Scottish Building Standards 2015 – Overview of the Domestic New Build requirements

Scottish boy with the flag of Scotland

The Scottish government have released the 2015 building standards 12 months ahead of their implementation (October 2015) in order to allow the house building industry plenty of time to get to grips with the new requirements; this blog post considers the changes to new build domestic requirements…

Both domestic and non domestic standards are available at:

http://www.scotland.gov.uk/Topics/Built-Environment/Building/Building-standards/techbooks/s62015

The 2015 edition of Section 6 incorporates a number of changes whilst retaining the existing methodology introduced in 2007. The majority of these changes relate to improvement in specified performance to deliver the intended 21% aggregate reduction in carbon dioxide emissions on the 2010 standards (45% when compared to 2007 standards).

  • Standard 6.1 – SAP 2012  now used to calculate carbon dioxide emissions; both changes to methodology and revised carbon factors for fuels apply
  • Comprehensive revisions of fuel package table and associated notes to deliver 21% aggregate improvement on 2010 CO2 emissions
  • Improved fabric backstops for new buildings
  • Revisions to calculation of heat loss from linear thermal bridging
  • Improved fabric backstops for extensions, option to consider improvements to existing dwelling when subject to ‘column (a)’ U-values; example provided in Annex 6B
  • Reference is now made to the Domestic Building Services Compliance Guide for Scotland for detailed guidance in support of each standard; any situations not addressed in this document are noted within the
    guidance to the relevant standard e.g. where very low infiltration rates proposed
  • Provision of ‘quick start guide’ now applies to all new dwellings.

For new build dwellings, the simplified compliance target setting packages are as follows:

Gas Package

LPG Package

Oil Package

Electric Package

Floor

0.15

0.15

0.15

0.15

Walls

0.17

0.17

0.17

0.17

Roof

0.11

0.11

0.11

0.11

Windows & Doors

1.40 (0.63 g-value)

1.40 (0.63 g-value)

1.40 (0.63 g-value)

1.40 (0.63 g-value)

Air tightness

7.0

7.0

7.0

7.0

Other Key stuff:

89%+ efficient gas boiler

Very good heating controls

Waste Water Heat Recovery

Photovoltaics

89%+ efficient LPG boiler

Very good heating controls

Wood Log Burner

Waste Water Heat Recovery

Photovoltaics

90%+ efficient oil boiler

Very good heating controls

Wood Log Burner

Waste Water Heat Recovery

Photovoltaics

Air to Water Heat Pump (175.1%+)

 Good heating controls

Waste Water Heat Recovery

The Biomass (86%+ efficiency) package also comes out fairly well, with no PV requirement, but otherwise similar to the electric one.

For those packages with a Photovoltaics requirement, the target is based on 0.01 x dwelling total floor area, which equates to a maximum of around 30% of roof area.

All the above are also based on:

  • 100% low energy lighting
  • Fully filled or solid party walls
  • Fully insulated primary pipework
  • Natural ventilation
  • thermal bridging target not tightened (0.08 x total exposed surface area)

Obviously the actual dwelling can vary from the above, but for the fabric, limiting area weighted U-values have also been tightened as follows:

Area weighted average U-value limit Individual element Limiting U-value 
Roof   (W/m²K) 0.15 0.35
External Wall (W/m²K) 0.22 0.70
Floors (W/m²K) 0.18 0.70
Windows, doors and rooflights (W/m²K) 1.60 3.30
Party   Walls 0.20
Figure   1: Limiting Backstop Fabric Parameters 

The electric package has got off a little easy, but then the Scottish Government is committed to decarbonising the grid much more quickly than the rest of the UK.

Overall there’s nothing unexpected and the standards are a good step forward for the building fabric – reducing heating demand is the obvious best step to reducing emissions and fuel bills.

To keep up to date with all our latest blog posts you can follow the blog by clicking this RSS Feed link or by following us on Twitter @KingspanIns_UK or on Linkedin.

Share this blog post with your friends and colleagues by clicking on the social media icons below.

Print this page
About

Jon Ducker is a qualified energy assessor working for Kingspan Insulation Ltd. He has an extensive knowledge of energy efficiency, renewable energy systems and sustainability in buildings with an expert knowledge of the relevant sections of buildings regulations and standards and their interactions with SAP. He provides authoritative advice regarding energy assessments for a wide range of public and private sector clients.

Leave a Reply

Your email address will not be published. Required fields are marked *