It can be tempting to switch off when the conversation turns to BIM and how it could solve yet another major construction industry challenge – the wonders of Building Information Modelling have sometimes proved to be a mirage with the much lauded productivity gains often falling short of expectations.
These days many architects associate BIM with a somewhat cumbersome way of creating 3D models, for the benefits of quicker drawing extraction, scheduling, change management and for the more adventurous, collaborative working. Few have taken advantage of the original idea of BIM – the ability to tag a database of properties to 3D ‘objects’, which then allows reporting on these interactively at any point during a building’s lifecycle.
Yet when it comes to resource efficiency, the solutions are all about being clever with large datasets and knowing what data to tag and extract for what purpose. Energy, water and waste are relatively simple indicators but there are a broad range of factors contributing to these, which vary throughout a building’s lifecycle.
In the absence of a standardised core set of indicators, building, product and material properties that contribute to resource consumption need to be drawn together on a case by case basis from disparate sources – EPCs, energy models, drawings, log books, O&M manuals, energy bills, valuation office data, sustainability certification (BREEAM, LEED…), various embodied carbon databases, etc.
Expensive as that is for now, tracking and benchmarking just a few parameters of a project, at least from design to operation, has proved to be worthwhile on pilot projects, such as AHR’s Pool and Tremough Innovation Centres and Bath & North East Somerset Council Offices in Keynsham. In fact tracking just energy use and key contributing factors seem to result in surprising gains in productivity and a design that is likely to be more resilient to changes in climate and occupancy.
In developing the design team’s approach to deliver Bath & North East Somerset Council’s new offices, the UK’s first DEC A rated office building, AHR instigated the use of an ‘energy risk register’, which tags every major building element that contributes to the targeted outstanding operational performance. The same process was repeated for embodied carbon. This has resulted in a much more streamlined and effective way of delivering the client’s requirements with greater collaboration in the exact areas that ‘Soft Landings’ is keen to enforce, without the need to sign up for BREEAM or any other detailed sustainability standard.
This process could become much more cost-effective by adopting an agreed industry standard for extracting data on building properties and components relating to building performance. A BIM classification system that provides the framework for tagging and reporting properties such as U values, thermal bridging, airtightness, exposed surface area, floor to floor heights, system efficiency, building zoning, embodied carbon, water consumption, etc. would make life a great deal easier for manufacturers, designers, contractors and building operators. The ability to review these alongside embodied and operational energy use figures would allow stakeholders at key lifecycle stages to focus on factors that matter when it comes to resource efficiency.
Are we chasing yet another BIM mirage? Perhaps, but with RIBA Enterprises, the lead party in the consortium to develop the classification system for the implementation of BIM 2 in the UK, we might be in for a pleasant surprise. No pressure NBS!
Judit Kimpian is Director of Sustainable Architecture and Research at AHR.
23 APRIL 2015