What is the heavy prefabricated wooden technology and what is the difference between it and the so-called Canadian technology, popularly known on our market? What do the two technologies have in common and what separates them? Is it only that both are based on a structure made of wood? We will try to answer these and many other questions throughout our blog series, all in order to bring as much as possible the elements related to making an important decision related to the selection of the right construction technology.
As frame technologies for building houses are still technologies that are just developing on the Polish market, and although investors’ awareness of this topic is still growing, we often come across erroneous opinions on our way. In the general consciousness of investors, there are often mantra phrases that are used without much thought, such as “passive house” or the colloquially common name “Canadian”, which, however, cannot be identified with all frame buildings. Prefabricated or Canadian – today this list reigns on our blog!
Today we would like to present these similarities and differences between two technologies: heavy wooden prefabricated (German technology) and the Canadian light system (as the name suggests, originating from overseas, specifically from Canada).
– Heavy construction/stable
– thick wall cross-sections (large number of insulators)
– high sound insulation
– Scandinavian technology (severe weather conditions)
– closed prefabrication system (appropriate conditions)
– precision of production – a specially adapted factory
– THERMAL INSULATION – ensures energy savings (energy efficiency)
– short lead time
– possibility of using concrete screeds
-Prefab. Sheathed with construction plates on both sides
– no restrictions on architecture (very complex projects)
– freedom in the use of finishing materials (regardless of weight)
-no restrictions on roofing
– freedom in interior design
– large wood cross-sections (certified only)
– Fermacell constr board
– 60 x 160 80x 240 – KVH solid structural timber
– glued laminated timber with a moisture content of 12% – 18%
– thinner, lightweight design
– much smaller cross-sections
– On-site production in open conditions
– open prefabrication system exposed to inconvenient conditions
– No need for heavy equipment
– poor acoustic qualities
– no possibility of using concrete screeds
– thin walls prevent the installation of heavy finishing elements
– possibility of using only light roofing
– reputation for a perishable, cheap alternative
– plasterboard walls
– technology from the United States
– structural sheathing only on the outside
Both heavy precast and Canadian technology are based on a wooden frame. Their production is based on the use of structural timber and a number of insulators in order to obtain the best thermal insulation properties. Both technologies can also be classified as ENERGY-EFFICIENT, where low building maintenance costs are an undeniably huge advantage. Made of appropriate quality wood and other materials, they guarantee fire resistance and do not require impregnation with harmful chemicals, and the relatively low weight of the structure makes them ideal solutions for areas located on mining damage. Also, the short implementation time, lack of seasonality and the possibility of immediate residence in the completed building are identical to both technologies, not to mention the durability and longevity of properly executed projects.
However, we can distinguish much more differences than similarities between the two technologies. Despite the use of similar types of materials, one of the fundamental differences that we can highlight are significant differences in the cross-sections of walls and structures. In the Canadian system, the structure of walls, floors and roofs is supported by elements 38 mm (1 1/2 inch) thick. Hence, this system is often referred to as a lightweight frame structure. The structure is stiffened by wood-based panels mounted on the outside of the external walls. The construction of a house in the German system is a heavy structure in relation to the Canadian system. In the German system, the structure of walls, ceilings and roofs is based on elements 60 mm thick. Solid wood elements with a width of 160 mm are used for the wall structure, with higher loads these values increase depending on the needs. The wall is filled with insulating material and the stiffening of the prefabricated element is a double-sided covering of them with a fermacell construction board with increased resistance.
The increased strength/load-bearing capacity of the structure in the prefabricated technology also affects the possibility of using concrete screeds on ceilings, where in the case of a lightweight Canadian structure this procedure is not used. Also the roofing and finishing elements used in heavy wooden prefabricated elements, due to the high load-bearing capacity of the structure, leave freedom and freedom of the materials used, while in a typical lightweight structure it determines compliance with the
The above differences also translate into the way they are fabricated and assembled in both technologies. Canadian frame buildings are manufactured and assembled directly on the construction site, and due to their lightness, they do not require the use of heavy equipment for assembly. On the other hand, buildings constructed in heavy prefabricated wooden elements are manufactured in closed conditions of a specially adapted production hall, from where they are transported to the construction site, where the elements are assembled by a crane. The so-called closed prefabrication of buildings allows to ensure appropriate production conditions and requires extreme precision of workmanship (there is no room for errors during assembly on the construction site). The closed prefabrication system allows you to plan the production process, which often requires thorough preparation in the case of very complex and extensive projects.
As it is not difficult to see, comparing the above similarities and differences, both technologies, although often identified and identified, are characterized by both a different genesis and a different nature of the design. Prefabricated or Canadian house? Ultimately, the decision depends on the individual needs, views and expectations of the client.