At the beginning of the XXth century, English settlers brought the method of timber framing to North America. Since then, the method based on utilizing light timber frame has taken roots in American culture. It is said that an Englishman- William Manning was the first who, in the early XIXth century, created the archetype of what later became known as the timber frame construction (Szwedzkie budownictwo 2007). Over the years, the technology was constantly passed on and improved as the next generations wanted to create a design which would be appealing to the majority of future homeowners and, at the same time, relatively cheap ande easy to build. The intense economic boom coupled with the extremelly pragmatic worldview held by American citizens have standardised timber frame house building.

     The application of new finishing materials was also guided by the new standards. As a result, the system is based on a light and durable wood-frame construction filled with insulation and covered with high quality sheathing. In the end, the American “Timber-Frame” house building system was born.

     The economic transformations (which have taken place in Poland in the last years) along with expansion in trade, new technologies and building materials have had an enormous effect on the growing popularity of timber frame house building. Due to a range of creative ideas, the industry has begun producing much smaller wooden elements while, at the same time, keeping extremelly high levels of their durability.

     The idea of laminating timber with glue broadens the ability of applying small dimension wooden components in timber frame house building even further. The origins of engineered wood can be traced as far back as the XIXth century. Glue laminated timber has an ever growing group of proponents due to its durability as well as high quality of the application-specific performance.

     ‘Heban’ applies wooden frames made of glue laminated timber in its process of making prefabricated, energy efficient timber frame houses.

      Based on the standardised requirements, the production process starts with drying and seasoning of the material in question. The goal here is to bring its moisture content down to 10-14%. As soon as drying is over, a quality check takes place where all imperfections are being sawn off. Later on, the material undergoes mortising which allows us to make the so-called ‘finger joints’. After mortising, all elements are glued together and, later, are put through a surface planer in order to achieve a uniform overall thickness of 24mm. Moreover, the elements are then glued again in order to obtain the desired dimensions and mortised. The above mentioned technology allows us to produce wooden pieces which are characterised by countless advantages over solid wood.

     Przeprowadzone kolejne badania pod kierunkiem Prof. dr hab. Gintera Hruzika z Mechanicznej Technologii Drewna przy Uniwersytecie Technologiczno - Przyrodniczym w Poznaniu potwierdzają celowość zastosowań drewna klejonego w budownictwie szkieletowym. Na konferencji naukowo-technicznej, która miała miejsce w Tucholi, 20go kwietnia br. prelegenci  przedstawiali wyniki swoich prac badawczych. Wyniki pokazały, że kluczowe znaczenie podczas produkcji klejonego drewna konstrukcyjnego mają: rodzaj zastosowanego kleju, utrzymanie odpowiednich warunków podczas samego procesu klejenia oraz dobór drewna przeznaczonego do tego procesu.

     This production process has been thoroughly researched under the auspices of Prof. Ginter Hruzik who represents the school of applied sciences at the University of Natural Sciences in Poznań. The findings of the research support the idea that glue laminated timber is ideal for timber frame house building. During a conference which took place on the 20th April 2009 in Tuchola, all researchers highlighted the importance of paying attention to such variables as the type of the glue applied, proper environmental conditions during the production process and the quality of the timber used.

The detailed description of the above mentioned research will be published during the 7th annual conference entitled ‘Wood and Engineered Wood in the Housebuilding Industry’ which is organised by ZUT in Szczecin.

Other crucial properties of glue laminated timber are as follows:

• geometric and dimensional stability- glue laminated timber has an extremely high ability to retain its shape when exposed to prolonged stress
• durability - wood as a natural resource is very durable when exposed to ‘aggressive’ conditions (as opposed to steel and concrete). As a result, it has wide ranging applications in environments of extreme moisture or high salt content (e.g. coastal towns and villages)
• fire resistance - glue laminated timber (when planed correctly) is very fire resistant. In case of heavy fire, the exterior of the wooden construction gets charred, thus, protecting the interior which, in turn, is extremely important when it comes to the preservation of load bearing properties of the building
• energy efficiency - wood, as a building material, can be applied in a range of climates both hot and cold. This is possible to its natural ability to block heat rather than radiate it
• natural beauty as well as other aesthetic factors - wood, as one of natural resources known to man, has a broad range of colours, structures and textures available. As a result, the inhabitants of wooden structures usually highlight the aesthetic properties of wood as creating not only comfortable but also relaxing living conditions. In some cultures, the application of glue laminated timber is a sign of prestige
• affordable costs - the application of glue laminated lumber in house building leads to lower production as well as transportation costs. Lighter timber frame creates a smaller load for the load bearing components. Moreover, thinner walls lead to a much greater total living area (around 10%)
• eco-friendliness - as opposed to steel frames, glue laminated timber does not require constant maintenance or renovation. Furthermore, the glues used in the production of glue laminated timber are not toxic

      These (along with a range of other factors) have made glue laminated timber the most widely applied building material. It is commonly used in the most daring projects (i.e. sports halls). However, due to its wide ranging properties, it has gained popularity in timber frame house building.

Grzegorz Gołuński
Tuchola, June 2009   

The above article was slightly changed and published in ‘Gazeta Przemysłu Drzewnego’ which is a leading publication in our industry