GEM ENVIRONMENTAL BUILDING SERVICES LIMITED
2.8(22)St James's, Westminster, London • NAPIT




Reviews
2.8
Some customers praise the business for punctual boiler servicing and leaving work areas clean. However, numerous reviews report long phone hold times, unreturned calls, missed appointments, and residents being left without heating or hot water for weeks. Additional complaints focus on engineers arriving without correct equipment, repairs causing leaks, and aggressive van driving.
Summarised with AI
Boiler service staff were brilliant turned up on time clean and tidy
Turned up on time great engineer left the house immaculate
I would take great care if you see these folks in a van - registration DN74 JFX. Deliberate close passing and then tailing aggressively. Wants to start a fight. Avoid.
Wish I could give 0 star. Worst contractor ever. To organise a visit I had to stay on hold for around an hour and often was put through to their call handling service who can’t do ANYTHING apart from promise a call back from the wider team. Never ever did I get a call back. Then when I did get an appointment, often they didnt show up. When they did come out they often didn’t come with the correct equipment and failed to fix it even though they claimed they did, which meant I had to go back to square 1 again with the infuriating process. Twice they made it worse so I got a leak so bad I had to replaster and repaint and hire a private contractor to do it urgently. Moreover times they offer are not possible if you work in person full time. Hated every minute interacting with GEM. So much energy put in to try and get the most simple things done. So glad Camden has moved contractor
If I could have given zero stars (or fewer?), I would have. Left me with no heating. Don’t turn up and don’t return calls. Thank goodness Camden have finally changed contractors. Avoid at all costs
Absolute disgrace of a company. If I could give zero stars I would. They have left my mum who’s a pensioner without heating for 6 weeks. No wonder they have lost the contract. Due to this they have completely given up, rude on the phone, dodged calls, broken promises to ring back. Multiple engineers have come out and we still don’t have a single clue what’s happening. You all should be ashamed.
Utterly ridiculous. 3+ months to change a radiator. Canceled the job 7 times. Left me without heat for the whole winter.
4 weeks with NO heating and NO hot water. This bunch manage the heating and hot water in my building. Their idea of managing a heating repair is to deliver a fan heater to the flat at 10pm then run away. We only looked outside when we thought someone was sniffing around the front door Camden should be ashamed of themselves paying good money to a bunch of cowboys. All the other negative reviews here are spot on, same experience from us.
AVOID Driver of van DN74 HXD almost collided with myself and other vehicles at a405/M1 junction (07:41 2nd December 2025) forcing onto slip road to skip traffic. Then almost crashed again forcing into lane 3 of the M1. Driver smoking in van also illegal.
GEM have got to be the worst company to deal with in terms of customer service.Persistence lies telling you we will call you back then wait a week before they decide to call and when a so called tradesman turns up no apology for waiting nearly two weeks for the repair not to be fixed and be told a load of nonsense by the tradesman this and that needs replacing then low and behold it doesn’t.There customer service staff don’t like being questioned about why GEM are such a terrible company they decide to cut you off truth hurts as they say. No wonder Camden council are ending there contract with this shoddy lot.
Disgusting example of how a company can operate. They shouldn't be allowed to run a company ! No service, no communication, no updates and you get stuck in a phone queue for hours and hours and then finally you get through to a call handling service who promise a call back within 4 hours but it never happens! They shouldn't be shut down ASAP!!!
This company is absolutely awful. I have had nothing but problems with them for years through camden council. Our heating and hot water for our block keeps going off and GEM lie and say they will send someone and when they do, they haven't a clue what they are doing! All my neighbours call up on the same day and they make out they don't know about the problem! We went though months of it going off every single day and having to call them out constantly. Eventually they put a new back up boiler in the communal room and it was okay until Sunday when it all went off again and I have been calling again non stop and all I get is lies! They just sent a man out to the boiler room and I just went to ask if he was any closer to finding out if he knew what was happening and the man was so rude! Just said I am busy and trying to do my work and didn't even turn around to look at me! Never had any of these problems when camden used BTU! If I could give them 0 stars I would! CAMDEN COUNCIL PLEASE BOYCOTT THIS COMPANY!!!
Great team to work with and some very talented people work here.
Excellent service - Thanks Gem!
It's a dissapointment that google doesn't allow to set 0 as a rating. Worst contractors you can even imaging: - advisors are lying to you about ETA - the requests to fix are always being ignored (it's 4 days already and 3 requests, none of them were resolved) - even if you request is being handled - the quality of work is awfull and only symptoms are being fixed, not a root cause - managers are always not on their place, I'm not sure they even exists - if you insist on fixing an issue, you will be blacklisted and won't be able to talk with advisors this company should be closed, they're just getting money for doing nothing!
The worst contractors that could ever be. The staff lie, they send contractors out for the wrong reasons and say parts are ordered when they’re not. The staff on the phone lines are RUDE. Especially Jenny her attitude is disgusting and it makes you feel like you’re an inconvenience when you’re a paying customer. All the staff do is sit in their vans or dance around the boilers. I made a complaint in April and no one got back to me. God knows how they’re still in business.
It is a shame that I am not allowed to leave a 0 to GEM as given them a 1 star rating is more than they deserve. Advisors promise to call back and never do. They are rude,lack of care and lie. They send two engineers with no parts within a hour space of eachother. How Camden have giving GEM a contract is beyond me. AVOID!
I have never been spoken to so rudely. They never accommodate you. They don’t explain that you need your own plumber on site. A nightmare to work with.
Avoid this company like a plaque! Job hasn't been done since last year's October!! Absolutely careless , unprofessional, don't know what they are doing, but most importantly liars - promise to call back , never does. Also lies that was at the site but doesn't show up. If you want to get things done - DO NOT HIRE THIS COMPANY
Gem have the contract with Westminster council . They promised to come on Friday to fix my heating , yet failed to turn up . The only decent engineer Kevin has left . I pay £80 per month for heat which I don’t have .
Location
Additional information
- Trading since 1999
- NAPIT
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