a scheme, the scheme notifies building control for you and the certificate goes to the homeowner.

How long does approval take? A building notice can be lodged shortly before work starts. A full plans application takes longer because the drawings are checked first — allow several weeks. Self-certified work has no wait at all.

What is a regularisation certificate? It is retrospective approval for work that was done without building control being notified. The homeowner applies, pays a fee, and building control inspects what they can — sometimes meaning finished work has to be opened up.

Does replacing a window really need notifying? Yes. Replacement windows and external doors are notifiable on energy-efficiency grounds. Most installers handle it through FENSA or CERTASS so the homeowner gets a certificate automatically.

Get the compliant work, not just any work

The trades that win on jobs like these are the ones who do the paperwork properly — and those are the customers worth having. Trade Pilot is built to send you local homeowners who want the job done right the first time. It is free to join and only charges when a real job in your area lands in your inbox, with each lead sold to no more than three trades so you are not undercutting a queue of ten. You quote the work knowing you can actually win it.

Related reading: do I need planning permission? · do I need Part P · UK trade compliance handbook · the Building Safety Act for tradespeople