A Guide to Timber Technologies

Transcription

1 A Guide to Timber Technologies Timber Technologies

2 Osmose Introduction Osmose, an international timber technology company, has been and continues to be, a catalyst for change and innovation in the European timber treatment industry. Most people associate Osmose with timber preservation but that is only part of the picture. Osmose is a provider of a wide range of timber technologies that create new commercial opportunities for timber. Whether it is through the use of formulations using proprietary technology or through the application of software, developed in-house, to optimise the production process, Osmose is dedicated to expanding the usage of sustainable managed timber products in a way which provides real benefits for their trading partners. Osmose research and development centres positioned around the world share technology and knowledge that helps create world class products. Osmose is the leading name in the industry with ISO 9001 and ISO accreditations. Wood Wood is a beautiful building material; it is attractive, natural and extremely versatile. The modern home and garden can be transformed with the multitude of timber products available today. Wood can be a source of food for decay fungi and certain species of insects so it needs protecting with modern preservative systems. Modern technologies when applied to timber can enhance it and make it even more adaptable and attractive. These innovative timber products are Creating New Opportunities for Timber. Osmose Engineering The timber industry recognises that Osmose is well positioned to successfully commercialise the next generation of timber enhancement technologies. Effective and modern application plant design is a vital part of the necessary system support package. Timber treaters are placing an ever stronger emphasis on software. This demand for more efficient computer controlled processing plants is particularly important with the new timber technologies. Osmose s engineering design team develop plant and software solutions that help create new opportunities for timber. The TIMBER TREATER function of the Osmose WorkNet helps companies to treat timber efficiently and effectively. Process Control System

3 The Importance of Timber Preservation Timber Technologies

4 Enemies of Timber Termites Commonly but erroneously called white ants termites are the most destructive of woodboring insects. They do not occur in the United Kingdom, but are widespread throughout the Tropics, the United States, Australasia and to a lesser extent Continental Europe. In addition to timber some species also attack standing trees, food crops and many other materials including plastics and rubber. Broadly speaking, they fall into two main groups: Dry Wood Termites (Kalotermitidae) These work entirely within the wood and often remain undetected until serious damage occurs. Attack is initiated by the flying adults laying their eggs in cracks or joints in woodwork, furniture, etc. These insects are mainly confined to coastal regions. Subterranean Termites These are more widely distributed and live in colonies in the ground. They construct mud tunnels which protect the workers foraging for food from predators and desiccation. These mud tunnels are a sure indication of termite infestation. The three most common groups of subterranean termites are the dampwood termites (Termopsidae), moist wood termites (Rhinotermitidae), and ground dwelling termites (Termitidae). Pore Fungus (Fibroporia vaillantii) This is another of the wet-rot fungi which feed on damp softwood, causing its ultimate collapse. It tolerates more extreme temperature conditions than the dry rot fungus. Its mycelium is usually formed in fan-shaped formations over the surface of the timber and is snow-white in colour. Its fructifications and spores are likewise light in colour. It is a common fungus in coal mines but is also found in damp buildings. Dry Rot (Serpula (Merulius) lacrymans) This fungus requires moist, warm, windstill conditions for its growth and untreated timber at a moisture content above 22%. The cellulose which it attacks is broken down to carbon dioxide and water, causing the timber to lose strength, to develop cuboidal splitting and become dry and powdery hence the name dry rot. The strands or hyphae of the fungus produce enzymes which digest adjacent damp timber. Strands may penetrate through brickwork, following the line of damp, in search of further timber to attack. Under ideal growing conditions the fungus can fructify within a year producing a fleshy fruit body from which millions of rust red spores are discharged. Fungi Cellar Fungus (Coniophora puteana) Cellar Fungus is one of the wet-rot fungi, which feed on damp timber, causing the wood to lose weight and strength and ultimately to collapse. Wet rot fungi require more moisture than the dry rot fungus. Unlike Serpula lacrymans this fungus does not form a fleshy fruit body but a thin, olive green, flat sporophore. Characteristic dark brown strands develop on the timber surface. It is often found in cellars or wherever persistent dampness is present.

5 Enemies of Timber Wood-boring Insects Common Furniture Beetle (Anobium punctatum) This wood-boring insect can damage both softwoods and hardwoods. The larvae of the beetle bore through the wood digesting the cellulose. After about 3 years they form a pupal chamber near the surface and there change into adult beetles. In the summer they bite their way out to the surface, forming the characteristic round flightholes 1.5mm in diameter. After mating, the females lay their eggs (up to 80) in cracks, crevices or old flight-holes. The eggs hatch and a new generation begins a fresh life cycle. The life cycle can be as short as 3 years in damp timber predigested by a wood-rotting fungus. Wood-boring Weevil (Euophryum confine) This is a wood-boring insect somewhat similar in appearance and size to the Common Furniture Beetle. There are over 50,000 species of Weevil and all have long snouts. It also differs in that it will only attack timber which is already decayed by wood-rotting fungi. The Weevil is prolific and is known to have up to two complete life cycles in one year. Its presence may therefore be accompanied by serious structural collapse of timber due to fungal decay. The Weevil prefers sappy earlywood where both adult and larvae tunnel, forming slot-like galleries in the timber and an irregular flight-hole on the surface of about 1.5mm wide. Death Watch Beetle (Xestobium rufovillosum) This wood-boring insect is related to the Common Furniture Beetle, but is much larger. Its flight-hole is large and round (3mm diameter) and its bore dust is coarse and bun shaped. The larvae of this beetle are usually found in decaying oak, and the life cycle from egg to adult can be as short as four years. In dry, sound wood the larvae may tunnel for up to twelve years before pupating. As with most other wood-boring insects, it is the larvae, feeding on the timber, which do all the damage. Eventually the larvae pupate and turn into beetles, which emerge from the wood, mate, and the cycle starts again. The female lays up to 200 eggs. Whilst generally attacking hardwoods only, this wood boring insect has been known to feed upon decaying softwood timbers. The well-known tapping, caused by the head of the beetle is a mating call during the flight season (typically March-June). This insect is often found in churches hence the association with death reflected in its name. House Longhorn Beetle (Hylotrupes bajulus) This wood-destroying insect attacks seasoned softwoods laying its eggs in the cracks and crevices of wood. The eggs hatch out within about three weeks into grubs or larvae. The larvae tunnel through the wood and can eat their own length once a day. Since near maturity they are about 25mm long, the damage caused by these insects can be enormous. After tunnelling for some 4 to 7 years, the adult beetle emerges from the wood during the mating season, leaving the characteristic oval flight-hole which may be up to 10mm long and 6mm wide. After mating, one beetle can lay as many as 200 eggs. In Great Britain this insect is found mainly in Surrey and Hampshire.

6 Specifier Guide A Quick Guide To Specifying Preserved Timber By providing your specialist treater with the appropriate information this will ensure your timber is preserved to the proper specification. The expected service life of timber varies according to the species and use classes. Please check with your specialist treater. Treated products can be produced with the appropriate preservative system to meet a variety of specifications and standards such as the British and European Standards, the Highways Agency and NHBC. Suggested Standard Specification Clause Architects can refer to their NBS standard clauses. To specify Osmose Naturewood and Protim Clearchoice the following wording is recommended. The timber as detailed...(insert timber specification including dimension, species, condition and end use or description of component)...is to be vacuum/pressure treated with a Protim Clearchoice preservative system, to the correct use class for the end use. The timber as detailed...(insert timber specification including dimension, species, condition and end use or description of component)...is to be vacuum/pressure treated with an Osmose Naturewood preservative system, to the correct use class for the end use. You may specify the timber type and the preservative yourself. Some independent treaters offer water repellent & colour dye additives. Treat any cut ends with appropriate cut end preservative. Desired Service Life The desired service life does not provide a guarantee of performance but merely an indication of the expectation against which the recommendations for timber treatment are drawn up, assuming good design and normal conditions of use. Protim Clearchoice is an organic preservation system for wood, pressure treated for use in construction projects that require protection to use classes UC1, UC2 and UC3. When using Protim Clearchoice in external applications it will need to be coated with a suitable external coating which will be maintained in service. Osmose Naturewood is a preservation system for wood that has been pressure treated with an Osmose preservative system which is based on copper and an organic co-biocide (Alkaline Copper Quaternary) that require protection to use classes UC1,UC2,UC3 and UC4. USE CLASS TABLE Use Class (UC) 1 2 3a 3b Use Above ground, covered. Permanently dry, insect risk. Above ground, covered. Occasional risk of wetting. Above ground, coated. Exposed to frequent wetting. Above ground, uncoated. Exposed to frequent wetting. More comprehensive information is available from our Technical Services Department about use classes, timber species and service life. The above is intended as a quick guide only. Please check for specialist applications. Always check for your particular end use if in any doubt. 4 In contact with ground or fresh water. Permanently exposed to wetting. Osmose Naturewood and Protim Clearchoice Treated Wood Products Provide Long-Term Confidence Formulations are applied in accordance with the recent European Standards regime, rather than by using the more traditional British Standards criteria. The following Desired Service Life categories from the BS8417: 2003 therefore apply to Osmose Naturewood and Protim Clearchoice - Components in Use Class 1 & 2 60 years Components in Use Class 3 15 & 30* years Components in Use Class 4 15 & 30* years The figures above are dependent on the particular species being treated *30 years desired service life is a special order process for Osmose Naturewood.

7 The Preservative Process COMPONENT USE CLASS RECOMMENDED TREATMENT A Domestic pitched roofs all structural timber 1 P The timber is transferred into the treatment vessel. A vacuum pulls the air out of the vessel. Osmose preservative fills the vessel. Condensation - risk pitched B roofs - all structural timber 2 P C Tiling / slating battens 2 D Flat roof timbers 2 P E Barge boards, fascia boards 3a F External frame - outer leaf 3 P The vessel is pressurised forcing the preservative into the timber. The preservative is removed and final vacuum is applied. The timber has now been preserved with Osmose preservative. External frame - inner leaf - except G sole plates 2 P H* Frame sheathing - plywoods 2 I External cladding 3 P J Battens for fixing external cladding 2 K First floor joists 1 P L External joinery 3a M Surrounds for non-wood windows 3a N External doors 3a O External door frames 3a P Ground floor joists 2 P Q Sole plates above DPC 2 P R Sole plates below DPC 4 S Decking 3b T Fence posts 4 U Swimming pool surrounds (external) 4 V Timber garden products 3/4 P In these circumstances this treatment is the preferred option. H* Certain grades of plywood can be preserved with please check.

8 Protim Clearchoice A long proven history For over 100 years, The Osmose group of companies has provided a top quality timber preservation service, protecting wood and setting the standards for a premium quality and natural construction material - preserved wood. Wood is a natural renewable construction material Wood is surely the optimum construction material; it is beautiful, environmentally sourced and extremely versatile. Its high strength to weight ratio and insulating properties makes it the ideal material for construction projects such as roof building and timber frame housing. Unprotected wood can also be a source of food for fungi and certain species of insects such as Hylotrupes bajulus, otherwise known as the house longhorn beetle. Therefore it is essential that wood is pre-treated with Protim Clearchoice to ensure full protection against wood boring insects and fungal decay throughout the service life of the project. The Protim pressure treatment system is a tried and trusted method of preserving timber against fungal decay and insect attack for internal and external timbers in above ground applications. Discerning do-it-yourself enthusiasts, professional building contractors and specifiers look to Protim Clearchoice to ensure a premium quality wood preservative that gives durability to pre-treated timber. What is Protim Clearchoice? Protim Clearchoice is a preservation system for wood, pressure treated for use in construction projects that require protection to Use Class UC1, UC2, UC3 (see table) such as roof timbers, timber framing, internal and external joinery and other internal and external timber projects that are above dpc/ground level. When using Protim Clearchoice in external applications it will need to be coated with a suitable external coating which will be maintained in service. USE CLASS TABLE Use Class (UC) Use 1 2 3a 3b Above ground, covered. Permanently dry, insect risk. Above ground, covered. Occasional risk of wetting. Above ground, coated. Exposed to frequent wetting. Above ground, uncoated. Exposed to frequent wetting.

9 Osmose Naturewood The durable choice for all garden timber projects Osmose Naturewood preserved wood is the name given to timber that has been preserved with an Osmose preservative system which is based on copper and an organic co-biocide (Alkaline Copper Quaternary). Colour and Surface Protection To enhance weather protection apply a weather resistant finish. Any exposed wood, preserved or not, should be protected from the weather. Application of a quality clear water repellent or semi-transparent stain will help. To maintain a modern natural look a Deck Oil can be used. Appearance Of Osmose Naturewood Osmose Naturewood products will initially have a green appearance that highlights the natural variations of the wood; this will weather to an attractive natural honey brown colour before finally fading to a driftwood grey after long term exposure to the sun. Osmose Naturewood products can be painted or stained to match any outdoor colour scheme. Always follow manufacturer s recommendations. Alkaline Copper Quaternary systems have provided proven performance for well over a decade in locations throughout Europe, North America, Australia and Japan. Osmose Naturewood preserved wood is pressure treated to use classes UC1, UC2, UC3 and UC4 (see table), and can be used for fencing, timber decking, landscaping timbers and construction timbers. Additives Options Osmose has developed a range of additives for the Naturewood timber protection system. Attractive brown and gold colour additive systems are in use offering end-users a choice of colours for treated wood products, whilst a Water Repellent is available to add value to decking and garden timbers. Preservative Protection Osmose Naturewood preserved wood has been protected using a modern copper based preservative system. Copper, a naturally occurring mineral is an effective and widely used fungicide. USE CLASS TABLE Use Class (UC) Use Osmose Naturewood and Colour Dye Additive Osmose Naturewood and Water Repellent Additive 1 2 3a 3b 4 Above ground, covered. Permanently dry, insect risk. Above ground, covered. Occasional risk of wetting. Above ground, coated. Exposed to frequent wetting. Above ground, uncoated. Exposed to frequent wetting. In contact with ground or fresh water. Permanently exposed to wetting.

10 Osmose Royale Osmose Royale The Osmose Royale Process was originally developed as a drying medium for timber. A blend of mineral and vegetable oils were used under heat and vacuum to remove moisture from wet timber. It was discovered that timber dried by this process benefited from some new unique properties which enhanced its performance. The Osmose Royale Process creates a stabilised building material with many added value opportunities for the timber cladding, fencing and pre-stain decorative timber market sectors. The Osmose Royale Process The timber is placed into a hot oil processing plant and subjected to a controlled combination of vacuum and temperature to initiate moisture removal. The heated blend of Osmose Royale oils is introduced under vacuum into the vessel and this accelerates the moisture removal. The removed moisture is replaced with the Osmose Royale oil. A final vacuum is applied to remove excess Osmose Royale oil and the timber is allowed to dry. Benefits The Osmose Royale process adds performance characteristics to the base product. It is designed to seal, stabilise and protect the timber surface, reducing cracks and surface deterioration caused by the natural swelling and contraction caused by moisture movement in unprocessed wood. The addition of colour creates a pre-finished product that will perform well in external applications, reducing the need for hand application of a coating and costly short term maintenance. Colour and Preservation As a two stage process, the timber is preserved with Osmose Naturewood a modern copper based preservative system. Colour pigments can be added to the Royale oil to give an attractive pre-finished look.

11 Osmose Indurite What is Osmose Indurite enhanced timber? Osmose Indurite is a water based formulation containing a modified natural polysaccharide, similar to the cellulose in timber which has been obtained from the harvest of an annual crop. This polysaccharide has been modified to create a water soluble product that is stable in the formulation and of a critical molecular size able to be impregnated into the timber. Who said nature could not be improved? Global research over the past ten years has resulted in the development of a unique and revolutionary technology which impregnates softwood with an organic cellulose compound giving it the physical properties of hardwood. Using sustainable managed plantations, the Osmose Indurite process can transform softwood right through to the core. The innovative treatment not only hardens the wood but can colour it to the desired finish. Once impregnated (carried out by normal impregnation procedures, such as are used for preservatives) the solids in the formulation reform as natural, rigid, insoluble polysaccharide on curing. The result is an increase in hardness, strength, density, dimensional stability and resistance to fire spread. The hardened wood works, looks and lasts like premium hardwood. Other than the natural polysaccharide and water there are a number of catalysts present that facilitate and regulate the changes that are required of the polysaccharide. Osmose Indurite hardened timber can be used for interior flooring, furniture, doors, windows, panelling/boards and other applications where hardness, strength, dimensional stability and appearance are essential. The Osmose Indurite wood hardening system. Adds value to sustainable softwood timber Looks and lasts like premium hardwood Increase in hardness and strength Improvement in dimensional stability Deep penetration of colour additives an option for permeable species

12 Osmose FirePRO Fire Retardant Treated Wood Products Osmose FirePRO* fire retardant treated wood (FRTW) products are pressure impregnated with an Osmose FirePRO interior high temperature fire retardant chemical formulation based on proprietary Osmose technology. Historically, fire retardants have depended upon phosphorus based compounds to achieve fire performance properties. While the unique Osmose FirePRO chemistry contains no phosphates, independent testing performed in accordance with industry standards has shown Osmose FirePRO FRTW products exhibit fire performance properties without compromising other critical engineering properties such as strength, durability, corrosivity, and hygroscopicity. Application Osmose FirePRO FRTW products are permitted for use in above ground interior applications where the adopted building regulations permit the use of wood products or fire retardant wood products such as: roof systems, cladding, sheathing, joists etc. It can also be used in other interior applications such as exhibition stands. The specifier and/or end user is responsible to review the test data on Osmose FirePRO FRTW products to determine if they are acceptable for the intended end use. The Treatment Process Osmose FirePRO treating solution is applied to timber products in an industrial controlled treatment process using vacuum pressure impregnation, shown below. Osmose FirePRO FRTW products must be Air or Kiln dried after treatment to ensure the properties of Osmose FirePRO are maintained. Osmose FirePRO Standards Osmose FirePRO FRTW products have been tested to BS EN :2002 Fire Classification of Construction Products and Building Elements. These tests are commonly referred to as reaction to fire tests. Reaction to fire tests are commonly called up in regulations in both the building and transport sectors. The classifications of flammability are A1, A2, B, C, D, E and F. The table below gives an overview of the classifications Classification: (European) A1 A2 B Class 0 C D Equivalence to BS476 classification Non combustible Very limited combustibility Class1 Class3 The following species are currently approved: Softwood Plywood Far Eastern Plywood Both commodities have achieved both B and C classifications using different loadings. Osmose FirePRO FRTW products can also be CE marked. Further materials are under going approval. Please ask for the updated list. The timber is transferred into the treatment vessel. A vacuum pulls the air out of the vessel. Osmose FirePRO solution fills the vessel. The vessel is pressurised forcing the solution into the timber. The solution is removed and final vacuum is applied. The timber has now been treated with Osmose FirePRO solution.