Infrastructure Sustainability Ratings: Design vs As Built

Getting the best out of IS ratings

Seeing an infrastructure project come to fruition and start benefiting communities is rewarding. At Losee Consulting, this is especially so when we see the realisation of sustainability initiatives that began in design phase and see their way through construction to commissioning and operation.

The IS Rating Scheme evaluates sustainability initiatives and potential environmental, social and economic impacts of infrastructure projects and assets across their whole ‘useful’ lives, which can be as long as 100 years.

Project teams use the outcomes of the IS Rating Scheme, among many things, to unlock infrastructure’s potential beyond traditional value markers such as congestion reduction on roads.

When undertaking an IS Rating under version 1.2 or 2.2, projects assess performance during either the design phase or construction phase. The Design rating is superseded by the As Built rating. This arrangement means that project can publicise their intended performance with a certified Design rating, but they must follow through on their intentions in construction to obtain the permanent, As Built rating.

Different Infrastructure Sustainability Accredited Professionals (ISAP) or assessors may be undertaking these ratings separately, but in many cases they deliver them side by side, with construction commencing while design continues. With a strong focus on delivering essential infrastructure cost-effectively, project teams increasingly discuss the value of sustainability assessments, such as IS Ratings, and need to understand how best to apply each assessment.

Understanding the difference between an IS Design Rating and an IS As Built Rating, delivered during the construction phase of a project, helps project teams get the best out of each phase. As a small consultancy firm, Losee Consulting has experience at all levels with a variety of skill backgrounds, including Scott Losee, who has been actively involved since the inception of the rating scheme in Australia and New Zealand. Losee Consulting helps projects adapt systems to align with the rating being undertaken. We have broken down where project teams should focus during each key project stage below.

Emphasis during the design phase

During the design phase, project teams develop concept designs to a point that provides sufficient detail for confirming constructability and delivery within a set budget. This includes identifying environmental, social and economic impacts and opportunities. Unfortunately, teams can overlook these opportunities while prioritising efforts to develop the design to fit standards and budget.

Undertaking a sustainability assessment at this stage allows asset owners to use the industry-developed IS rating tool to benchmark decisions to determine what is compliant and what elements are providing enhancements across sustainability’s quadruple bottom line.

This stage gives project stakeholders an opportunity to assess design decisions against an industry framework, challenge design processes and look for better outcomes.

Certified design ratings give project teams and asset owners something to celebrate while the project is still being delivered, as well as setting clear expectations for delivery. A Design rating is the provisional rating as projects progress towards the implementation of the detailed design. When a project achieves a Design rating, teams should highlight where they have achieved sustainability outcomes and where they have identified improved outcomes for the construction or operation phases.

As Built phase implementation

The construction phase, on the other hand, gives project teams an opportunity to take the systems identified during design and implement them to go beyond best practice. By shifting focus from modelling outcomes in design to monitoring actual performance against those models, project teams can adjust focus areas and manage sustainability outcomes. The construction phase also gives teams an opportunity to refine modelling and planning from the design phase when they can achieve stronger outcomes. An independent review of these processes can challenge a project team and lead to better outcomes.

Value of specialist consultants

Asset owners, design consultants and construction contractors’ approach IS Ratings in different ways at each stage. Specialist consultants like Losee Consulting have the advantage of working with a variety of asset owners, designers and contractors. The independent perspective we can provide offers a productive challenge to how teams deliver assets. When done well, knowledge and skills are passed to delivery partners, improving future project sustainability and potentially reducing reliance on external consultants.