1. Introduction

This report on future research needs for emission-free construction sites describes the Work Package 4 (WP4) perspective on the future of construction with respect to reducing the climate impact from the transport of materials and construction installation. We describe the solutions that we have identified as being necessary and that are in the process of being implemented in projects, where there is a need for improvement and where technological innovation and policy support are needed.

Understanding which barriers are hampering the developments that are needed and finding solutions to them is crucial for reducing greenhouse gas emissions from construction sites. In addition to emissions from the production of materials, construction site emissions include upfront emissions that need to be addressed now. In contrast, other emissions can be influenced over a building’s lifetime.

Some of the solutions come up against systematic barriers which prevent them from being used in projects. Organisations and processes in construction do not traditionally consider greenhouse gas emissions as an important parameter. Emissions reductions based on system-level solutions can be very cost-effective.

Market conditions often limit the feasibility of new solutions. Cost is usually the dominant factor determining the choice of a material or process. New alternatives need to be deliverable at a competitive cost if they are to become widely used.

Stakeholders can decide to use a less carbon-intensive product, material, or process as an alternative to a conventional solution. Such decisions are preferably based on research or experience.

The construction sector is taking a more conservative approach due to the risks and consequences of buildings and infrastructure not functioning as planned. Research and pilot projects can be used to minimise the risks and uncertainties involved in using new methods and tools.

The focus on emissions from construction processes and the construction site itself is fairly recent and many questions remain unanswered. A knowledge base is gradually being established across the Nordic countries. More research is needed if we’re to accelerate the reduction in emissions. This report aims to identify areas where more knowledge is needed in relation to emission reductions on construction sites.

The previously published report "Emission-free Construction Sites: Definitions, Boundaries, and Terminology – Current Status in the Nordic Countries" (Ólafsson, Steingrímsdóttir, and Einarsdóttir 2023), describes the status in the field and is used to identify barriers and needs for further innovation and research.

Based on the previous work, the field has been divided into the following key areas for emission reductions on construction sites:

For this report, stakeholders in the Nordic construction industry were asked for their input on barriers and gaps in knowledge in relation to emission-free construction. A literature review of current research was then conducted, and information was gathered on innovative new construction technologies. This has resulted in a list of current research needs that funding bodies should give special attention to. Each chapter starts with a summary of the main research recommendations.