All high-rise boiler replacements are non-compliant with current Building Regulations, Ideal Boilers has warned. 

First reported by Inside Housing [paywall], a letter written by Dr Elaine Lancaster, Chief Technical Officer at Ideal Boilers, which was sent to a number of local authorities, raises concerns that high-rise boiler replacements are not compliant with newly amended Building Regulations.

The Building Regulations (Amendment) 2018, which was introduced in December last year in response to the Grenfell disaster, prohibited the use of combustible materials on the external walls of high-rise residential buildings, i.e. those above 18m tall.

The letter states that: "Ideal Boilers, along with all other leader manufacturers, currently provide a flue that comprises a steel painted outer air duct and internal polypropylene plastic inner flue duct. As the inner flue material is classed as a combustible material according to the standard, this type of flue can no longer be fitted to achieve compliance with Building Regulations."

Therefore, this effectively means that no boiler replacements in high-rise residential buildings comply with the Building Regulations at the present time.

Dr Elaine Lancaster goes on to say that although the current flue design means that the inner polypropylene plastic flue duct is well protected by the steel exterior, meaning that it is able to stop or hinder fire from reaching the outer skin of the exterior wall, it is still banned due to this new strict adoption of specific material classes.

She added the government department responsible for the regulation, the Ministry of Housing, Communities and Local Government (MHCLG), has started a review into the flue situation, but this could take "six to nine months". It is also unclear at this stage whether this would be a stay of execution or a permanent exemption, as is already in place for certain components including windows and doors.

The letter concludes: "The development of a new flue is technically not required and adds unnecessary burden and cost to the industry. It is not a route we want to take as we believe MHCLG should review the evidence and make existing flues exempt. However, we recognise that we must provide solutions to our customers to meet regulation. We are continuing to seek a sensible outcome to the current situation."