“Karl has carried out an amazing refurbishment for us, and 'It looks so different but feels so right'. It involved knocking a wall down and inserting a steel, putting in a patio door, moving the consumer unit, gas meter and internal water stop cock. He has been professional throughout and attention to detail is second to none. We had a few issues to overcome on our journey, but Karl listened and everything was sorted out to achieve the desired effect. Throughout the project he has at all times tried to ensure we could continue to live in our home with the least amount of disruption and at the end of each day tidied up the area. We now have a beautiful 'space' which we both love being in. Thank you Karl”
Public evidence profile · Checked June 2026
K C F I Plumbing & Heating
Credentials & registries
Which? Trusted Trader
Trust Score
48out of 100
- Rated 5.0 from 21 reviews
- Reviewed 12 months ago
How this score is worked out
Rating5.0 / 5
Review volumeLow · 21
Independent sources1 independent public source
Credentials1 credential shown
How this score is made up
What customers say29.3 of 60
Independent checks8.8 of 30
Track record10 of 10
See the independent checks
- Licences and credentials0.6 of 8.3
- Ways to reach them8.3 of 8.3
- Reviewed on more than one site0 of 6.2
- Registered company details0 of 4.1
- Photos of their work0 of 2.1
- Industry recognition0 of 1
Missing evidence lowers the score because we can't check it. It doesn't mean it doesn't exist. Claiming a profile never changes the score. Evidence context, not a guarantee of workmanship.
Trust at a glance
1 checkWhat we can verify about K C F I Plumbing & Heating
Each card sums up one thing we can check from public sources. Open it for the full detail and the named source. This is evidence context, not a guarantee.
See the full verification checklist for K C F I Plumbing & Heating →Reviews · public evidence
What customers say
These reviews are published independently on the named public source below, not testimonials this business chose to show. We bring them together and link each one back to where it appeared, so you can open the source and read it yourself.
5.0out of 5
Customers often mention
Where these reviews are published
- Which? Trusted Traders21 reviews · 5.0 avg
Highlights
“Karl recently carried out a complete renovation of our bathroom. It is refreshing to find someone who really takes a pride in their work. We found that someone in Karl. Any problems were overcome with skilful thoroughness - this is not a man who will cut corners just to get the work done. The end result is a bathroom with a showroom like finish for which we cannot thank Karl enough.”
“KCFI Plumbing cannot recommend highly enough, attention to detail professional polite and very tidy and reliable. If your looking for a refurb on a kitchen or bathroom then Karl is your man Results are amazing Thanks Karl Carol and John”
Detailed reviews
These are the individual reviews we hold for K C F I Plumbing & Heating, including the highlights above. The 21 headline total is the review volume reported across public review sources.
Kitchen/Dining Room/Utility Room Refurbishment
Karl has carried out an amazing refurbishment for us, and 'It looks so different but feels so right'. It involved knocking a wall down and inserting a steel, putting in a patio door, moving the consumer unit, gas meter and internal water stop cock. He has been professional throughout and attention to detail is second to none. We had a few issues to overcome on our journey, but Karl listened and everything was sorted out to achieve the desired effect. Throughout the project he has at all times tried to ensure we could continue to live in our home with the least amount of disruption and at the end of each day tidied up the area. We now have a beautiful 'space' which we both love being in. Thank you Karl
Bathroom renovation
Karl recently carried out a complete renovation of our bathroom. It is refreshing to find someone who really takes a pride in their work. We found that someone in Karl. Any problems were overcome with skilful thoroughness - this is not a man who will cut corners just to get the work done. The end result is a bathroom with a showroom like finish for which we cannot thank Karl enough.
Refit Bathroom
KCFI Plumbing cannot recommend highly enough, attention to detail professional polite and very tidy and reliable. If your looking for a refurb on a kitchen or bathroom then Karl is your man Results are amazing Thanks Karl Carol and John
Wet Room to Luxury Ensuite
We inherited a poorly constructed wet room from the previous owners of our new home. Karl inspected the job and we received a competitive quote and agreed a start date. He also suggested trade suppliers for the sanitaryware etc which in our opinion is a superior quality to the high-street as well as cost effective pricing. On dismantling the wet room, it became clear extra work was needed which we agreed to. The job understandably took longer than first estimated, however the result is a bathroom worthy of being on the front page of House & Garden! Karl by his own admission is a perfectionist, he’s also very friendly, was great with our cheeky Spaniel and a tidy worker – we have absolutely no hesitation in recommending him and his work.
Kitchen doors replacement
From the initial survey visit, to assess the work, through to completion, Karl (and Brad) provided an excellent service. They were professional and diligent in carrying out the works and finding solutions to the inevitable issues that arise during such works. They were very clean and tidy, clearing up at the end of each day. Both Karl and Brad are extremely personable and we would highly recommend KCFI without hesitation.
Read the other 15 detailed reviews on this pageShow fewer reviews
Excellent Plumber
Karl came to refit the house radiators this week. He was efficient, tidy and did an excellent job. He was able to accomodate our specific needs easily and was really thoughtful - going above and beyond to ensure we were ok with the installation. I would recommend him without hesitation.
Amazing refurbishment!
Karl has done a fantastic job refurbishing my very old and outdated kitchen which including removing a wall and installing patio doors. From start to finish I have found Karl very easy to deal with, he is professional, friendly, patient and considerate. His work is always very clean and tidy and completed to a very high standard. I have been kept up to date with progress and additional work has always been discussed and agreed with me in advance. I can thoroughly recommend Karl, my new kitchen is perfect!
Bathroom renovation
Karl did a fantastic job on my bathroom renovation fitting a new shower, sink, toilet, flooring and painting, needed ripping out some extra work done as well. A* finish to a very high standard, highly recommend, amazing service and very courteous as well. Very well priced as well and stuck to the timescale and always informed and updated while the work was being done as I was away. No issues at all after work either.
Excellent Job
Karl did an excellent job replacing a damaged ceramic hob in our kitchen. I would thoroughly recommend him.
Amazing job
Really happy with the service. Would 100 percent recommend to a friend.
Excellent Job
Fitted a new shower unit and toilet pan. He did a fantastic job paying great attention to detail. This is the second time we have used Karl and I wouldn't hesitate to call him for any future jobs.
Excellent job! Will certainly recommend.
A first class craftsman. His attention to detail was second to none. Excellent service from start to finish. Real pleased with work carried out & end result.
First class job
This was a small but not straightforward job and Karl expertly made modifications which resulted in a perfect finish.
First class job
Although mine was a small job it was not as straightforward as first seemed. Karl expertly modified the fitting resulting in a perfect result.
Our dream bathroom
Karl did a fantastic job, great attention to detail, feels like he really cared about creating the bathroom we envisioned. Tidy and considerate worker. Great advice and communication with us throughout the project. Highly, highly recommend.
Excellent job
Excellent job. Careful worker with attention to detail. Would certainly recommend him.
Good service
Prompt response when required, good professional service.
Very skilled and considerate.
Karl has done a fantastic job. He worked very hard, kept me informed throughout and he is a perfectionist! Our bathroom looks great, and we will definitely call him for any future jobs.
Vision now reality
Delighted with my new bathroom, it is exactly what I wanted. The work took longer than estimated but the quality of finish is superb. Karl was excellent to deal with and I have no hesitation in recommending him. He took the vision I had of my new bathroom and made it real, perfectly.
Professional and reliable
Attention to detail was 1st class. Entirely trustworthy. Upfront about additional costs.
Local context
Rated 5.0, above the local average for plumbers in Welwyn Garden City
Across 11 plumbers in Welwyn Garden City, the typical rating is 4.7 out of 5. We compare against the same businesses a homeowner would find searching for this trade locally.
Credentials and associations
1Credentials and memberships
These credentials and memberships are attributed to named public sources. Check the source before relying on them.
- Source checked
- 25 Jun 2026
Source-listed gallery
21 photosPhotos listed on Which? Trusted Traders
These sources do not label every image as completed work. The gallery may include projects, people, logos or certificates, so it does not count as completed-work evidence.
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From Which? Trusted Traders
Opening hours
The hours this business publishes online, handy for knowing when to call. Confirm before you set off.
- Monday–Friday
- 8:30am–6:30pm
Sources
1 named public sourceWhere this information comes from
Everything on this page is drawn from named public sources. Where a source provides a public link, you can open the original and dig deeper.
Review sources
Public evidence last checked June 2026
About
Premium Bathroom & Kitchen Installation - My name is Karl and I'm a professional bathroom and kitchen installer and qualified plumber based in Hertfordshire, United Kingdom, with more than 25 years experience, and a Which? Trusted Trader. No matter what your budget or size of the project I provide a complete and courteous service from start to finish with all aspects of a project managed and completed. You can see some examples of my work in my gallery and browse just a few of the projects I've completed. If you like what you see, give me a call or use the contact form on my website to send me a message. - My services: - Bathroom Design & Installation - Kitchen Design & Installation - En-Suites - Wet Rooms - Disabled Suites - Tiling - Decorating - Supplied & Fitted or Fit Only Complete, professional service from start to finish.
Services they list
Bathroom design servicesBathroom refurbishmentBathroom suppliersWet roomsAccessible bathrooms and showersKitchen installationKitchen designKitchen refurbishmenten-suite fittingunderfloor heating
Listed on public sources or the business's own website; check directly that they cover your job before you book.
What this business says about itself
From their own website
What this business says about itself
See their work: Photo gallery (opens in new tab) · Facebook (opens in new tab)
Accreditations it displays. Confirm each is current on the official register before you hire:
- Which? Trusted Trader · verify (opens in new tab) · we hold this registration
These are statements the business makes on its own website, worth confirming in writing (and on the official registers) before you hire, not independently verified by us.
Your own checks
What to check before you hire
Worth checking yourself
Only a few public reviews are shown. Ask for recent references you can contact.
Their public evidence comes from a single source. Look them up on another site before deciding.
Verify at the sourceCheck them yourself
Approved plumbers on the free WaterSafe register are vetted, qualified to the water regulations and insured. Check they're listed, or find a WaterSafe-approved plumber near you.
Check the WaterSafe registerAgree the call-out fee, the hourly or fixed rate, and whether parts are charged on top, in writing, before an emergency plumber starts. Out-of-hours overcharging and 'while I'm here' add-ons are common complaints.
Be wary of a plumber who, on a first visit, says your whole system or boiler must be replaced. Get a second opinion and an itemised quote (parts and labour separately) before agreeing to major work.
Gas and boiler work is a separate, regulated trade, not general plumbing. Make sure anyone working on a gas appliance is specifically registered to do gas work, and ask to see that registration before they start.
Want an extra legitimacy check? Run the Cowboy Checker on K C F I Plumbing & Heating before you contact them.
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Common questions about K C F I Plumbing & Heating
Is K C F I Plumbing & Heating a legitimate business?
K C F I Plumbing & Heating has 21 independent public reviews, rated 5 out of 5. This is independent public evidence gathered from named public sources (no ads, no paid placement), not a guarantee of workmanship. If anything here is out of date, the business can request a correction.
What do customers say about K C F I Plumbing & Heating?
K C F I Plumbing & Heating has 21 public reviews, averaging 5 out of 5. You can read the individual reviews and where each came from in the reviews section above.
How do I know K C F I Plumbing & Heating's reviews are genuine?
K C F I Plumbing & Heating's 21 public reviews come from a named public review source, and MyTrustedTraders links every one back to where it was published, so you can open the source and read them yourself rather than trusting a single curated page. MyTrustedTraders brings this public evidence together with no ads and no paid placement: we show where every review came from rather than selling rankings, so you can weigh the evidence for yourself.
Is K C F I Plumbing & Heating qualified and accredited?
We hold 1 independently sourced credential for K C F I Plumbing & Heating, including Which? Trusted Trader. Each is attributed to the body that issued it in the credentials section. For example, Which? Trusted Trader is Which? Trusted Trader: an endorsement from the consumer champion Which?, given to traders who pass its assessment process.
What does K C F I Plumbing & Heating specialise in?
K C F I Plumbing & Heating lists specialist services including Bathroom design services, Bathroom refurbishment, Bathroom suppliers, Wet rooms, Accessible bathrooms and showers, Kitchen installation. If your job is one of these, look for it in their listed services or ask them to confirm for your project.
How long has K C F I Plumbing & Heating been trading?
K C F I Plumbing & Heating has been reviewed on public sources since 2015.