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Extensions by Mitchell & Andrew Building Services

Extensions

Single and two-storey home extensions across Cornwall, managed in-house from groundwork and structural work through to finishing.
Established Truro & Falmouth builder
Real photos of our own work
Rated 5.0 on Google

Frequently Asked Questions

Do I need planning permission for an extension?
Some single-storey rear extensions are permitted development, but many need planning permission, and almost every extension needs building regulations approval. A firm price comes from the approved drawings.
Can we stay in the house during the build?
Usually, yes. Most of the work is outside until the extension is weathertight, and the opening into the house is made near the end. We go through access and the noisy stages with you before we start.
Do you organise the roofer, plumber and electrician?
Yes. We use the same subcontractors on our builds and schedule them in, so you deal with us rather than with separate trades.
How long will my extension take?
That depends on its size, the ground and the weather. You get a programme with the quote, and we keep you updated as the build goes on.

An extension usually starts with a room that no longer works: a kitchen that is too small for the family, no space for a utility, or a need for an extra bedroom with its own en-suite. We build single and two-storey extensions across Cornwall, mostly in and around Truro, Falmouth, Perranwell Station and Playing Place.

We work from your architect's drawings and the building regulations approval. Our own team sets out and digs the footings, pours the foundations, builds the blockwork, forms the openings and puts up the roof structure, then returns for first fix, second fix and finishing once the shell is weathertight. The roofing, plumbing and electrical work goes to the subcontractors we use on every build, booked into the programme so the job does not stall waiting for the next trade.

Joining the new space to the house is the part that needs most care. Where the extension opens into an existing room, the right support goes in over the opening first, and the outside is finished in render, timber cladding or stone so it sits with the original building. The two-storey extension in render and timber cladding in our gallery is one of ours.

Customers tend to mention how the job was run. Michael Padmore had a large extension built and said communication was clear from start to finish. John Mayo's extension in Falmouth was finished in brilliant time, and M J P wrote that costs and billing were transparent and the build came in on time and on budget. Sally Tregoning's project cleared an old garage, office and WC and replaced them with an en-suite double bedroom, utility, workshop and double garage.

The price depends mainly on the size and number of storeys, the ground and foundations, how the extension joins the house and the finishes you choose.

What our customers say

“I wanted to improve part of my property and was looking for a team with a professional approach. I appreciated the clear communication and attention to detail throughout the process. Really pleased with the experience.”

Hickson

“I was so lucky and thankful that I came across Mitchell and Andrew building contractors. From the very prompt visit and quotation to the completion of works (complete new bathroom) I was very impressed. They were clean, punctual, reliable and professional and I would choose them for any future projects, I cannot praise them high enough. Thank you Miles, Marc and Vinny.”

Pat Williams

“Miles and his team are simply incredible, the attention to detail is second to none . Thanks Again for making our dreams come true!!! 💃🏼”

Ashley Miller

Contact

Or call us on 07557 905703

Details that help

  • The property address and whether you are thinking of one storey or two.
  • What the new space is for, such as a kitchen-diner, bedroom or garden room.

Add up to 5 photos of the job.