Home   /   Services   /  Compliance & Rating Systems   /  NABERS / Design for Performance

NABERS / Design for Performance

NABERS is a six-star rating system that measures the actual energy use of buildings once they are in operation. The scheme been used in Australia for the past two decades, and has since been adapted by other countries, including New Zealand and the UK, wishing to emulate the success of the Australian performance-based ratings system. 

IES has long supported a modelling beyond compliance approach to eliminate performance gaps and our consulting team collectively draw from hundreds of man years of experience in this area to help achieve the optimum performance outcomes for our clients.  We have all the required tools and ‘Design for Performance’ expertise to help you to undertake these projects and begin to move into a more performance-based design world. 


The launch of NABERS UK in November 2020 marked an important turning point for the UK buildings industry where, historically, a “design for compliance” approach has largely been the norm. 

Our team can support you in pursuing your desired NABERS rating as your building progresses through the RIBA stages, continually refining the simulation and building energy assessment.

Currently, NABERS UK offers two products: 

•    NABERS Energy Ratings 
•    Design for Performance (DfP)

NABERS Energy ratings measure and verify the recorded energy use of existing offices, helping building owners to accurately track and communicate the energy performance of their buildings. 

Meanwhile, Design for Performance (DfP) provides a framework for developers to help ensure their projects deliver against their design expectations, helping to embed energy performance targets within the delivery supply chain and providing checks and assurance measures to help achieve the targeted performance rating in operation. 

The objective of using DfP at the design stage is to more accurately estimate the energy consumption by simulating the refurbished office space as it is expected to operate, using best practice inputs and principles. 

Concept & Design

At this stage, we can support you by developing a DSM model, taking into consideration all of your base building energy loads, including whole building HVAC and all energy used in the common parts including lights, small power, lifts, external lighting, dedicated car parks, standby generators, etc., which currently fall within the scope of NABERS UK assessments.

When conducting a design stage NABERS UK assessment, we can help you study a whole range of ‘Off-Axis’ scenarios which must be investigated to illustrate your building’s resilience to real-world performance risks. 

Examples of Off-Axis scenarios which our team can help you incorporate into the modelled design for NABERS UK assessment may include (but are not limited to): 

  • Weather (impact of climate change) 
  • Building Operation (impact in occupying the building for longer/shorter periods) 
  • Occupancy (uncertainty/future changes in occupancy – particularly relevant in light of COVID-19) 
  • Other miscellaneous loads (i.e. potential increases in Equipment loads) 

Handover & In-Use

At this stage, IES Consulting can:

  • Develop a Digital Twin of the operational building 
  • Use data from BMS to improve accuracy of model variables and close performance gap 
  • Aid engineers in considering design improvements and refurbishment options via your calibrated model

Improve HVAC Performance at every stage of the building life cycle

IES Consulting are perfectly placed to take your model to the next level in HVAC performance. We can represent and then refine your design by reporting on plant sizing, load matching and overall energy/carbon performance, a crucial step in achieving your desired NABERS rating.

Related Projects

Latest work from our consultancy team