Digitally crafted wood
KvalhoTalks with Katharina Lehmann | President of the Board of Directors of Blumer Lehmann AG
Welcome to KVALHO TALKS – a series of interviews and discussions with experts, innovators and entrepreneurs within the AEC & real estate industries. Our guests share with us how they use technology to create a competitive edge for their business, create value for their clients, deliver exciting projects and, importantly, move the industry forward. They also share their views on what's happening within the AEC industry today and what comes next.

We are delighted to talk to Katharina Lehmann, President of the Board of Directors of Blumer Lehmann AG, who shares with us her perspective on the digitalization of the construction industry. Blumer Lehman AG uses digital processes and impressive engineering skills of its team to design and manufacture geometrically complex free-form timber structures. Where timber constructions used to be limited to just a few floors, today thanks to digitalisation, designs are being drawn up for 30-storey high-rises. Residential, office and industrial buildings are bringing timber construction back to the urban environment, making timber the high-tech building material of the future.
Enjoy reading KvalhoTalks with Katharina and learn what role digitization plays in modern architecture and construction.


Could you give us a short overview of Blumer Lehmann and what is the core specialty of the company?
The whole company consists of 3 companies: sawmill (Lehmann Holzwerk AG), silos ( Blumer Lehmann Silobau AG) and timber construction (Blumer-Lehmann AG). We are 142 years old and employ approx. 300 skilled people. The company started with the sawmill established in 1875 which operated using a waterwheel. Our current focus is on developing timber in all its forms.
Blumer Lehmann is a family owned business with a long tradition. Reflecting on the past 10 years, how did the company adjust to digitization?
I believe the digitization in the timber sector has already started 20 years ago when we began the journey with prefabrication. We (the timber construction industry) were quite early as a building sector to use methods like CAD and 3D in our planning processes because it was required for prefabrication. Constant development of the IT in design and production processes allows us to now realise projects which were not possible before.
When was the time when you used the first computer controlled machine at your factory?
It was the Abbundmaschine for joinery by Hundegger in1988. The data from the simple CAD drawings was passed to the computer of the machine and elements of the structure were produced according to the drawings. In 2010, we bought the first 5-axis CNC machine (Computerized Numerical Control) ensuring precise production of double-curvature timber structures. This was when we won a contract for the Golf Club project in Yeoju, South Korea, designed by Shigeru Ban. It was just not possible to produce all the curved elements of the structure without the CNC technology.
How do you spot the market trends to keep innovating? Are market trends always clearly visible?
''They are never visible. Innovation means two things: 1. the good idea, and 2. is the realisation''.

Finding the idea is usually not that difficult but finding the courage to invest in this idea, believe in it and execute it is the real challenge. There is no simple recipe how to do it. Spotting market trends or opportunities is a process. When you have an idea which you believe in, you start reading about it, you talk to people, you start noticing things, you try to convince yourself that this is the right thing, the right way. And then you try to convince your own team too.
The innovation plays a large role at Blumer Lehmann. Is being innovative also a part of your company's strategy and the way to be ahead of a competition?
The strategy of the company is surviving. Surviving means also some kind of development. Standing still is not an option for us. Surviving has always an ambition of being modern, being up to date, having the best people, working with the best technology. That is probably the way the innovation starts.
Do you collaborate with Universities to develop new ideas and new technologies?
Yes, definitely. We work with universities on new ideas and we are learning from each other. We just did a project with EPFL IBOIS Théatre du Vidy in Lausanne and are also involved in the European project INNOCHAIN and projects of ETH, Zürich.
How do you find the best people ?
Challenging tasks and challenging projects are probably the most important things that attract people to come and work with us. And then we do our best to make them stay and we take care of all our team members. We hire highly skilled people and we engage them in the tasks where they can best use their competences. There is no specific school now for programming parametric codes into NC codes, therefore our employees develop their skills on the job and they put a significant effort into self- learning. Our employees need a combination of technical skills, knowledge of timber construction, IT skills and project management skills. There is no school which offers all of that.
What impact the digital fabrication of timber has on architecture?
Digital fabrication – it is a new language. It allows timber to be used and shown in different, new and fascinating ways. The fascination comes out of the combination of having the traditional material and using modern technologies to produce interesting shapes out of it. It's prefabrication as its best.
How does the whole concept of digital production help the design team?
We hear often about BIM but it seems like BIM is a word which is not understood properly. For us, it is a planning process where design team can communicate in one space on one model in an early stage, in more details, and as a team. What we are trying is not only seeing organised and concentrated planning processes, but we connect the design planning process to the production methods.

Do you run any education workshops for architects?
We are thinking about running a summer school next summer for international design teams.
What is the reaction of architects and clients who visit your factory for the first time and see how their projects are being produced by robots?
Pretty much every architect working on a project with us visits our factory right at the beginning of the project, because it is a part of the dialog between the design teams and Blumer Lehmann's team. We all work as a team. For an architect, it is always fascinating to see how their design is being produced. It is also important for the entire team to understand the possibilities or limitations of the production.
Which project was the most challenging to produce?
Every project produced on this CNC is challenging. Going new ways means facing issues which we never knew or believed need to be taken into consideration. You sit there and think: ''ok… that going to be a problem''. And then you talk to the team and try to find the way to solve it. But this should be done at a very early stage. You really have problems when you discover issues during production or in a late project phase. Developing, planning and generating the NC code its sometimes 24 Hr of work of solving issues.
Korea was our first challenging project to produce but after that, we also worked on spectacular objects like Swatch HQ in Switzerland. This project was huge – 230m long, consisting of 5000 building parts which needed to be produced on 4-5 machines at a time.

Everyone talks about Factory 4.0. What is it and what does it mean for Blumer Lehman?

We are not thinking about that. We know that in our industry and the entire building industry, we first need to automate and industrialise processes. This is the first step. And when we master this, we can then think about how to connect and use the data better.

Where do you think the digitization takes us by 2025? How do you see the construction industry developing ?

It will be automated, industrialised and there will be more prefabrication.

INTERVIEW BY JOANNA DEMKOW-BARTLOMÉ