He also took the time to talk about HIU repairs versus replacement even outside office hours.

Bob C from Isle of Dogs East London – E14. ( 11th of May )
Wow!! Add Detail delivered exceptional service resulting in a very positive experience and total peace of mind. Highly professional, extremely competent and proactive. "Can do attitude" with a smile. My HIU had been leaking since Christmas and had not been serviced in many years. I was concerned that the HIU wasn't fixable and that a costly replacement HIU was the only option. Justin looked at the leak and fixed it without any fuss. He was also proactive and did extra work and checks to make sure the job was finished to a very high standard. He also took the time to talk about HIU repairs versus replacement even outside office hours. I will be recommending Add Detail to my Estate Management Company so other residents in my building can use them for HIU repairs/replacement/annual service.

Danfoss HIU valve replacement.

Rollo C. from Dalston, North London – N1 ( 19th of May. )
Add Detail did a great job replacing 7 values on my HIU. Justin was helpful and super easy and straightforward to deal with. I would definitely recommend.

Highly recommend this firm.

James O, from Poplar East London – E14. ( 25th of May. )
Excellent service from the first point of contact. Very flexible when I wanted to change dates which they accommodated as I had a fairly urgent problem. The workmanship was excellent as was the follow up visit to fit the new parts needed to repair my HIU. The job was completed quickly with the minimum of fuss and no mess. Highly recommend this firm.

HIU Service

We offer an end-to-end HIU servicing solution, ensuring your system is running at optimum efficiency saving you time and money

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HIU Repair

All our London based HIU repair specialists are highly equipped to diagnose faults quickly and on the first visit, saving you time and money

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All HIU Services

All HIU Services including repair, maintenance, replacement & installation, emergency service and group booking options.

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HIU Contract Maintenance Services

Add Detail has over 15 years of rich experience in the commercial heating industry and in offering end-to-end HIU solutions.

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 We install gas cookers, perform gas leak detection and gas safety tests.

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Heating & Boilers

Services include repairing leaks to full heating system installations,  full boiler installation, service and repair.

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Our services include hanging doors. replacing or installing skirting boards, wood panelling and bespoke fitted furniture.

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Services range from fixing leaks and clearing blocked pipes, to shower pump repairs and complete bathroom suite installtion

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HIU Engineers, Gas & Heating Engineers, Plumbers and Carpenters in London and surrounding areas

Add Detail are able to provide HIU engineers, plumbers, heating engineers, gas safety engineers & boiler installations, electricians and carpenters to residential properties across London.

The dedicated team of craftsmen at Add Detail work around the clock to ensure that every piece of work, whether it be an emergency plumbing job or HIU repair or service, is completed to exceptional standards that they are proud of.

Our team whether they be HIU engineers, plumbers, carpenters, gas or boiler engineers, all live and work in London, and therefore both know the area intimately, and, are never more than a stone’s throw away should you need their support.


Need something fixing? Looking to improve you home? We will get back to you within 24 hours.



To find out more about our services or to discuss your requirements, get in touch.