Design for life
Good design takes resource scarcity into account. And the reuse of materials by combining new technology and creative thinking is a cornerstone of design optimisation. Innovative technological advances and intensified knowledge-sharing between architects, engineers and customers will make reducing, recycling and reusing materials easier and more cost-effective, according to Lars Ostenfeld Riemann, Group Market Director of Buildings at Ramboll:
- We’re constantly seeking innovative solutions and sustainable products that offer higher coefficients of utilization and enable us to extend the lifetime of a building or an area with a minimum of resources. Sometimes it’s a matter of optimising the form of a building to a more efficient shape, or suggesting alternative materials for a better and more sustainable design that ensures materials are decomposed and then recycled, he says.
As part of this industry, the Ramboll Computational Design team in the UK works solely on using digital intelligence to create more optimised, buildable and sustainable structures than would have been possible using traditional engineering techniques.
For the Milan Expo 2015, architects designed the Vanke Pavilion with more than 100 different types of tiles in a highly complex, curved design that cost a great deal to produce. Advanced techniques with computational design made it possible to generate the layout and reduce the number of tiles to just five different types, a solution that significantly lowered project costs.
Flexible design extends lifetime of buildings
Optimising resources also means looking at design with fresh eyes. A building should be designed with a flexibility that, if needed, lets it be transformed for other functions. To this end, the design should include several disassembly strategies.
- If we design every building with more than one purpose in mind, we extend its lifetime. Take sports arenas, for example. In the past, sports arenas were built with limited functionality in mind, for instance an ice hockey rink or a football field. But today we build multi-arenas that can be transformed for many different purposes, whether indoor or outdoor sports, concerts, fairs or other events. So, instead of building several venues for different purposes, we only need to build one highly flexible facility, explains Lars Ostenfeld Riemann.
Let lifetime analysis determine choice of materials
Whether a project involves building a brand-new facility or refurbishing an existing one, a key consideration is to determine how to use more recycled building materials to save resources. Performing a lifetime analysis of the building project and its functions is the best strategy for making this determination and actually seeing the project from a different perspective.
- Recycling building materials requires that the various components can be easily disassembled. From a socioeconomic standpoint, recycling all materials can be a costly affair, especially in cases involving chemicals or other non-recyclable components like the PCB embedded in cement-based products. Analysing the lifetime expectancy of the specific project helps us choose the materials best-suited for each function, explains Hanne Tine Ring Hansen, PhD and Sustainability Expert at Ramboll.
In the Nordic countries, the expected lifetime of buildings is usually more than 75 years. The load-bearing structures of the building must be built in a very robust material like concrete or steel, while other elements of the building, such as the building envelope, can be constructed in materials with low environmental impact or a high degree of recyclable content, such as wood, steel, and glass.
Insulation materials should be organic because windows and insulation have to be replaced after about 30 years. Technological developments mean that building installations usually have a life expectancy of 10 to 15 years.
According to Hanne Tine Ring Hansen, the way forward is to increase methodological awareness and learn from international certification practices such as Cradle to Cradle, LEED, BREEAM and DGNB.
Technological breakthrough for minimising steel use
While steel remains a preferred material for structures, it is still an expensive resource. In the quest for a way to limit the amount of expensive reinforcement steel used to carry structural loads, Ramboll has spearheaded a technological breakthrough in the construction industry, developing a software tool designed to optimise design with millions of design parameters. The tool is especially suited for calculating pre-cast concrete structures.
- The tool will help us calculate concrete structures with much more refinement than today. This will ultimately help minimise the amount of reinforcement steel needed in most building projects, thus contributing to a more sustainable building process as well as lowering production costs, explains Kasper Paaske Larsen, PhD and Structural Engineer, Ramboll.
The software is based on well-known construction theories, but with the computer power available today and the wide range of parameters integrated, the team was able to develop the first commercially viable method, expected to be ready by the end of 2015.