**1. Introduction**

Building construction and demolition industries are the largest contributors to overall waste among the other industries globally [1]. Due to the non-recyclability of building materials, almost 50% of the entire waste is generated by the construction industries [2]. In 2016, European member countries have generated 2.54 billion tons of waste which are expected to rise to 3.4 billion tons per year by 2050 [3]. The journal of the European Union [4] suggested a waste hierarchy to deal with materials in the following order: prevention, preparing for re-use, recycling, recovery and, finally, disposal. Moreover, European Commission (2018) prepared a protocol and guideline for waste management to implement circular economy.

Globally, the construction sector has been developing environmental burdens by consuming primary resources, and energy and producing a significant amount of waste [5]. This industry is accountable for 36% of CO2 emissions and 40% of total energy consumption in Europe [4]. As this sector is consuming a huge amount of primary resources, especially minerals, wood and ferrous metals, it is of utmost importance to figure out ways to minimize the consumption rate and impact on climate change [5]. Using recyclable materials and utilizing the building waste after demolition can help to reduce this burden and impact on our climate [5]. To increase the material values and use available resources in a circular material flow by recycling process, [6] proposed the concept of the circular economy (CE). Moreover, European Commission [4] prepared a protocol and guideline for waste management to

### *The Circular Economy - Recent Advances in Sustainable Waste Management*

**Figure 1.** *Energy use accountability of EE and OE [11].*

implement circular economy. Utilizing recovered building materials directly is more beneficial than recycling options as the reusing of building materials requires minimal energy usage than the recycling process [7]. Building deconstruction is preferable to the demolition process because of the economic and environmental benefits [8].

The alarming increase rate of building energy use and carbon emission has raised the issue to create new policies and strategies for sustainable and zero-energy building design and construction [9]. Energy-efficient buildings and constructions can change the energy use prospects in the coming decades and ensure the sustainability of the built environment [10]. Consequently, low-energy buildings can be one of the solutions to achieve the carbon reduction targets for the coming decades. But low energy buildings often use strategies like plastic insulation, energy-efficient service systems, and shading devices which reduce their operating energy demand at the expense of increasing the rate of embodied energy emission [11] (**Figure 1**).

Due to the high embodied carbon emission of low-energy buildings, the concept of reusing, and recycling building materials have been developed globally by many researchers to increase the resilience and durability of building materials. Building designers can contribute to minimizing the number of resources and materials used in construction by following the principles of circular economy [12]. Therefore, there are many scopes for researchers and designers to figure out the possibilities of designing low-energy buildings with lower embodied carbon emissions by reusing or recycling the same building materials or waste.

To address this issue, developing a material matrix will help to quantify the circularity of materials and enable the designers to be informed to prevent the harmful impact of the buildings on our environments [13]. Although the feasibility of circular economy may face several barriers like cost-effectiveness, quality, legislation and required time, this can contribute to protecting our natural resources and preventing global climate change.
