Specification points

About Canadian larch

Canadian larch (botanical name Larix occidentalis) is the largest of the larch species. It grows in the south of Canada in British Columbia, along the eastern slopes of the North Cascades further in the USA in Washington and Oregon. The wood of the Canadian larch is strong and hard, and its lumber is used for a wide range of construction carpentry products such as: floors, railway sleepers, shipbuilding and, due to its durability and resistance to external influences, also for facades, terraces, house structures. Canadian larch trees reach a height of up to 60 meters with a trunk diameter of up to 2 meters. It grows in a relatively humid and cool climate zone, thanks to which there is a small growth of annual rings and a higher density of wood with resin content, thanks to which the wood shows resistance to wood decay fungi. Canadian larch is also known by the names American or Alaskan larch, the natives called it Tamarack or Hackmatack, which in their language means snow-resistant wood, and they often used it for making snowshoes. Canadian larch extracts and its tannins were used for medicinal purposes.

Long life

Due to its slow growth in cold conditions, Canadian larch achieves a high density of around 600 kg/m3 and a natural resistance with a relatively long lifespan of decades. Thanks to its natural resistance to decay, the high content of resins that act as a natural antiseptic that repels wood-destroying insects, and extracts that protect against rot and fungi, it is one of the most durable soft woods. The lifespan of weathered wood depends on many factors and varies by application and project. As with all other types of wood, the durability of Canadian larch is affected by whether it is a walkable horizontal surface or vertical use, such as facade cladding, fences. An important factor affecting the life of wood is proper assembly, application of protective coatings, regular maintenance, roof overhangs protecting wood from UV radiation, rain, the possibility of drying and ventilation of wood and other aspects.

Color and weathering

Wood is a natural material with a natural range of color tones. Color differences are characteristic of the wood and are allowed. Due to UV radiation, climate and humidity, the wood weathers and changes its original color. With a dry environment there is a change to a gray shade, and due to the action of moisture or fallout dirt, there will be blackening and a change of color to a dark shade. The time and degree of weathering depends on the treatment method, location, local conditions, roofing, exposure of the wood to the weather and other influences acting on the wood.

Properties

Canadian larch is one of the heaviest soft woods showing medium stability with a density of around 600 kg/m3. As with all types of larch, Canadian larch is characterized by the appearance of longitudinal cracks in the wood and cracks at the ends, depending on the outdoor climatic conditions. This is a natural feature of this wood species. Furthermore, with Canadian larch, as with all trees, we can encounter peeling of the upper annual rings. Avoid contact of the wood with corrosive metal or metal dust, which creates blue-black stains on the wood. Always use only stainless steel fasteners. If the wood is exposed to the weather, the color and weathering of the surface will occur over time, as is the case with all wood. If you want to restore the original color of the wood, use Saicos degreaser according to the technical sheet. After that, it is recommended to treat the surface with a suitable protective coating. Cana larch shows a high degree of volume changes in the wood, a high degree of twisting, a high susceptibility to cracking, a medium degree of curvature, small growth defects, the occurrence of pith runs, the occurrence of pits and pitch resin, the number of knots is not limited. In order to achieve the strongest attachment, it is recommended to mount the attachment with screws from above to the underlying prisms according to the recommendation on the installation of terraces. Pre-drilling holes for screws is recommended. Mounting on clips is not suitable due to the higher volume drying and degree of twisting of Siberian larch. Wood that is exposed to outdoor climatic influences changes its volume, dries up or grows according to climate changes. There may be slight differences in the width of the battens due to the different expansion of the wood during moisture equalization between the radial and tangential growth of the wood. In wood that is exposed to outdoor climatic influences, there may be cracks, transverse deflection, twisting, twisting, cracks especially at the ends of the boards due to drying, which change depending on the relative humidity of the air or changes in climatic conditions, small holes from wood-destroying insects. The above characteristic properties of wood cannot be considered a defect.

Knots and other natural signs of wood

Knots and eyes, healthy or partially fused, cracks around knots, pith runs, resin canals, marbling and other natural features are an integral part of wood.

High resin content

Resins are natural substances that trees naturally produce to protect themselves from pathogens and insects when damaged. The natural resistance of Canadian larch is due to the high content of resin and preservatives contained in the wood. Canadian larch is very resistant to decay because of its high tannin content. The high content of resins contained in wood can under certain conditions, for example due to higher temperature, flow onto the surface of the wood, especially in the summer months. Even after treating the wood with surface treatment, the resin can migrate to its surface and further through the coating. This is a natural phenomenon for this tree species.

Protective coatings

Terraces made of Canadian larch are recommended to be treated with a suitable water-repellent coating. You will achieve the best results with natural oils Saicos special oil. With Saicos oils, it is possible to choose from both colorless and colored shades with increased UV protection. Canadian larch is very resistant to decay because it contains a high content of tannin. These resins and preservatives act as a natural antiseptic that is very repellent to insects. These larch resins and extracts are credited for creating a high resistance to rot and decay. The primary extractive substance in Siberian larch is Arabinoglactan, which is toxic to wood decay fungi.

Storage

When storing the wood before and during assembly, make sure that the wood is not exposed to direct sunlight, rain, snow and other external influences. It was well covered or best stored in covered unheated areas, with relative humidity values ​​equal to outdoor humidity. At the same time, sufficient spacing of the wood was ensured, allowing for air ventilation and preventing the formation of mold. If these recommendations are not followed, twisting, deformation or other changes in the wood may occur during storage.

Care

Clean the terrace regularly from applied dirt, soil, deposits and pollen. This will prevent macropore dirt from penetrating into the wood. Under objects such as umbrella stands, flower pots, bowls, mats, under which water and moisture settle, there is no possibility of quick and natural drying of the wood. Stains can form under these items from long-term moisture and dirt. Therefore, move these items standing on the terrace from time to time or ensure that there is natural drying and air ventilation under them. This will prevent the formation of dark spots on the wood. You can find more information about the care of wooden terraces here.