Figure 10.2 Circular Construction Actions

Figure 11.2Circular Construction Actions [12]

Specifically, this applies to contractors and manufacturers of key materials and building elements along with designers. If known, the end user and/or the building/estate management provider should also be engaged. This is especially important to determine the lifecycle implications of the design approach, for example:

➢ How the building will be maintained? ➢ What is the available budget? ➢ Is there an operational cost benefit from a circular approach?

Where possible, partnerships should be sought with integrated teams that have sustainability as a primary mission. Initial outcomes and objectives for the development should be revisited periodically through focused workshops and reviewed regularly at key stages.

Scarcity of resources and the need to reduce the environmental impacts of winning and processing construction materials and products is placing a greater emphasis on resource efficiency within the construction industry. It is estimated that the UK construction industry consumes some 400Mt of materials annually and generates some 120Mt of (construction, demolition and excavation) waste, of which 5Mt ends up in landfill. [17]. Therefore, there is significant scope for improving resource efficiency within the industry, particularly at the endof-life of buildings.

The benefits of recycling are well understood and include:

▪ Reducing waste, i.e. diverting waste from landfill ▪ Saving primary resources, i.e. substituting primary production ▪ Saving energy and associated greenhouse gas emissions through less energy intensive reprocessing.

Although these benefits apply to many commonly recycled materials, there are some important differences in the properties of materials that influence the environmental benefit of recycling and particularly how these benefits are quantified.

Metals, for example, are infinitely recyclable, i.e. they can be recycled again and again into functionally equivalent products - this is the most environmentally beneficial form of recycling.

Other products are ‘down-cycled’ into new products that are only suitable for lower grade applications because the recycled product has different, usually lower, material properties. Although waste is diverted from landfill by down-cycling, only lower grade primary resources are saved. For example crushing bricks and concrete for hardcore, sub-base or general fill saves aggregates but doesn’t save the resources required to make new bricks or new concrete.

For recycling to be sustainable in the long term, it is important that the recycling process is financially viable. This is frequently the biggest hurdle to recycling, particularly for products and materials that are down-cycled into lower grade, low value applications.

According to vand den Berg & Durmisevic [18] at this time of diminishing of resources and increase of environmental problems, it has become crucial to understand the capacities of buildings to transform a negative environmental impact of built environment to a positive one. The question is: how does one transform the current linear approach to design of buildings that has one ‘end-of-life’ option (demolition) to a circular design solution that will guarantee multiple life options of the building as well as of its systems, products and materials? Durmisevic has suggested that this can be achieved by systematically considering independence and exchangeability of building systems/components in three