One of the fields that has been struck by these myths and bias most is by no means the building industry. We have asked Ing. Jan Řezáč, the CEO of the Wood for Life Foundation, to explain some of them to us. Wooden houses account for less than one percent of the total annual construction in the Czech Republic, while in Austria and Germany it is between 10 to 15 %, in the USA 60 %, and in Canada and Scandinavia even over 70%.
As a result of the historical development in the past decades, Czech people have come to have a rather strange relationship with wood.
1. Is the service life of a wooden house shorter than that of a brick one?
Wooden constructions stand for centuries and in terms of durability can be fully compared with constructions built from other materials. It all depends on the purpose for which they are built and on the care that we pay to them during their existence. People tend to forget that they need to diligently care for everything that they expect good service from. As a matter of course, modern wooden houses must meet all the strict legal and standard requirements for strength, stability and durability.
2. Wood is flammable. Does it mean that it will be more probable for a wooden house to burn down?
Wood, as any other material, really burns at a certain temperature. The technical standards, however, state that wooden structures are fire resistant. This sounds like a paradox, but it is not so difficult to understand. The carbonized surface layer which is created on the bearing elements (beams) during a fire precludes further burning (in large pieces of wood, the fire penetrates roughly 2–3 cm deep and further burning is slowed down or stopped, as the surface layer becomes charred and prevents the access of oxygen).
During a fire, ignition of the interior, furniture, textile and appliances is the most dangerous for the inhabitants. It could be argued that wood burns in a predictable way which can be calculated and partly managed. This brings a considerable advantage in fire fighting. All technical standards applied for wooden houses must reflect this situation. Modern wooden constructions are highly fire resistant. Steel structures collapse abruptly, unpredictably and virtually all at once. Parameters of each wooden building must ensure a sufficient evacuation time, which is always in the order of tens of minutes. The fire brigade is well aware of this. In the post 9/11 USA, steel frames of some buildings are protected by wood panelling!
3. Can a wooden house be destroyed by fungi or woodworms?
Yes, it can – if it is designed and built without sufficient experience. It often holds for self-help constructions and when the building is not properly and frequently maintained. Every house, even a brick one, with time becomes dilapidated and turns into a ruin if left without maintenance. The construction of a modern wooden house has to be consulted with professionals. The fundamental prerequisite is quality knowledge and experience of both the architect and building company. The priority is a perfectly mastered design detail and knowledge of the principles of the so-called “structural wood protection”. These prevent the penetration of moisture into the construction, and the construction elements are also protected against the air flow. Structural protection always takes precedence over chemical one. Wood and wooden parts must not be designed to be used in places where they are not able to fulfil the task due to the nature of things – below the ground level, for example. Moreover, technological processes must be strictly followed during the construction.
4. Wooden houses are thought to have worse thermal insulation parametrs than brick houses. Are they colder and difficult to heat up?
The opposite is true! When you put the heating on in a wooden house, the interior is almost immediately warm. In a brick house, on the other hand, the heating has to be on for several hours before you feel warm, because the warmth first accumulates in the walls. Most of our projects (even the standard ones included in the catalogue) offer much better thermal insulation parameters than similar brick buildings. The key to this is the principle of our construction technology – usually a wooden frame filled with contact insulation. Both bearing and thermal insulation elements are thus integrated. It is true that wooden constructions are light and usually accumulate less heat. However, this can be viewed as an advantage – with a wooden house, we heat directly the air inside and the heat is not first stored in the heavy constructions, as is the case with brick buildings. If we decide to accumulate the heat, it is possible to do so in wooden houses too – by inserting a brick or concrete element.
5. Mus a wooden house look like a lodge or cabin?
The design of a modern wood-based house always depends on how the idea of an enlightened customer (builder, constructor, investment company) as to the functioning of the house meets with the creativity of an architect knowing his way round the technology of wooden structures and with the practical experience and skills of the designer. The traditional form of a lodge or wooden cabin is technologically and artistically long outdated.
6. Many people imagine a wooden house as the infamous prefabricated house type "Okál". Are there any better solutions?
In the minds of many builders, the okál houses are deeply stored as a discouraging example of an obsolete wooden house. Development and progress have come to a completely new era and to see a wooden house as an okál is like comparing a Trabant with Škoda Octavia. New materials which were certified after the Velvet Revolution, technologies, heating systems, appearances and solutions have set a completely different direction for wooden houses.
7. Many people imagine a wooden house only as a weekend house or a temporary arrangement. Is it justified?
This is related to the Czech tradition of spending the weekends in weekend cottages. A tradition which we need to disengage from when evaluating wooden houses. It is difficult to persuade people living in a prefabricated block of flats to abandon such a view on using wood. The facts that we have mentioned so far should inspire at least the younger generation to think about what home they would like to live in with their children. Worldwide experience has shown that there is no type of building that would not be possible to construct using the advantages of wood, including large-scale administrative buildings, shopping centres and sports halls.
8. Do you think that using wood for construction of houses damages the environment?
It is strange that people mind a meadow on which a new forest will grow and liven up the landscape more than a quarry which is an eyesore and can be seen from a distance and no new stones will ever grow in it. The production of a clay brick, one kilogram of cement, lime, glass concrete or steel consumes much more energy than producing a single wooden beam. Wooden buildings come from the only Czech fully renewable raw material. At the moment, our overall supply of wood in forests exceeds twice that of the First Republic. Having said that, Czech building industry uses less wood than for example Portugal with hardly any forests. Annual increases of wood in our forests are one fourth higher than their planned exploitation. There can be thus no question about damaging the environment or inappropriate felling of trees. The problem remains our inability to find demand for wood on the domestic market.
9. My house, my castle, people say. But is a wooden castle not more of a shelter for the poor and destitute?
It depends on your perspective. Again, this has a historical tradition, this time in the form of various “shepherd’s huts” and parts of houses for retired people (“vejminky”) where the poor or the elderly really lived. In the Czech society, the investment into a house is still understood as a multigenerational accumulation of family or “ancestral” capital, not as mere consumption of our earthly goods, even though the latter is actually true. But people also measure the utility value of a residential building and the investments into it. I dare say that in the long run a wooden house will bring you more comfort for healthy living with overall lower operating costs. A well-built wooden house will bring considerable energy savings, which should, with the constantly rising prices, be of interest to anyone wanting to build economically.