| Other names: | Belgian, German, French, native, Polish, Romanian, Slavonian, Spessart oak, depending on origin (Netherlands), chêne (France), Eiche (Germany), oak (Britain). |
| Botanical name: | Quercus petraea (Mattuschka) Lieblein (= Q. sessiliflora Salisb.), Quercus robur L. (= Q. pedunculata Ehrh.). |
| Family: | Fagaceae. |
| Growth area: | Europe and Asia Minor. |
| Tree description: | Height 18-30 m, maximum 45 m. The straight branch-free trunk is up to 15 m long and has a diameter of 1.2-1.8 m. The oak tree can reach a high age (400 years). |
| Supply: | Sawn timber, unedged timber, edged timber and veneers and finished products. |
| Wood description: | Oak wood properties: Oak heartwood has a yellow-brown to dark brown colour and stands out clearly against the 25-50 mm wide pale brown sapwood. Texture and quality vary depending on growing conditions. For example, Slavonian oak is slow and evenly grown, has a straight grain and an even hue, and it is soft and easy to work. Oak from Poland is tougher and harder. Domestic oak tends to be harder, heavier and firmer, stronger but also coarser than imported oak. Oak has a high tannin content, so metals in contact with oak corrode quickly. |
| Wood type: | hardwood |
| Thread: | Right. |
| Nerf: | Moderately coarse to coarse. |
| Volumetric mass: | (500-)670- 710-760(-970) kg/m3 at 12% moisture content, fresh 900-1200 kg/ m3. |
| Works: | Medium (VM ± 640 kg/m3. Large (VM ± 725 kg/m3. |
| Drying: | Very slow. Some tendency to cracking, deformation, and discolouration are present in this process, especially in the initial drying periods. It is recommended to apply a sealant to head wood to avoid head cracks. Oak, however, dries very well with the necessary precautions. |
| Workability: | Its machinability is highly dependent on its volumetric mass. However, oak is generally easy to machine, turn and mill, both by machine and by hand. Oak, once dried to the required degree of dryness, works moderately. |
| Nailing and screwing: | Moderate. Pre-drilling is recommended. Stainless fixing material is recommended, otherwise blue-black discolouration occurs in contact with iron and light brown discolouration in contact with copper or brass. |
| Adhesives: | Good. |
| Bend: | Very good. |
| Surface finish: | Good. Oak lends itself well to stain treatment, smoking, leaching, etc. When using (clear) water-based finishers, the high tannic acid content should be taken into account. |
| Sustainability: | Fungi 2. Anobium G. Termites M. Spider mites are susceptible to infestation by Lyctus. |
| Strength class: | Polish oak was classified in strength class K24 in a limited test in 2000, according to NEN 5498:1997. |
| Impregnability: | Heartwood 4. Sapwood 1. |
| Particulars: | Wet wood is corrosive in contact with iron. Blue-black discolouration results from the reaction between iron and the tannic acid (tannin) in the wood. Oak in contact with cement or concrete will delay its hardening. American oak grown in the Netherlands, marketed as native American oak, comes from Quercus rubra Du Roy |
| Applications: | The wood can be used in almost every industry and almost everywhere, both for construction timber, in shipyards, for bridge building and waterworks, and in the chemical, furniture, toy, sports articles, bodywork and agricultural machinery industries. Also for window frames, windows, doors, parquet and strip flooring, plywood and veneer, fenders, bridge decks, chutes, railings, wagon and ship floors, church furniture and tools. The native oak is specially used for construction timber (restoring old buildings) window frames, windows, beams, commercial floors, ladder rungs (ash is better), ship keels and skins, sleepers, fenders, bridge decks, piles, lock gates, dolphins, embankments, etc. European oak is irreplaceable for making barrels for wine, sherry, cognac and other alcoholic beverages that derive much of their flavour from the tannins present in oak. |
| Quality requirements: | European oak is listed in Dutch code of practice NPR5493:1999, Quality guidelines for hardwoods in hydraulic engineering works. Two Dutch standards for European oak appeared in 1983 in the series Quality Requirements for Timber (KVH 1980), NEN 5476 Wood type European oak. Unedged and NEN 5477 Type of European Oak. Squared. European oak complies with the requirements mentioned in the assessment guideline (BRL) 2908/01 Wood dowels. |
source: houtvademecum 10th revised edition centrum hout almere
