2. Planning and Design

In this chapter, we will discuss how building designers and urban planners make a significant contribution in the delivery of EFCS by incorporating new methods into their practices. This involves prioritising the reduction of waste and energy consumption through conscious material choices, efficient design strategies, and stakeholder collaboration.

WSP, ‘Net Zero Carbon Construction’. 2021. Accessed: Jan. 25, 2023. [Online]. Available: https://www.wsp.com/en-au/insights/net-zero-carbon-construction

Early-stage decision-making

Decisions made in the early stages often have the greatest impact on the final overall performance of the building. As a construction project evolves from an idea to planning and design, decisions are made that dictate the majority of embedded carbon in a building. Carbon emissions throughout the lifetime of the planned construction need to be taken into account. Consider how the decisions made will affect emissions at each stage of construction. Some actions to lower carbon emissions at the construction site are limited by design factors such as the choice of materials.

Main actors

The state and municipal administrations take the first steps in construction and infrastructure planning and therefore have immense potential to reduce emissions from construction sites. Authorities also have the opportunity to impose restrictions on emissions in general as well as to provide incentives.

Investors, property developers, and project owners play an important role. Decisions regarding low-impact construction are made at this level and these stakeholders set the course for designers.

The process

The process can roughly be divided into planning and design phases, starting with a conceptual stage and urban planning. At the conceptual stage, broad decisions are made regarding site selection, land use, and initial design concepts. This sets the framework for carbon reduction at a later stage. Urban planning involves integrating these projects into the broader context of a city, considering factors such as transportation, energy use, and earthworks.

Design, in this context, is considered as the development of individual structures and buildings. It involves detailed decisions about building materials, construction techniques, and systems that significantly influence a construction’s emissions. By prioritising the reduction of waste and material and energy consumption in design, significant reductions in emissions can be achieved.

Collaboration

Fostering collaboration among urban planners, developers, policymakers, and local communities to implement these guidelines effectively. By embracing these guidelines, urban planners can steer development initiatives towards EFCS.

2.1 Urban planning and infrastructure

Needs assessment

In the world of urban planning and infrastructure, every choice matters. Authorities must decide whether to build new or preserve what is already there. With sustainability in mind, it is worth considering that sometimes the best way to reduce emissions is simply not to build. So, before diving into new projects, it’s crucial to ask: Is it really necessary? If construction is unavoidable, let’s prioritise small, efficient designs. But let’s not forget what’s already available. Repurposing existing buildings can be a smart move. And let’s think about relocating businesses and homes to areas with empty buildings, breathing new life into forgotten spaces.

Location

The strategic selection of project locations is crucial, particularly with transportation efficiency in mind. Opt for locations where the transportation of earth/soil, building materials, machinery, and waste is over shorter distances. Moreover, choose areas where minimal earthworks are required due to favourable soil conditions and topography.

Infrastructure

If there are plans for using clean energy machinery during construction, ensuring the availability of clean energy sources from the outset of a construction project is necessary since time is valuable. Strategic location selection also involves prioritising accessibility to existing road infrastructure, electricity grids, water supply networks, and other essential utilities in order to minimise emissions from construction sites.

Urban planners should plan the order of infrastructure construction with this in mind. With an electricity grid and water supply network already in place, there is more potential to reduce energy consumption during construction, and temporary pipework can be avoided.

The power needed for charging electric machinery during construction can easily surpass the rating of the utility supply for the building. Electrical distribution and construction in the area can be scheduled so that power peaks are distributed evenly over time. This makes it necessary to find out the requirements related to the charging infrastructure of the construction sites.

Timing

Whenever feasible, construction activities should be scheduled to coincide with seasons that require minimal heating/cooling and lighting in order to reduce energy consumption, lower emissions, and enhance overall construction efficiency. This can save time, money, and emissions.

Waste management

Integrate waste management systems within urban planning frameworks. Allocate designated areas within project sites for sorting and storing construction and demolition waste (CDW) as well as for building material that is being stored on-site, facilitating the efficient separation and recycling of materials. By promoting circular economy principles, urban planners can minimise emissions from waste disposal and resource extraction.

Key points

Consider the necessity of the project and explore alternatives to a new building.
Select project locations strategically to minimise transportation distances and earthworks.
Ensure the availability of clean energy sources from the outset.
Plan the order of new infrastructure to ensure that essential utilities are in place from an early stage.
Schedule construction activities to coincide with the seasons to minimise the need for heating/cooling and lighting.
Allocate designated areas for sorting and storing building materials and waste.

2.2 Building materials

Prefabricated

Select building materials that result in minimal CDW, such as prefabricated elements, which can minimise on-site cutting and reduce reliance on large machinery. Prefabrication not only reduces material waste but also speeds up construction timelines and reduces energy consumption. Fewer machine hours mean fewer emissions. Prefabricated material that facilitates disassembly can also reduce emissions from machinery during demolition when the time comes. This also reduces waste during demolition since materials that are designed for disassembly are more likely to be reused.

Excess material and packaging

CDW can also be minimised by specifying exact material requirements when purchasing so as to minimise over-ordering and reduce packaging. Consult with suppliers to explore packaging alternatives that minimise waste without compromising product quality or safety. Additionally, negotiate with suppliers to establish protocols for the return of packaging, pallets, and excess materials, promoting a closed-loop system and further reducing waste generation.

Local material and communication

When selecting materials, prioritise local options to minimise transportation distances and associated emissions. This also reduces reliance on long-distance supply chains.
Maintaining good communication with those responsible for construction is crucial. A detailed set of project specifications is important in ensuring that the right materials are utilised as planned. Deviation from the specified materials can result in higher emissions and negate efforts to achieve emission-free objectives.^[13]

Key points

Select building materials that result in minimal waste and reduce energy consumption.
Use prefabricated components designed for disassembly in mind.
Specify exact material requirements.
Prioritise local materials.
Write a detailed project specification to ensure proper material use.

2.3 Excavated material

Construction and civil engineering projects often involve moving large amounts of excavated material in the form of soils and rocks. This process is both costly and energy-intensive, resulting in considerable emissions. Early-stage design and planning to avoid large-scale excavation and long-distance transportation of these materials are crucial for reducing emissions.

Mass disposal plan

A key strategy for minimising emissions is to incorporate a mass disposal plan early on in the project. The aim of such a plan should be to reduce the occurrence of excavation and the need for new raw materials and landfill usage. It should also focus on minimising the transportation of bulk materials. By planning how to reuse and recycle materials locally, emissions associated with transportation can be significantly reduced.

‘Hållbarhetskriterier för Schaktning och masshantering | Upphandlingsmyndigheten’. Accessed: Jul. 01, 2024. [Online]. Available: https://www.upphandlingsmyndigheten.se/kriterier/bygg-och-fastighet/schaktning-och-masshantering/

Avoid soil disturbance

Optimal sustainability in construction is achieved by maintaining existing natural ecosystem functions. At an early stage of project planning, consider how earthworks and construction can be adapted to avoid or reduce soil disturbance, excavation, and relocation. These practices help to minimise environmental impact and emissions.

CityLoops project

The CityLoops project, funded by the EU, provides guidelines for sustainable soil management and soil reuse assessment.

Cityloops, ‘Guidelines for Sustainable Soil Management and Assessment of Soil Reuse Potential of Excavated Soils’, Cityloops. Accessed: Jul. 01, 2024. [Online]. Available: cityloops.eu

Recommendations include evaluating alternative project locations and building designs to reduce soil excavation. Architectural considerations can also help minimise excavation needs. Exploring on-site or local reuse options for excavated soil – such as landscaping, noise reduction, biodiversity enhancement, climate mitigation, infrastructure, or recreational uses – can reduce transportation needs and associated emissions substantially.

Maximising on-site soil reuse should be a priority. Efforts should be focused on avoiding the transportation of soil to distant locations by identifying local reuse opportunities. Minimising excavation and utilising excess soil locally are effective strategies for reducing transportation emissions.

Key points

Develop and implement a mass disposal plan early on in the project.
Prioritise the local reuse and recycling of excavated materials.
Minimise the transportation of bulk materials through optimised design and planning.
Follow sustainable soil management guidelines to reduce environmental impact and emissions.