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European Oak has an elegant look which is full of character and with more grain change and colour variation than American oak. The colour of the oak can range from light tan to deep brown shades and will deepen to a more medium “honey” over time. There will be wild grain, pin knots and burrs in this oak flooring which are attractive and add more character to the boards.
This is an acceptable appearance in the timber. The European oak flooring has many characteristics which can blend well with modern and historic interiors. It is sourced from all over Europe.
The European oak flooring is available in an unfinished oak floor, oiled floor or lacquered finish. The lacquered is the most common finish which gives a full protective coating over the flooring. The oiled finish gives a more natural look and feel as the oil is absorbed into the wood and protects it with natural oils.

White oak is the general classification for a majority of the oak species. The oak timber from the Southern states of America comes from a large number of species which have a wide variation in the colour, grainage, density and character markings. The Northern states has less species therefore there is a more consistent and uniform colour and appearance.
In general, the characteristics including the grain are similar to the European oak but there are less knots and a slightly warmer colour. As with the European oak the colour of the oak can range from light tan to deep brown shades but does not deepen to a medium “honey” over time. The hardness of White oak is 108% on the Janka scale.

The White oak flooring is available in an unfinished oak floor, oiled floor or lacquered finish. The lacquered is the most common finish which gives a full protective coating over the flooring. The oiled finish gives a more natural look and feel as the oil is absorbed into the wood and protects it with natural oils.

The American Red Oak has much warmer and slightly “pink” tones, which has a medium range of colour variability which can range from light tan colours with pink highlights to dark browns.
There are two distinctions of red oak – the northern grown timber which is found along the Canadian border tends to be lighter and more uniform in colour than the Southern grown timber, which has a coarser grained texture with more dark mineral staining and black knots. Over time there is a medium amount of colour change with a slight “honey” tone replacing the pinkish brown colour.
The hardness of the red oak is 1260 on the Janka scale.

Knots
Knots A knot is a particular type of imperfection in a piece of timber, which reduces its strength, but which may be exploited for artistic effect. In a longitudinally-sawn plank, a knot will appear as a roughly circular "solid" (usually darker) piece of wood around which the roughly parallel fibres (grain) of the rest of the "flows" (parts and rejoins).
A knot is actually a portion of a side branch (or a dormant bud) included in the wood of the stem or larger branch. The included portion is irregularly conical in shape (hence the roughly circular cross-section) with the tip at the point in stem diameter at which the plant's cambium was located when the branch formed as a bud. Within a knot, the fibre direction (grain) is up to 90 degrees different from the fibres of the stem, thus producing local cross grain.
During the development of a tree, the lower limbs often die, but may persist for a time, sometimes years. Subsequent layers of growth of the attaching stem are no longer intimately joined with the dead limb, but are grown around it. Hence, dead branches produce knots which are not attached, and likely to drop out after the tree has been sawn into boards.
In grading lumber and structural timber, knots are classified according to their form, size, soundness, and the firmness with which they are held in place. This firmness is affected by, among other factors, the length of time for which the branch was dead while the attaching stem continued to grow.
Knots materially affect cracking (known in the industry as checking) and warping, ease in working, and cleavability of timber.
They are defects which weaken timber and lower its value for structural purposes where strength is an important consideration. The weakening effect is much more serious when timber is subjected to forces perpendicular to the grain and/or tension than where under load along the grain and/or compression. The extent to which knots affect the strength of a beam depends upon their position, size, number, direction of fibre, and condition. A knot on the upper side is compressed, while one on the lower side is subjected to tension.
The knot, especially (as is often the case) if there is a season check in it, offers little resistance to this tensile stress. Small knots, however, may be so located in a beam along the neutral plane as actually to increase the strength by tending to prevent longitudinal shearing. Knots in a board or plank are least injurious when they extend through it at right angles to its broadest surface. Knots which occur near the ends of a beam do not weaken it. Sound knots which occur in the central portion one-fourth the height of the beam from either edge are not serious defects.
Knots do not necessarily influence the stiffness of structural timber. Only defects of the most serious character affect the elastic limit of beams. Stiffness and elastic strength are more dependent upon the quality of the wood fibre than upon defects in the beam. The effect of knots is to reduce the difference between the fibre stress at elastic limit and the modulus of rupture of beams. The breaking strength is very susceptible to defects.
Sound knots do not weaken wood when subject to compression parallel to the grain. For purposes for which appearance is more important than strength, such as wall panelling, knots are considered a benefit, as they add visual texture to the wood, giving it a more interesting appearance.

Heartwood is wood that, as a result of genetically programmed processes, has died and become resistant to decay. It appears in a cross-section as a discolored circle, following annual rings in shape. Heartwood is usually much darker than still living wood, and forms with age. Many woody plants do not form heartwood, but other processes, such as decay, can discolor wood in similar ways, leading to confusion. Some uncertainty still exists as to whether heartwood is truly dead, as it can still chemically react to decay organisms, but only once (Shigo 1986, 54).
Sapwood is living wood in the growing tree. All wood in a tree is first formed as sapwood. Its principal functions are to conduct water from the roots to the leaves and to store up and give back according to the season the food prepared in the leaves. The more leaves a tree bears and the more vigorous its growth, the larger the volume of sapwood required. Hence trees making rapid growth in the open have thicker sapwood for their size than trees of the same species growing in dense forests.
Sometimes trees grown in the open may become of considerable size, 30 cm or more in diameter, before any heartwood begins to form, for example, in second-growth hickory, or open-grown pines.
As a tree increases in age and diameter an inner portion of the sapwood becomes inactive and finally ceases to function, as the cells die. This inert or dead portion is called heartwood. Its name derives solely from its position and not from any vital importance to the tree.
This is shown by the fact that a tree can thrive with its heart completely decayed. Some species begin to form heartwood very early in life, so having only a thin layer of live sapwood, while in others the change comes slowly. Thin sapwood is characteristic of such trees as chestnut, black locust, mulberry, osage-orange, and sassafras, while in maple, ash, hickory, hackberry, beech, and pine, thick sapwood is the rule.
There is no definite relation between the annual rings of growth and the amount of sapwood.
Within the same species the cross-sectional area of the sapwood is very roughly proportional to the size of the crown of the tree. If the rings are narrow, more of them are required than where they are wide. As the tree gets larger, the sapwood must necessarily become thinner or increase materially in volume. Sapwood is thicker in the upper portion of the trunk of a tree than near the base, because the age and the diameter of the upper sections are less.

When a tree is very young it is covered with limbs almost, if not entirely, to the ground, but as it grows older some or all of them will eventually die and are either broken off or fall off.
Subsequent growth of wood may completely conceal the stubs which will however remain as knots. No matter how smooth and clear a log is on the outside, it is more or less knotty near the middle.
Consequently the sapwood of an old tree, and particularly of a forest-grown tree, will be freer from knots than the heartwood. Since in most uses of wood, knots are defects that weaken the timber and interfere with its ease of working and other properties, it follows that sapwood, because of its position in the tree, may have certain advantages over heartwood.
It is remarkable that the inner heartwood of old trees remains as sound as it usually does, since in many cases it is hundreds of years, and in a few instances thousands of years, old. Every broken limb or root, or deep wound from fire, insects, or falling timber, may afford an entrance for decay, which, once started, may penetrate to all parts of the trunk.
The larvae of many insects bore into the trees and their tunnels remain indefinitely as sources of weakness. Whatever advantages, however, that sapwood may have in this connection are due solely to its relative age and position.
If a tree grows all its life in the open and the conditions of soil and site remain unchanged, it will make its most rapid growth in youth, and gradually decline. The annual rings of growth are for many years quite wide, but later they become narrower and narrower.
Since each succeeding ring is laid down on the outside of the wood previously formed, it follows that unless a tree materially increases its production of wood from year to year, the rings must necessarily become thinner as the trunk gets wider. As a tree reaches maturity its crown becomes more open and the annual wood production is lessened, thereby reducing still more the width of the growth rings.
In the case of forest-grown trees so much depends upon the competition of the trees in their struggle for light and nourishment that periods of rapid and slow growth may alternate. Some trees, such as southern oaks, maintain the same width of ring for hundreds of years. Upon the whole, however, as a tree gets larger in diameter the width of the growth rings decreases.
There may be decided differences in the grain of heartwood and sapwood cut from a large tree, particularly one that is mature. In some trees, the wood laid on late in the life of a tree is softer, lighter, weaker, and more even-textured than that produced earlier, but in other species, the reverse applies.
In a large log the sapwood, because of the time in the life of the tree when it was grown, may be inferior in hardness, strength, and toughness to equally sound heartwood from the same log.

Engineered wood products are used in a variety of ways, often similarly to solid wood.
Engineered wood floors are preferred over solid wood in many applications due to a certain comparative advantages:
• Because engineered wood is man-made, it can be designed to meet application-specific performance requirements.
• Large panels of engineered wood may be constructed from small trees.
• Small pieces of wood and wood that has defects can be used in many engineered wood products, especially particle and fiber-based boards.
• Engineered wood products are often stronger and less prone to humidity-induced warping than equivalent solid woods, although most particle and fiber-based boards readily soak up water unless they are treated with sealant or at least paint.

Engineered wood products are more expensive to produce than solid lumber in terms of time, money, and energy, but enjoy economic advantages when manufactured in large sizes due to the rarity of trees suitable for cutting large solid-wood panels.
Although engineered wood products use the resource of wood efficiently and therefore promote natural resource conservation, the required adhesives may be toxic. A concern with some resins is the release of formaldehyde in the finished product, often seen with urea-formaldehyde bonded products.

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