New and existing non-domestic buildings

New and existing non-domestic buildings

Pilkington Glazing at Slimming World
Through its consultation ending on 15th October 2021, the Scottish Government has set out its proposed changes to Section 6 (Energy) of the Technical Handbooks for domestic and non-domestic buildings.

For new non-domestic buildings, the consultation sets out two options to uplift energy efficiency standards in 2022 as follows:
Option  Reduction in carbon emissions (compared with 2015 standard) 
1
(medium)
16%
2
(high)
25%

There are proposed changes to the maximum U values for fabric elements for new non-domestic buildings.  However, the expectation is that the U value will have to be much lower than this to enable new buildings to achieve the Target Primary Energy Rate (TPER).  The notional building specification used to determine the TPER is based on the following U values of fenestration elements:
Element  U value (W/m2K)
Option 1
(medium)
Option 2
(high)
Windows 1.4 0.9
Rooflights 1.5 1.5

In the notional building specification, the g value of the glazing is stated as 0.29, indicating that glass with higher solar control performance (lower g value) than at present may be needed.

The maximum U value for fenestration elements of non-domestic buildings (including extensions and existing buildings) are summarised below:
 
Element U value (W/m2K)
Option 1
(medium)
Option 2
(high)
Windows and roof windows 1.6 1.2
Rooflights 2.1 1.9
Pedestrian doors 1.4 1.0

Notes:
  1. U values for rooflights should be calculated on the horizontal plane
  2. There is no maximum U value for display windows (e.g. shopfronts), although their impact must be taken into account in the calculation for the new building
The consultation documents can be found here.

To satisfy the above requirements, Pilkington provides a range of low-e glass that can provide thermal insulation.

Where a low g value is required, Pilkington provides a range of solar control glass for reducing solar gains in buildings, while maintaining high levels of daylight.

If you have any questions on changes and what the implications might be for glass, please complete our online contact form, selecting 'Architect' or 'Trade' as the Nature of Enquiry and 'Other' as the Enquiry Type. Please state 'Technical Handbook Section 6' in the Question / Comment box when completing the form.