Why timber is better than building law thinks it is

Timber Construction 2020

✅ We have developed the building systems and engineered all necessary functions and safety dimensions. We know how it's done. Safely.

❓ What is holding us back?

👉🏼 Most building codes and regulations that timber buildings are subject to have been passed in a time, where timber was not yet the high-tech engineered-to-excellence product it is now. Yet, these regulations define not only how we can build, but also what we can build – and what we can't.


In the last decades, the number of multi-storey timber buildings has been increasing constantly. It is striking though, how these buildings are not spread out evenly across the European Union, but pooled in certain regions.

While of course there are multiple reasons to this, unequal timber-related regulation-sets have a strong influence.


For timber specialist and lecturer at TU Graz (AT), Tom Kaden, this is the main problem:

Building codes do not reflect the technical and technological possibilities of modern timber construction.

🎥 Watch the full interview with Tom Kaden on YouTube.



Build-in-Wood: Comparing national building regulations

Even though we have harmonised requirements on how to declare the product performances at building material/component levels EU-wide, our national requirements at building level are not harmonised.

This poses a challenge to anyone trying to compare inter-country regulations or even has construction business in various countries.


At Build-in-Wood, we are enhancing available data with results of our own research. Three main areas of focus are fire protection, acoustic performance and energy consumption. It is our goal to provide the gathered data to everyone in an open access format. 👉🏼 Go to Zenodo to get the data.

👉🏼 We are grateful for anyone willing to provide input or suggest improvements to the data handling: Please reach out to Peder Fynholm (pfy@dti.dk).


Timber buildings and fire resistance

Fire regulations, just like most other regulations, vary from country to country. Dionysis Kolaitis, researcher and Technical Director of the "Fire Engineering Unit" at the National Technical University of Athens, explains:

"Fire burns the same way everywhere. However, the fire safety concepts and the fire-fighting strategies differ between countries."

Of course the safety of anyone in or next to the building needs to be guaranteed the same way and to similar standards anywhere - but both resources and expectations vary:

  • Is it acceptable for the house to burn down completely?

  • For how long does the structural frame need to resist fire?

  • How far away is the next fire brigade and how long does it take for them to get there?

  • What do the surroundings look like - urban or rural?

Graph of selected European Countries and how long their regulations want timber buildings of certain heights to withstand fire (range 30-180mins)
Comparison: Minutes of required fire resistance in selected European Countries

The graphic by our Consortium partner Waugh Thistleton Architects clearly illustrates how different fire related regulations are throughout certain EU countries.



How regulations restrict our construction sectors

While investors, engineers and architects play a leading role in the structuring and design of a building, outdated building codes often severely restricted them. These codes vary greatly - on a global level of course, but also between the Member States of the European Union.

➡️ If in one country, you have to go through meticulous documentation processes, or pay huge amounts of money for special permits, while in another country, regulations are more timber-friendly and building permits are obtained easily, it is not surprising, that we do not find equal numbers of taller timber buildings between European states.

Peder Fynholm, Technical Manager of Build-in-Wood and Vice Director "Wood and Biomaterials" at Danish Technological Institute in Copenhagen relates this to a lack of experience and understanding of characteristics and capability of timber construction in building authorities:

If you’re not sure how to deal with this, it’s easier just to say no. The knowledge gaps are the critical part.

In line with the illustration above, Tom Kaden points out how difficult it is in Germany to build “four or five storeys” in timber. In Switzerland, on the other hand, the building law is very permissive, allowing multi-storey timber buildings rather easily. This is not because the Swiss don’t care as much about human safety, well-being and energy consumption – they sure do!

But their building law is simply more aware of all the solutions to these issues that nowadays are used in European timber construction.



Building regulations: our areas of focus

Our regulation-collection focusses on two levels:

  1. General overview of EU member state regulations (e.g. national annexes and guidelines)

  2. Specific legislation (e.g. codes for multi-storey wood buildings in countries of our Early Adopter Cities).

We examine the seven central requirements for construction works (legislations passed by the Construction Product Regulation (CPR) and covered by all member states). Additionally, we target specific legislations for selected areas of importance for multi-storey wood buildings (focus on loadbearing structure) have been collected and presented in spreadsheets for the areas mentioned above:

  • Fire protection

  • Acoustic performance

  • Energy consumption

⤵️ You can download these overviews (excel) on Zenodo.