Explore

Back to knowledge

Construction and Buildings: optimal management of waste at the end of building life cycle

Currently, at the end of a building’s life the majority of its materials are sent to landfill or down-cycled into products of much lower value. To maximize the recovery and valorisation potential of existing materials in buildings and minimize waste in construction, optimal waste management at the end of life of buildings is essential. The right treatment and disposal of materials at the end of life can significantly reduce the construction sector’s environmental footprint. 

 

There are several approaches to better manage materials from demolition of buildings: 

 

Urban mining – the process of recovering and reusing a city’s materials – can offer a viable solution to improve waste management in the construction sector. The aim is also to increase the value of waste, so that recovered materials can be used in applications similar to those for which they were originally designed

Using the recovered materials for new building projects has environmental advantages. By keeping the materials in the city/district, long supply chains can be prevented and emissions thereby reduced. Urban mining also limits the demand for new building materials, which in turn reduces greenhouse gas emissions. 

 

Building phases (BAMB project) [6] 

Urban mining can be facilitated by the use of material passports, which offer information about the types of materials present in a building. Material passports were successfully piloted in BAMB, where material passports where used in designing and constructing a new office building [11]. The use of innovative technology-enabled solutions can further facilitate the recovery of used materials, such as the BIM-based “smart pre-demolition audits and waste management” tested in the HISER project [13]. 

 

In addition, designing buildings for deconstruction and reuse allows better access to materials at the end-of-life of a component or a building. Design for de-construction or disassembly (i.e., a reverse construction process) allows the building to be de-constructed as much as possible, without damaging the remaining functional parts and components [BAMB]. This increases potential for renovation and reduces landfill waste [Houseful]. The design should allow simple disassembly and preferably avoid multiple types of structural systems [12]. In designing for reuse, a BIM (Building Information Model) can be a useful digital tool to store the information for the lifecycle of the building. For instance, the design for re-use was piloted in BAMB and in Houseful. 

 

Life cycle of building [5] 

Lease contracts and buy-back agreements for materials encourage recycling and re-use of materials. Suppliers conclude a contract with the buyers, committing to eventually buy back the product. The benefit for buyers lies in overall reduced prices; for the suppliers, the material flow for recycling is guaranteed. The lease contracts are still in early piloting phase. 

MATURITY:  

 

Examples of solutions that are already available: 

  • Cradle-to-Cradle® certified products were used in Venlo City Hall in the Netherlands. The lease contracts and buy-back agreements with suppliers were typically 15-25% of the original prices, for office furniture and indoor finishing. Overall, a 10% residual value was estimated for the building in 40 years and the bank has reduced mortgage interest accordingly [BAMB][7].   

  • In a hospital renovation in Sweden, the use of circular materials increased the costs of only 0.33%, compared to the investment that would have been necessary if non-circular materials were used. Additionally, the maintenance costs are estimated to be lower [BAMB]. 

 

Demonstration stage: 

  • The demonstrated dismantling process includes the selection of safety procedures for disassembly and reuse of non-hazardous materials in construction elements, aiming to achieve a potential reduction of 30% in CDW (Construction and Demolition Waste) currently produced during building dismantling/demolition [Houseful]. 

  • Different renovation options were demonstrated in 4RinEU. A cost-effectiveness rating system explains the level of risks and failures in the renovation chain, allowing different stakeholders (e.g. investors) to evaluate risk of investment, responsibilities, achievable performance results and relative uncertainty, as well as related costs. The aim is to decrease primary energy consumption by 60-70% [8]. 

  • Following a demonstration in London, CIRCUIT produced a guide for sourcing the reclaimed construction materials, helping to use the reclaimed materials in new construction developments. The guide was produced with project partners to help practitioners in the real-life projects [9]. 

 

Comments ()

Tags

Circular economyWasteBuildingMaterialsTechnology
Under license CC BY-NC-SA
This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format for noncommercial purposes only, and only so long as attribution is given to the creator. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.