New Dynamic Simulation Modelling Guide major step-change to creating net-zero public buildings in Scotland

Date Published

28th Jan 2022

Colin Rees
LCEA, LEED AP
Divisional Head of Consultancy, Global

As part of the new Net Zero Public Sector Buildings (NZPSB) Standard, commissioned by Scottish Futures Trust (SFT), IES Consulting are proud to have written and developed a new Dynamic Simulation Modelling guide that will support building designers in meeting the requirements of the Standard.

This Standard supports public bodies to meet their net zero commitments for their new build and major refurbishment projects. The Standard, which can be adopted on a voluntary basis, has a central principle of verification to ensure the project goals are achieved.

Following approval of the Standard by Ministers in November 2020, a suite of supporting documentation has been published to provide public bodies with the tools necessary to apply the Standard to their projects. The Dynamic Simulation Modelling guide forms part of this suite to support reporting against the Operational Energy Target and Net Zero Carbon performance.

The Scottish Government’s Standard was developed by the Net Zero team at the Scottish Futures Trust in collaboration with Zero Waste Scotland and Health Facilities Scotland (part of NHS National Services Scotland) with input from across the construction and public sectors in Scotland.

The modelling guide developed by IES signals a step change to the way modelling has been previously performed on public sector buildings in Scotland. It is a significant step forward in terms of modelling detail and project stakeholder collaboration that is required to support zero carbon building design predictions which are then verified in use. 

Dynamic Simulation Modelling involves the entire project team, so everyone involved in the design, construction and management of the building inputs knowledge into the building model, not just the Mechanical Engineers.

The guide describes procedures for Dynamic Simulation Modelling and reporting directly mapped to the RIBA Plan of Work stages 0-7. The guidance ranges from the early concept design right through to the ‘post-occupancy’ operational stage. 

The approach aspires to move the sector away from traditional ‘modelling for compliance’ approach whereby models are simply created to pass Building Regulations.  Modelling within the Scottish construction sector has historically focused on plant sizing for mechanical building services, and achieving compliance with Section 6 of Scottish Building Standards, using relatively simple simulation approaches, such as steady state heat loss/heat gains calculations and the ‘Simplified Building Energy Model’ (SBEM). This approach has contributed to a perceived ‘performance gap’ between the predictions of energy provided by designers at the design stage of a building when compared to its performance in use. The Dynamic Simulation Modelling provided in this guide will take a significant step forward in closing this performance gap by adopting a comprehensive and detailed approach to building systems analysis, known as ‘HVAC’ modelling, to calculate the ‘Operational Energy Target’ predictions.

The modelling guide, whilst primarily aimed at Dynamic Simulation Modelling modellers, is also written to inform all project stakeholders in understanding how to obtain the right level of Dynamic Simulation Modelling to make the necessary evidence-based decisions to meet both the Operational Energy Target (OET) as well as Indoor Environmental Quality (IEQ) objectives for their project.

As part of the NZPSB standard, an Operational Energy Target (OET) is set out at the beginning of the project. Delivering the OET may be linked to public sector funding for the project, such that in order to receive full funding the project would be expected to meet the energy measured in use. The Dynamic Simulation Modelling guide supports project teams to perform the detailed modelling required to ensure their projects meet the operational energy targets. 

The Standard includes reference to 10 Pathfinder projects, the intention was to review their performance to the Standard’s objectives.  IES performed detailed modelling for three projects to support the OET and IEQ objectives. IES have a played a key role on the University Hospital Monklands supporting NHS Lanarkshire and the design team on the ambitious operational energy target toward the goal of a Net Zero Carbon hospital. In partnership with East Ayrshire Council, IES carried out modelling for Dunlop Early Learning Campus, which was pursuing Passivhaus accreditation, and St Sophia’s Primary School, which was pursuing an Enerphit certification. 

The operational targets set by the Standard will always be challenging and to be successful a radical reduction in operational energy use from pre-existing levels will be required. Central to achieving this is enhanced modelling where the model metering and real building meters/sub-meters exactly align and there is a focus on verification though post occupancy Measurement and Verification (M&V). 

To fulfil Net Zero Carbon building targets IES will be able to assist with the vital upskilling of designers that is required to enable the necessary level of modelling. IES has the technology and expertise to help those involved in the design and management of buildings to achieve their net zero targets. Through its technology, consulting services and training IES can ensure you have the necessary competence and analysis to meet your targets at every stage of the process.

For more information please contact our consulting team.

Latest from DiscoverIES