ComGas carries out full and partial rewires for homes across Farnham, Guildford and the surrounding area, from whole-house rewires in older properties to extension and renovation wiring phased around an occupied household. Every rewire is tested and certified on completion to BS 7671, the 18th Edition wiring regulations.
Knowing whether a house genuinely needs rewiring — or just targeted remedial work.
Not every wiring concern means a full rewire. Cloth-insulated or rubber-insulated cable, wiring colours from before the 2004 harmonised colour change, no earth conductor present on lighting circuits, or a pattern of C2 observations across multiple circuits on an electrical safety report are all genuine indicators that a rewire is the sensible option rather than repeatedly patching individual faults. A single faulty circuit, or a board that needs upgrading on its own, is a different job.
We look at the actual evidence — cable type, circuit age, the condition and number of existing circuits, and what an inspection has found — before recommending a rewire. Where targeted remedial work genuinely covers what's needed, that's what we propose; a rewire isn't the default answer to every wiring question.
ComGas Services UK Ltd Gas Safe · OFTEC · REFCOM F-Gas · CHAS · Constructionline
How we plan and carry out a rewire
Full or partial, occupied or empty, alongside other building work.
A rewire is planned around the property and the household using it, whether that means a whole-house rewire in an empty property or a phased partial rewire around a family still living there.
Full & Partial Rewires
A full rewire replaces the entire fixed electrical installation; a partial rewire addresses specific circuits, rooms or floors where the rest of the installation is genuinely sound.
Full rewires typically apply to older properties where the cable type, earthing arrangement or circuit age is out of step with current practice throughout
Partial rewires cover specific circuits or areas — a single floor, a kitchen, a loft conversion — where the remainder of the installation doesn't need disturbing
The scope is set from what an inspection or survey actually finds, not assumed from the age of the property alone
Either way, the work is tested and certified to BS 7671 on completion
A rewire in a home people are still living in needs a plan for access, temporary power and disruption before work starts, not just a list of circuits to replace.
Rewires phased room by room or floor by floor so parts of the house remain usable throughout
Temporary lighting and power arrangements agreed for rooms out of action during their phase
Access and timing discussed at survey stage around the household's actual routine, not a generic schedule
Kitchens, bathrooms and areas needing continuous services planned to minimise the time they're without power
Rewiring alongside renovation or extension work has a different rhythm to a standalone rewire, because the electrical first fix has to fit around the building programme rather than the other way round.
First-fix wiring completed before plastering, with sign-off before walls and ceilings close up
New circuits for extensions checked against the existing consumer unit's spare capacity before being added
Sequencing agreed with the wider building programme so access and timing don't conflict with other trades
Second fix — sockets, switches, fittings — completed once decoration is ready for them
Cable routes in solid walls need to be chased in, and it's worth being clear from the outset about where our work ends and where a decorator's or plasterer's begins.
Cable routes chased into walls where surface routing isn't practical or acceptable, and channels filled to a plasterable finish
We don't carry out plastering, painting or final redecoration — that's outside our scope and best left to a decorator once the electrical work is signed off
Chasing routes and outlet positions agreed with you in advance so redecoration can be planned around them
Floor and ceiling access for cable runs restored to a safe, functional state, not a decorated finish
The signs that a rewire is genuinely needed — and the signs it isn't.
The strongest indicators that a full rewire is the right answer are things you can point to directly: cloth or rubber-insulated cable rather than modern PVC, wiring colours from before the 2004 harmonised colour scheme, circuits with no earth conductor at all — common on older lighting circuits — or a consumer unit report showing repeated C2 observations spread across several different circuits rather than one isolated problem. Any one of these on its own is worth investigating properly; several together usually point toward the whole installation being due for renewal rather than one circuit at a time.
What doesn't automatically mean a rewire is needed: a single failed socket or switch, one circuit tripping repeatedly while the rest of the house behaves normally, or an old-looking consumer unit on an otherwise sound and recently-checked set of circuits. These are targeted problems with targeted fixes. We say plainly which situation we're looking at before recommending anything, because a full rewire is a significant undertaking and shouldn't be proposed as the default answer to a single fault.
Cloth or rubber-insulated cable and pre-2004 wiring colours are strong indicators a rewire is due
No earth conductor on lighting circuits is a common finding in older homes
Repeated C2 findings across multiple circuits point to the installation as a whole, not one fault
A single faulty circuit or accessory is a targeted repair, not a rewire
Reviews from real ComGas customers, shown as submitted through Google.
Posted on Google
Nick
3 September 2026
Trustindex verifies that the original source of the review is Google.
Matt from ComGas Services UK Ltd was very professional, polite, friendly and quick installing a new shower in my bath (and at a better height for me) and a much easier press-in plug for my sink! He left the place spotless. This is the kind of service and installation people dream about - a 5 star service (see photos).
Posted on Google
Laura Peters
17 August 2026
Trustindex verifies that the original source of the review is Google.
I have used Comgas twice and both times have been very happy with the service. Very friendly and honest. The most recent time, the job turned out to be a lot bigger than they initially thought but it was no issue and Paul stayed the extra time to make sure the job was done properly! He was really tidy, took a lot of care with the work that was done and took the time to explain what he was doing and why. Pleased to have found a reliable heating company!
Posted on Google
James Ross
8 August 2026
Trustindex verifies that the original source of the review is Google.
I had an issue with my boiler and Matt came out to have a look the same day and managed to fix it. Great, professional service. Highly recommend.
Posted on Google
Ian Chevalier
11 June 2026
Trustindex verifies that the original source of the review is Google.
First time we've used this company and it won't be the last. Very professional and efficient in everything they do and Matt was excellent in his knowledge and efficiency when dealing with our gas and plumbing problems.
Posted on Google
Karen Flackett
20 May 2026
Trustindex verifies that the original source of the review is Google.
Excellent service. Matt came & fitted 2 taps & waste pipes he was polite & friendly & carried out the work efficiently & in a timely manner.
Posted on Google
Paul Norris
30 April 2026
Trustindex verifies that the original source of the review is Google.
Fantastic experience from the chaps at ComGas! Special thanks to Matt who removed an old boiler and replaced with a new energy efficient to satisfy the demands of a five bed house with a few bathrooms/baths and showers. The ComGas admin team and Lee were fantastic too on the booking and administration side of things!
Posted on Google
Julie Galvin
21 April 2026
Trustindex verifies that the original source of the review is Google.
Here at St Joseph's we have worked with Comgas for a number of years. They have completed big projects and undertake regular maintenance for our school. They price fairly, and their work is completed to a very high standard. All the engineers carry a DBS which makes life so much easier when trying to book an engineer visit.
On the rare occasion that we have an emergency I can trust that Lee will get one of his engineers to respond quickly and efficiently.
Nothing is too much trouble and no job is too small.
Posted on Google
Chesca Haley
16 April 2026
Trustindex verifies that the original source of the review is Google.
Lee and the team are amazing! So helpful, so knowledgeable and really look after their customers. Highly recommend.
Posted on Google
Sarah Rogers
6 April 2026
Trustindex verifies that the original source of the review is Google.
Absolutely amazing service, always a thorough job and very knowledgable. Really nice guys too. Lee has sorted numerous issues at work and around our house. We have recommended to friends and family who are also very happy
Posted on Google
Alison Molan
25 March 2026
Trustindex verifies that the original source of the review is Google.
Lovely engineers, Matt and Jack, were a pleasure to have in the house. Thorough, knowledgeable, tidy and polite. Would highly recommend.
Rewiring questions
Frequently asked questions.
If an inspection has flagged your wiring, or you're planning a renovation and want to know whether a rewire makes sense, get in touch and we'll assess it honestly.
Look for cloth or rubber-insulated cable, pre-2004 wiring colours, missing earth conductors on lighting circuits, or a report showing repeated significant findings across multiple circuits. A single faulty circuit or an old-looking consumer unit alone doesn't necessarily mean a full rewire is needed.
Can you rewire my house while I'm living in it?
Yes, this is common — we phase the work room by room or floor by floor and agree temporary power arrangements for areas out of action during their phase. The practical plan depends on the layout and how the household uses the space.
Will you make good the walls and redecorate after chasing cables?
No — we chase cable routes and fill them to a plasterable finish, but plastering, painting and final redecoration are outside our scope. We agree cable routes and outlet positions with you in advance so a decorator can plan around them afterwards.
What's the difference between a full rewire and a partial rewire?
A full rewire replaces the entire fixed electrical installation. A partial rewire addresses specific circuits, rooms or floors where the rest of the installation is genuinely sound, based on what a survey or inspection finds.
Does a rewire include a new consumer unit?
Typically yes, since a rewire is the natural point to bring the consumer unit up to current standards alongside the circuits it serves, though the two are technically separate pieces of work.
Can a rewire be combined with an extension or renovation project?
Yes, and it's often the most sensible time to do it. First-fix wiring is completed before plastering and sequenced with the wider building programme, with new circuits checked against the existing board's spare capacity.
How disruptive is a rewire in an occupied home?
It depends on the extent of the work and how it's phased. We plan access, temporary power and the order of rooms at survey stage so you know in advance what to expect from each phase.
