Today, with increasing environmental awareness and the global need to reduce greenhouse gas (GHG) emissions, sustainable buildings are becoming a priority for the construction industry [1]. For this reason, it is possible to calculate the carbon footprint of buildings, which is an important tool for assessing the impact of their design and construction on climate change ^[2][3][2,3].

This scientific publication is focused on the study of the carbon footprint of single-family houses. The carbon footprint includes the emissions of carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), ozone, and other GHGs emitted during the entire life cycle of a building, from its design and construction phase through operation to the end of its life. The measure of a carbon footprint is one kilogram of carbon dioxide equivalent (CO₂e). Different GHGs contribute to global warming in different ways, and the carbon dioxide equivalent allows emissions of different gases to be compared on a common scale. This allows us to compare different building solutions, whole structures, and technologies to choose those with the lowest CO₂e emissions. Buildings are estimated to be responsible for up to 40% of global CO₂e emissions ^[4][5][4,5]. The aim of this research is to understand the impact of the different stages of a building’s life cycle and the impact of the building’s structural elements on its carbon footprint and to compare masonry and timber-frame construction in terms of their impact on GHG emissions. In the context of building design and construction, the study of a building’s carbon footprint becomes very important as emissions are still at high levels and the construction sector is not on a path to decarbonisation by 2050 [6]. Firstly, reducing GHG emissions is necessary to mitigate climate change and protect the natural environment [7]. As the construction sector is one of the main sources of these emissions, it is particularly important to adopt an environmentally friendly and sustainable approach to the design and construction of residential buildings [8]. Secondly, a carbon footprint study provides an opportunity to compare different design solutions in terms of their impact on GHG emissions [9]. In the case of residential buildings, the comparison between masonry and timber-frame construction is particularly important, as differences in building materials and manufacturing processes can lead to significant differences in the carbon footprint. Finally, there is an economic dimension to analysing the carbon footprint of the design and construction of residential buildings ^[10][11][10,11]. A growing number of investors and developers are recognising that buildings with a low carbon footprint can be a source of long-term financial savings through reduced operating costs and energy consumption [12].

The construction of a sustainable future requires meticulous attention to the materials and practises utilised in the building sector, where both masonry and wood constructions have been widely adopted but are controversial due to their respective impacts on the environment ^[13][14][15][13,14,15]. This research emerges from a need to comprehend and contrast the carbon footprints of buildings constructed from these materials, located within the context of a holistic Life Cycle Assessment (LCA) integrated with Building Information Modeling (BIM) technology. A detailed exploration of existing studies reveals a diverse landscape of research in the domain of sustainable building materials ^[16][17][18][16,17,18]. For example, Kylili and Fokaides [19] assert that sustainable development of the built environment will arise from a greater use of alternative, recycled, natural, and unconventional construction and insulation materials, the use of prefabricated building elements, and the integration of LCA with BIM. Meanwhile, numerous contemporary studies highlight the possibilities of using BIM to reduce the overall environmental impact of a building, especially emphasising its practicality in the early design phases ^[20][21][22][20,21,22]. However, there still exists a gap in merging these domains, particularly in delivering a comprehensive comparative analysis between timber and masonry constructions through a unified LCA approach integrated with BIM. Wood as a building material can play a key role in transitioning to a more sustainable and less emission-intensive economic sector [23]. Responsible forestry, grounded in principles of sustainable development that allow for the perpetual renewal of forest resources, is paramount [24]. Inappropriate timber harvesting practices harm biodiversity and contribute to deforestation [25].

Several frameworks and methodologies have been developed to calculate the carbon footprint of buildings. The most popular methods include (i) standards, (ii) LCA, and (iii) a dedicated computer software tool.

Assessments are based on ISO 14040 [26] and ISO 14044 [27] standards, which are the key standards for LCA and are commonly used to measure the carbon footprint of buildings and building materials [28]. The LCA method is a comprehensive research method that considers all stages of a building’s life cycle, from raw material sourcing to production, construction, usage, and destruction ^[29][30][29,30]. The basic elements of LCA are (1) the identification and quantitative assessment of the environmental impacts, i.e., the materials and energy consumed and the emissions and waste released into the environment; (2) the assessment of the potential consequences of these impacts; and (3) the evaluation of the options available to reduce the impacts. The LCA method is widely used in the study of the carbon footprint of buildings due to its holistic approach and the consideration of many aspects of the building (Table 1) ^[31][32][33][31,32,33].

The range of tools available, including OpenLCA, SimaPro + Report Maker, Tally (GaBi), Umberto LCA+, and OneClickLCA Product Carbon & EPD Generator, provides users with different options to choose from based on both project requirements and user preferences. Although this variety ostensibly facilitates a thorough analysis of the carbon footprint of buildings, which is a crucial element given the current sustainability and environmental challenges, it is imperative to dive deeper into the efficacy and limitations of each tool to validate its results and applicability. A nuanced evaluation that acknowledges both the advantages and disadvantages of these tools is essential to ensure accuracy and reliability in their application. Although several market offerings allow analysis to be performed in a professional and competent manner, there is a notable limitation in their functionality for building designers. It is therefore imperative to critically analyse the need for an advanced tool that enables assessment at the design and decision stage, possibly integrating BIM, whilst ensuring the accuracy and validity of its results.

The carbon footprint and LCA of buildings in the design process could be examined using BIM technology, which is both scientifically justified ^[40][41][40,41] and very practical ^[42][43][42,43]. BIM offers a comprehensive solution by integrating building information into a central model, creating a ‘digital twin’ of the building that is under design ^[44][45][44,45]. In the area of carbon footprint assessment, BIM programme facilitates the handling of data on building materials used in project designs. These data play a crucial role in the accurate calculation of carbon emissions. It takes into account the manufacture, transport, and installation of building materials ^[46][47][46,47]. By using BIM programme to design building elements with appropriate materials, it is possible to precisely monitor the influence of individual building design components on the entire carbon footprint of the building.

As a result of increased attention in the field, there are now an increased number of tools available on the market for computing a structure’s carbon footprint. The most accurate and efficient tools are those that are developed based on a high-precision 3D model of the structure, established using BIM technology ^[48][49][48,49]. Integration of these tools enables users to import data from the BIM model, including building geometry, material information, and energy consumption. This feature allows for a comprehensive carbon footprint analysis ^[50][51][52][50,51,52]. Using BIM programme, it becomes possible to consider all pertinent factors that impact GHG emissions throughout the life of a building. In addition, BIM programme also offers energy simulation tools to account for energy consumption in the building ^[53][54][53,54]. Simulations provide data on the GHG emissions related to heating, lighting, cooling, and ventilation, facilitating the evaluation of a building’s carbon footprint with respect to its operation. An essential benefit of BIM programme is its ability to enable teamwork with different design and construction crews on a project. In this way, objective information on materials, energy consumption, and GHG emissions can be collected and updated in real time. Through ongoing data analysis, it is possible to identify the areas that have the greatest impact on carbon footprint, allowing a strategic reduction plan to be developed ^[55][56][55,56].

The use of BIM programme to calculate the carbon footprint of buildings is not only scientifically reliable but also pragmatic. It offers sophisticated tools for data collection, analysis, and visualisation, facilitating a deeper understanding of the impact of individual elements on carbon footprint. This enables informed design and construction decisions to minimise GHG emissions (Table 2).