In 2019, the UK Government became the first major economy in the world to pass laws to achieve net zero greenhouse gas emissions by 2050. It is therefore natural that we have seen an increased focus on carbon reduction in the construction market. In the last year or so we have seen an increase in the design and implementation of “zero carbon” projects and a greater emphasis on both embodied carbon and energy loss reductions.
The drive towards carbon reduction is a challenge for the construction industry as a whole, but it also has important direct implications for the Thermal Insulation industry. Many contractors will already be aware of a shift towards greater insulation thicknesses in building services specifications and that simply “quoting to BS 5422: 2023” will no longer be good enough for many forthcoming projects. There are a large number of specifications out in the market that stipulate thicknesses that exceed the requirements of BS 5422: 2023 and consultants are more mindful than ever about ensuring these additional criteria are met. One of the biggest drivers for these increased standards is the CIBSE CP1 Code of Practice for Heat Networks. An understanding of this document will be essential for those working in the residential market. This article will focus on this particular Code of Practice and explain how this is likely to affect the Thermal Insulation industry.
What is the Code of Practice and what is it trying to achieve?
Heat networks (or district heating schemes) supply heat from a central source to consumers, via a network of underground pipes carrying hot water. Heat networks can be city-wide or localised to a small cluster of buildings. As the UK looks to meet its net zero carbon commitments, use of heat networks is expected to grow rapidly – from meeting just 2% of the country’s heating needs in 2020 to 10% in the next ten years. CP1 is a voluntary code for secondary heat networks which sets minimum standards. The secondary heat network is classed as the system between the point of connection and the heat meter in each dwelling – essentially including all of the corridor and riser pipework that can contribute to overheating when inadequately insulated.
What does the Code of Practice say about pipe insulation?
The CIBSE CP1 Code of Practice, tables minimum insulation thicknesses for both phenolic insulation and mineral fibre insulation. Rather than taking the traditional method of stipulating insulation thicknesses based on W/M heat loss targets, the Code of Practice takes a broad-brush approach and stipulates a minimum thickness of insulation across all specified pipe sizes. CP1 advises a thickness of 50 mm pipe insulation for both phenolic and mineral fibre (with some increased thicknesses for mineral fibre on larger sized pipework). This minimum insulation table may lead to the expectation that systems insulated with either material will perform similarly. In practice, however, the thermal performance of these two materials is very different, and these minimums should not be considered in isolation. The main driving force behind insulation thickness will be the specific system performance criteria which needs to be met. As you may expect, this will vary from project to project. In some cases, this means that even these minimum thicknesses may not be sufficient. There may also be a significant gap in the energy performance of systems designed to these minimum requirements using these different insulants.
This of course means that deciding if an insulation system is going to be sufficient for the project at hand remains a complicated process. Thankfully, CP1 also pushes the consideration of detailed insulation specification into the early design process; for example output 3.9 (a,b,c) requires the insulation specification and calculations to be included at stage 3. There is also a requirement during stage 2 for the initial calculations to be kept on file.
What does this mean for thermal insulation going forward?
We are expecting CP1 to be adopted as the standard for many forthcoming residential developments, with the Governments’ intention being to make this a legal requirement in the coming years. We are also expecting some ESCo’s (Energy Services Companies) who own and operate these schemes to continue to stipulate thicknesses even exceeding those of CP1. Essentially, for the contractor every specification should be taken on its own merits and the cost implications clearly understood before a quotation is supplied. Kingspan Technical Insulation are of course here to support customers and our technical team are able to provide clarification of specification requirements and support via project specific calculations.
By working together as an industry, we can all play our part in ensuring that these new exacting standards are met, and that Thermal Insulation plays its part in the drive towards carbon reduction and a net zero carbon society.
Contact us
For CP1 pipe insulation thickness calculations please email us on: hvactechnical@kingspaninsulation.co.uk
CIBSE CP1 Code of Practice for Heat Networks – What does the new Code of Practice mean?
Download Technical Bulletin
Improving Heat Network Performance.
