Northern pine - ideal raw material for log housing

The quality of log depends on the raw material and processing. We use only the best materials and northern pine close to the Arctic Circle is the finest material for a log house due to ideal soil conditions and a short period of growth in the north.

Northern pine has extremely tight growth rings (i.e. annual rings), which makes it most durable and the strongest construction material. The same quality cannot be found outside arctic forests.

Log types for every need

When choosing a log type, you start by thinking of the looks and the use of the house. Our selection is there to meet the requirements of our customers in their various projects.

Further information on laminated (glued) logs

Further information on round logs

Further information on rectangular logs

Further information on the wall structures with additional insulation

The best log profile for air tightness

A tight log house is energy-efficient. Kontio structures with all the details have been carefully designed to fulfill high demands of the building regulations of residential houses today. A tongue-and-groove type recess, which has been cut in the shape of the log, ensures a tight construction with minimal settling, thanks to dimensional accuracy and recess width.

A separate space has been cut in the log structure for insulation, keeping it protected from storms and rains. King-size laminated logs make stately wood architecture, and there is no need for extra wall insulation, even in Arctic conditions.

Log house suits all climate conditions

Log houses have taken place in all different climate conditions around the World. Kontio Log House is known to withstand not only extreme weather conditions, but earthquakes, massive snowloads and typhoons. Kontio has been certified to fullfil the requirements of CE sign for it's log houses. This certificate can be found only from very few producers which are able to follow the highest requirements. The quality certificate proves that the log buildings manufactured by Kontiotuote Oy meet the requirements set forth by EU countries in ETA decision ETA-05/0119.

A Kontio Log House bears seismic loads well

In order to bear seismic loads, a building must endure both horizontal and vertical transitions without collapsing. Rigid and brittle structures as a rule do not function well in earthquake situations, since even small transitions could induce serious breaks.

Kontio Log House has a dense structure with elastic joints. The structure has strong capacity for deformations and therefore endures them well. The lightness of wooden structures and the clear design also help in enduring the strain of an earthquake.

Seismic loads, both horizontal and vertical, are taken into consideration when planning the structural details of a Kontio Log House. The structures for each building are planned individually and taking into consideration the local values for seismic loads (Eurocode). The house and its joints endure the required amount of seismic loads, and sufficient anchoring will be able to carry these loads to the foundations.

Tight log house is energy-efficient

The tightness has been verified in tests conducted by VTT Technical Research Centre of Finland. As a result of product development efforts, good design and meticulous construction, a building with 205 mm laminated log walls erected in Oulu in 2005 reached the tightness value of N50 = 1.5 1itres/h. It is an excellent result! The test conducted by the Technical Universities of Tampere and Espoo showed that the average tightness value of 100 timber frame houses was 3.9 l/h. 4 l/h can be regarded as a good tightness value. A "traditional" log house where wool insulation is used in joints and neck joints reaches the same level, i.e. 4.

The total heat demand in a building with a 1.5 l/h tightness level is by circa 10 percent lower than that in a 4 l/h building. If the tightness of a log house with 205 mm laminated logs is improved from 4 to 1.5, the total heat demand in the building is the same as in a building with 300 mm laminated logs and the tightness of 4 l/h.

The good fire resistance of log

In bodily injuries caused by a house fire, the material of the frame of the building is rarely the decisive factor. Even a stone house has a fire load, with easily burning materials in interior walls, floors, roof slabs and especially in furnishing. The furnishing is often the critical factor as far as bodily injuries are concerned because it has the greatest impact on the speed of fire spread at the initial stage. Flammable furniture, textiles and other articles produce the most dangerous element of a fire: toxic fume.

Good fire resistance features of log comes from the nature of the wood material: the burnt surface of the wood efficiently prevents a fire from spreading. Massive wooden structure maintains its bearing capacity for long and does not collapse suddenly, thus giving people time to save themselves. (Technical Research Centre of Finland by request of Finnish Log House Association HTT ry.) The classification system of the fire resistance of structural parts is based on testing methods and rules in accordance with EC standards.

Protecting the log surface

A mild water-soluble wood protective liquid is sprayed onto log surface at the factory. It provides protection against possible weathering and moulding for the period of transportation and the starting phase of construction operations. Log surfaces in the open air must, however, be protected with wood protective liquids before surface treatment.

Painting gives the building an individual look that is suitable for the surroundings. Moreover, surface treatment protects wood against moisture and the sun's ultra-violet radiation and prevents the growth of mould and rot fungi. Indoors in dry rooms, surface treatment is not necessary. In this case, the sun's UV light will make the surface darker in the long run.