LVL Ultralam™
From the ancient times, the tree was one of the most demanded and widely used construction materials. However, despite all its advantages, the wood has an entire range of significant drawbacks such as susceptibility to rotting, combustibility, geometrical instability under humidity variations, loss of strength due to knots and wood defects, insufficient density, limitations of linear dimensions, deformation in humid environments, checking, shrinkage etc.
All these drawbacks have always limited the scope of timber application in construction. But today, thanks to the new technologies, the wood is really getting a new lease on life. New hi-tech methods of wood processing have absolutely altered the properties of this material and enabled to create wood based products that multiply all the advantages of the wood and reduce all its drawbacks almost to zero.
These materials boast fundamentally new features allowing to use wood products in the applications one could only dream of before. It is these hi-tech developments that gave birth to laminated veneer lumber, a product of wood working industry manufactured as billets, boards and beams.
LVL (laminated veneer lumber) is a technologically enhanced and improved high strength structural wood based material. The complex technological process results in a homogenous material with unique performance. LVL properties significantly exceed those of solid wood, glulam and high-grade timber.
The main raw material used to produce LVL is wood veneer of various grades (wood species and mixtures thereof differ from manufacturer to manufacturer). Term “LVL” was introduced in 1960s by Wayerhauser (US company) who had developed this product and launched the first LVL production line ever. Now LVL is rightfully considered to be the best wood material in terms of technology, reliability and performance.
Its outstanding properties place LVL among the most advanced and technological products currently used in construction.
LVL enjoys unique strength characteristics, for example, its MOE (modulus of elasticity) is 24% higher than that of solid spruce, while its MOR (bending strength) is twice as high. These physical characteristics ensure high bearing capacity of LVL products at smaller cross-sections which in its turn significantly reduces the total volume of required lumber.
These high characteristics are associated with a number of specific features of LVL production process that ensure the absence of natural wood defects in the structure of the material.
Due to its laminated structure and production technology, LVL is an entirely homogenous material with unchangeable mechanical properties lengthwise and consistent performance irrespective of seasonal factors. That is, it’s a material with homogenous symmetrical structure that does not change its performance over its entire service life.
Apart from conventional timber materials, LVL products are capable of maintaining precise linear dimensions in spite of seasonal factors, variations in environmental and climatic conditions. LVL neither warps nor buckles when exposed to humidity, neither checks nor rots, offers minimum natural shrinkage and absorbs practically no moisture. Therefore, the dead weight of an LVL beam remains unchanged in humid environment.
The stability of LVL linear dimensions ensures high accuracy of adjusting parts which underlies durability and long lasting appeal of LVL structures as opposed to solid wood products susceptible to swelling and buckling. Apart from metal and reinforced concrete, LVL offers higher resistance to corrosive agents, such as water vapors, ammonium, salty vapors etc. That is why it’s indispensable in the construction of aquatic parks, swimming pools, agricultural and industrial structures.
LVL boasts better fire resistance compared to ordinary beams. This is achieved through multiple layers of veneer and less porosity of material. Phenol-formaldehyde resin is neutral to oxidation and doesn’t support ignition. High density and absence of cracks prevent from fire propagation and thermal effects inside the material. LVL test results demonstrate the ability of the material to maintain its properties within 30-60 minutes at 300°C. Under the specified temperature the beam undergoes slow charring at the rate of 0.6 mm/min flatwise and 1 mm/min edgewise.
LVL significantly improves and accelerates construction techniques making it possible to avoid welding and to use lighter lifting machinery at the construction site.
The price of LVL is a little bit higher than average prices for other timber materials. However, LVL-based products maintain their geometry even in as much as ten years which, certainly, justifies the manufacturer’s costs. As opposed to such ordinary construction materials as metal and reinforced concrete, LVL boasts an optimal performance/weight ratio.
This factor is of special importance for low-rise construction, as with an adequate strength reserve, LVL-based structures do not require reinforced foundations and are easy to install, i.e. they can be moved on the ground and lifted onto upper stories without special machinery. As a result, LVL based buildings require much less money and time, as opposed to brick and concrete structures.
LVL structural and installation properties have ensured its widespread use in North America and Western Europe. The world wide proven technology of LVL-based prefabricated homes building enables to build energy efficient houses of any architectural shapes and sizes within the shortest time frames. And be it a modest country cottage or a large luxury mansion, they will have one thing in common: reliability, quality and comfort provided by the material specifically created for these purposes, the “superwood” LVL.