Home Rewire Services in Hertfordshire | Thomsett Electrical

Extension and Renovation Electrics

Second fix wiring on a house extension in Hertfordshire

An extension is only as good as the electrics behind the plaster. Thomsett Electrical wires extensions, loft conversions, garage conversions, knock throughs and full house renovations across Hertfordshire, working to your builder’s programme.

What we do on a renovation

  • A design meeting before first fix, so sockets and switches end up where you actually want them
  • First fix wiring, back boxes and containment
  • Consumer unit upgrade or a new board if the existing one cannot take the extra circuits
  • New circuits for kitchens, utility rooms, bathrooms and garden rooms
  • Underfloor heating supplies and controls
  • Lighting design, including feature and outside lighting
  • Second fix, testing and full certification for building control

Get the electrician in early

The most expensive mistakes on a renovation are the ones made before the electrician arrives. Ceiling heights, joist runs, where the boiler sits and how the kitchen is laid out all change what is possible.

We would rather spend an hour with you and the builder at drawing stage than chase cables through a finished ceiling.

Working with your builder

We are used to being one trade among several. We book our first fix and second fix into the builder’s programme, turn up when we say we will and leave the site tidy for the plasterer.

Common questions

When should I book the electrician?

As soon as you have drawings. First fix has to happen before plastering and the board may need upgrading before that, so early booking saves delays.

Will my existing consumer unit cope?

Often not. An extension usually adds several circuits. We check the existing board and tell you whether it needs upgrading as part of the job.

Do you handle the certification?

Yes. We are NAPIT registered, so we certify the work and notify it and you get the paperwork for building control.

Can you rewire the rest of the house at the same time?

Yes. It is usually the cheapest time to do it because the floors are already up.

More from Thomsett Electrical

Send us your drawings or a few photos of the space and we will price the electrical works for the whole project.

Customer Reviews

3 quick simple steps

Give us a call or send us a message through WhatsApp. We're here and ready to help you.

We will provide your free quote over the phone when possible, or arrange a convenient home visit if needed.

Once you approve the quote, we will complete the job efficiently, safely, and to the highest safety standards.

Quick & Simple!

Proudly serving Hertfordshire & all surrounding areas

208 Caxton Rd, Hoddesdon EN11 9NY, UK
208 Caxton Rd, Hoddesdon EN11 9NY, UK

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