Within Tolerance
A socket tester plugged in beside a crooked socket with paint on it.

Electrics and sockets: what to test, and the certificate to keep

The checklistThe detail

Try every light and switch, and test every socket with a plug-in tester. Find the consumer unit (the fuse box), check its circuits are labelled, and press its test button. Test the smoke and carbon monoxide alarms. Ask for the Electrical Installation Certificate, not an EICR. Faults go on your snag list.

On the day

13 checks

Do the every-room checks first: Every room. These checks go through the whole house.

Lights, switches and sockets

Why and how

Fuse box and alarms

Why and how

Fans and outside

Why and how

If something fails, add it to your snag list and report it to the builder. How to report a snag

Next: Your first week

The detail, for reading before you go

The consumer unit and its test button

The consumer unit is the box of switches that controls the circuits in your home. Electrical Safety First says modern ones have a main switch and fuses or circuit breakers. To check yours has an RCD (residual current device, a safety switch), look for a button marked T or Test.

Press the test button. It should switch off the power to the parts of the home the RCD protects. Then switch it back on. The IET says the label on a consumer unit now advises pressing it every six months.

The official checklist expects the unit to be labelled, with blanks filling any empty slots so there are no gaps. Labels matter later. When a breaker trips, you want to know which circuit it is.

Why does my fuse box keep tripping?

Repeated tripping is worth reporting. Electrical Safety First lists circuit breakers tripping, along with burn marks on plugs and sockets and buzzing or crackling sounds, as signs to get the electrics checked as soon as possible. In a new build, report it to the builder. The NHQB treats a total loss of power as an emergency for the builder to fix as soon as possible, not a snag.

Do I need to test every socket?

Yes. The official inspection checklist says all sockets should be tested with a plug tester. The NHQB lists outlets or switches that don't work as possible snags.

Take care

Know the limits of a cheap tester. Electrical Safety First says simple plug-in testers can mislead you into thinking a socket is safe when it isn't. They can't measure how well the earth is working. A tester will generally show whether a socket works, and catches some wiring faults. It is no substitute for the electrician's own tests.

A trick we used a pack of sticky notes. Any socket or switch that failed got a note on it there and then. By the end, the notes were our electrical snag list.

Which electrical certificate should I get?

An Electrical Installation Certificate (EIC). NICEIC says you get an EIC after any new installation or major alteration. It records the results of testing and confirms the work is safe and meets the regulations at the time. An Electrical Installation Condition Report (EICR) is a different thing: a check on an existing installation.

A new home also needs a Building Regulations compliance certificate. NICEIC says this is required for notifiable work, which includes a new full electrical installation, such as a new build. Keep both with your home's paperwork. If you don't have them, ask the builder.

For later: NICEIC says homeowners are strongly encouraged to have an EICR at least every 10 years.

Smoke, heat and carbon monoxide alarms

The official checklist expects every smoke, heat and carbon monoxide detector to be present, with its power light on. Check they work. Electrical Safety First says there should be at least one smoke alarm on each floor, with a heat detector in the kitchen. It suggests testing them regularly, ideally every week.

Extractor fans

Bathroom and en-suite fans usually come on with the light. The checklist says to make sure the fan's own switch (the spur) is on, then check it runs when the light goes on. In a bathroom without a window that opens, building regulations guidance says an intermittent fan (one that switches on and off) should keep running for at least 15 minutes after you leave the room. The bathrooms page has more on fans.

Is an EV charge point included?

Often, if you have parking. Under building regulations in force in England since June 2022, a new home with its own parking should have access to an electric vehicle charge point. Each one should have an output of at least 7kW. There is a cost cap. Where the connection would cost more than an average of £3,600 per charge point, cable routes are fitted instead, ready for a charger later. Ask the builder which you are getting before completion.

Can I add extra sockets?

Yes, but think about when. NICEIC says moving or adding a socket should come with a Minor Works Certificate. Adding a new circuit is notifiable work and needs building regulations sign-off. Premier Guarantee lists electrical work as an alteration, and says damage caused by alterations isn't covered by the structural warranty. Before you add anything in the first two years, check with the builder.

Where you'll want extras is personal. Think about the hallway, the loft, the garden and where the TV will really go.

From our own build

We had an extra socket put in under the stairs, and we rate it highly.

Where this comes from

Every fact on this page comes from the documents below. Anything marked ‘a trick we used’ is our own.

Official and industry guidance

  1. New Homes Quality Board, Pre-Completion Inspection Checklist: House, Version 2, March 2026, p.4, p.9, p.10, p.17
  2. Electrical Safety First, RCDs explained, web page, retrieved 9 October 2026
  3. Ministry of Housing, Communities and Local Government, Approved Document S: Infrastructure for the charging of electric vehicles, 2021 edition, 2021 edition, in force 15 June 2022, 6.2, S1, 44D
  4. The IET, BS 7671 FAQs: Consumer units and protective devices, web page, retrieved 9 October 2026
  5. Electrical Safety First, Electrical Safety Advice for DIY-ers, web page, retrieved 9 October 2026
  6. New Homes Quality Board, A homeowner guide to snagging, May 2026, Emergencies that require immediate attention, Other possible snags and defects
  7. Electrical Safety First, Best Practice Guide 8: Selection and use of plug-in socket-outlet test devices (Issue 2), February 2015, p.6, p.10
  8. NICEIC, Electrical Installation Condition Reports (EICRs), web page, retrieved 9 October 2026
  9. NICEIC, The NICEIC Help Hub: FAQs for householders and landlords, web page, retrieved 9 October 2026
  10. Ministry of Housing, Communities and Local Government, Approved Document F: Ventilation, Volume 1: Dwellings, 2021 edition, 2021 edition, in effect from 15 June 2022, 1.51
  11. Premier Guarantee, Home maintenance tips, undated, retrieved October 2026

Last checked 15 October 2026

For general education only. It isn't legal or surveying advice. Always check your own warranty documents and Code version, and speak to your housebuilder, your warranty provider or a qualified snagging inspector before relying on it. Read the disclaimer.