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NIA News – E-Brief : Welsh Government Approved Document L (Conservation of Fuel and Power, Volume 2: Buildings other than dwellings)

By October 10th, 2022No Comments

The Welsh Government has this week published a new set of Approved Documents on how to comply with Part L (Conservation of Fuel and Power) of the Building Regulations Act 2010. The NIA submitted an extensive response to its consultation which you can read here. The Approved Documents take effect in Wales on 29 March 2023 and provide practical guidance on how to comply with Part L of the Building Regulations, which are a legal requirement.

To read the building regulations, click here.

What standards are in place for insulation and thermal elements?

The new guidance raises the minimum energy efficiency requirements for individual thermal elements within buildings by setting out a range of maximum U-value requirements, which thermal elements in new or existing properties should adhere to.

The most significant changes come in the maximum U-value requirement for thermal elements in new buildings, which have been significantly tightened since the last iteration. Page 36 of the guidance sets out the maximum U-value requirements for different thermal elements in buildings. Furthermore, the Approved Documents stipulate that a new building must be built to a minimum standard of total energy performance.

The new guidance also includes some slight increases in the energy efficiency standards for new and replacement thermal elements in existing buildings.

What do the new standards say about renovated elements?

  • The updated guidance does not include any increase in energy efficiency standards for renovated thermal elements in existing buildings.
  • Thermal elements renovated in existing buildings should be improved to achieve or better the U-values set out on Page 40 of the Approved Documents.
  • Elements retained in existing buildings, for example following a material change of use or change to energy status, will only need to be upgraded to the improved U-values if they have a U-value higher than (worse than) the threshold value.

In our NIA consultation response, we pointed out the risk that stringent performance standards for new thermal elements in existing buildings “can lead to the creation of a disparity between new and existing thermal elements, resulting in unintended consequences, such as condensation and mould if not adequately managed.”

We are pleased that the Welsh Government has considered this, so that the Approved Documents make allowances for lesser standards if they are necessary, “in order to comply with Part C of the Building Regulations.”

In addition, the guidance states that, “insulation is expected to meet the improved U-value), subject to a moisture risk assessment”, therefore further addressing the NIA’s concerns.

Are there any trigger points for upgrading energy efficiency?

Another important aspect of the new Approved Documents is the introduction of numerous trigger points for upgrading the energy efficiency of thermal elements in existing buildings. These include:
  • When the renovation of thermal elements is being undertaken.
  • When the material use of a thermal element changes.
  • When the building has a change in energy status.

What are the Compliance Rules?

The Approved Documents also introduce tighter guidance regarding compliance, which the NIA welcomes.

In our NIA consultation response, we stressed the importance of introducing stricter guidance on compliance to close the performance gap and ensure that buildings perform as expected in the design stage, once constructed. We highlighted that, ‘Whilst inaccuracies in modelling can contribute to the performance gap, other factors such as poor construction practices can also lead to a building not performing as anticipated.’

We are pleased that these concerns are reflected in the Approved Documents. The guidance states that, “To demonstrate compliance with the energy efficiency requirements, the standardised Buildings Regulations UK Part L (BRUKL) report should be provided to the Building Control Body at design stage, and the as-constructed (BRUKL) report should be provided to the Building Control body and building owner at completion stage.” These reports can then be used by the Building Control Body check that what has been designed, is actually built.

The NIA agrees with the Welsh Government’s approach to ensure that the highest standards of energy efficiency and insulation are applied to buildings other than dwellings in Wales.

Why are the updated regulations beneficial for NIA members?

The Approved Documents make insulation an integral part of the Building Regulations in Wales. The guidance ensures that insulation is a key consideration, not just in new-build properties, but also when existing properties are renovated, or change their use. Therefore, the publication of this updated guidance represents an excellent opportunity for NIA members and the wider insulation industry to play a central role in the construction and renovation of buildings other than dwellings in Wales.

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