Lower carbon footprint with digital help

Photo: David Valldeby

Assembled CLT surface unit at Cederhusen on 12 January 2021. The building has served as a pilot project for reducing the carbon footprint using digital tools in the modelling stage.

ARTICLE Minimise the building’s carbon footprint on the drawing board. With advanced digital tools, it is possible to do a life cycle analysis and immediately see what effect different choices have on the building’s carbon footprint.

Conducting a life cycle analysis is nothing new, but to date that task has involved many steps and a lot of manual work, which is both long-winded and costly, states Anna Ervast Öberg, business and project development manager at Folkhem.
»It’s always been a laborious way of working, because the different programs couldn’t talk to each other, so we’ve had to manually extract the information we need. It gets expensive, and manual data entry creates the risk of errors, plus we don’t have a way of quality assuring the results.«
It is still the most common approach, but now the knowledge and tools exist to work in smarter ways. In conjunction with building the first wooden apartment block in the Cederhusen project in Hagastaden, Stockholm, Folkhem launched a collaborative project with engineering consultancy firm Bjerking to explore how the building’s carbon emissions could be reduced. In a digital life cycle analysis, they compared the data for four suppliers of wooden structural frames, and found that by choosing the supplier with the most energy-efficient production, they were able to halve the carbon footprint of the building, equating to a saving of 500 tonnes of carbon dioxide equivalents.
The program, One Click LCA, links up the design software for architects and structural engineers, for example, with information from the suppliers. This makes it possible to compare the carbon footprint of different materials and suppliers, directly within the design drawing.
»When the architect or structural engineer designs a 3D model, it links to the program, and when they make an adjustment in the design, they can see immediately how it affects the climate, the cost and so on,« explains Robert af Wetterstedt, sustainability specialist at Bjerking and coordinator of the project.
But, he adds, for it to function successfully, the whole industry needs to review how it
works digitally. Anna Ervast Öberg draws the
same conclusion:
»It’s all very well us having the tools to create wonderful 3D models that we then
pass on to the building contractor, but that’s no good if the material supplier comes along with a paper list – everyone in the process has to participate in the digitalisation process.«

To be able to compare materials, the information about them needs to follow the same standards and be studied on a detailed level. To ensure that the Swedish wood industry contributes to this, Swedish Wood has recently launched the web-based portal traprodukter.se, where each affiliated supplier adds their information in a standardised format. In this initial phase, orderers can visit the portal to access the information, but it will eventually be possible, via the app’s user interface, to connect with other programs and databases.
»Until now there has been no kind of standardisation, which means that the analysis results could vary wildly, depending on where you get the reference data from. Using precise data instead of estimates will make the calculations more reliable,« says Christer Green, project manager for digitalisation at
Swedish Wood.
Each item in the portal is given a unique identity or global trade item number (GTIN), which is the key to the unique information stored on each item. »With its unique ID, each item can be traced through its entire life cycle. In the future, you will be able to see exactly what materials are where in the building, and what their carbon footprint is,« says Christer.

The aim of the portal is in part to help improve construction productivity, but also to help construction industry players to produce accurate climate declarations. Certain buildings now have to have an energy declaration, and an increasing number of environmental certification schemes for buildings
– including Miljöbyggnad and BREEAM – require a life cycle analysis. Sweden’s environmental requirements will also become even more explicit on 1 January 2022. According to a bill developed by Boverket on behalf of the government, all new buildings that require planning permission must have a climate declaration from that date onwards.
»We expect the requirements to be tightened within a few years, so that climate impacts and performance will need to be stated in the declaration, and in 10 years’ time there’ll be threshold values that cannot be exceeded. That’s going to create a need for additional knowledge, technology and data systems,« says Robert af Wetterstedt.
Calculations from Boverket show that the cost of drawing up a climate declaration for a single-family house ranges from SEK 30,000– 60,000 (EUR 3,000–6,000). For larger properties, the cost may be higher, but an automated process can cut the cost significantly.

However, the main point is that digitalisation of the construction and real estate sector will enable it to reduce its emissions from the 12.8 million tonnes of carbon dioxide equivalents generated in 2016, according to Boverket, to the vision of zero net emissions by 2045. »To get our buildings to last longer, we must be fully on top of the materials. We need a better understanding of how we can optimise our projects in terms of the climate and how best to design the buildings. Producing data showing the carbon footprint enables us to make decisions at an early stage that are critical for the building’s sustainability,« says Anna Ervast Öberg.

Get news & inspiration from Swedish Wood

Sign up and get information about publications and other news from Swedish Wood by email.

Sign up for the newsletter