Two landlord companies have been fined for gas safety breaches at a block of privately rented flats in Hampstead, North London.

Valbond Management Ltd and sister company Holbond Ltd were prosecuted on 19 March by the Health & Safety Executive (HSE) after an investigation found that vital gas checks had been neglected, meaning faults were missed.

Westminster Magistrates’ Court heard that a Gas Safe registered engineer found a flue joint that had come apart in a ceiling void at one flat, managed by Valbond, that could have been leaking emissions from the boiler for as long as five years.

HSE’s investigation also found that two further properties in the block, one managed by Valbond and one by Holbond, also had gas boilers and concealed flue pipes that were not maintained.

Neither company had arranged annual gas safety inspections for the properties, as required by law, nor had landlord gas safety certificates been issued.

Magistrates were told that the tenants of the property where the leak occurred had left, as they had no confidence in Valbond’s ability to manage the gas system to ensure they were safe.

Valbond Management Ltd and Holbond Ltd, both registered at Shelley Stock Hutter LLP in Chandos Street, London W1, pleaded guilty to two charges each under the Gas Safety (Installation and Use) Regulations 1998. Valbond was fined a total of £28,000 with £432 in costs and Holbond was fined a total of £20,000 with £432 in costs.

HSE inspector James Caren said: “It was by chance, not the action of Valbond, that the boiler at the flat was working efficiently and not releasing high levels of carbon monoxide. Such releases can be particularly dangerous where people sleep, such as domestic flats.

“Landlords have an absolute duty to ensure the gas systems at their properties are safe so they do not put their tenants at risk. They have a similar duty to have them checked by a Gas Safe registered engineer every year. Both Valbond and Holbond fell well below acceptable standards.”