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Cover image: Gettyimages/Katsumi Murouchi

CONTENTS

Preface

Acknowledgements

About the Author

1 Wood Durability and Lifetime of Wooden Products

1.1 Basic information about wood structure and its properties
1.2 Types and principles of wood degradation
1.3 Natural durability of wood
1.4 Methods of wood protection for improvement its durability
1.5 Service life prediction of wooden products
References

2 Abiotic Degradation of Wood

2.1 Wood damaged by weather factors
2.2 Wood damaged thermally and by fire
2.3 Wood damaged by aggressive chemicals
2.4 Properties of abiotically damaged wood
References

3 Biological Degradation of Wood

3.1 Wood damaged by bacteria
3.2 Wood damaged by fungi
3.3 Wood damaged by insects
3.4 Wood damaged by marine organisms
3.5 Mechanisms of wood biodegradation
3.6 Properties of biologically damaged wood
References

4 Structural Protection of Wood

4.1 Methodology of structural protection of wood
4.2 Selection of suitable wood materials
4.3 Design proposals for permanently low moisture of wood
4.4 Fire sections and other fire-safety measures
References

5 Chemical Protection of Wood

5.1 Methodology, ecology and regulation of chemical protection of wood
5.2 Preservatives for wood protection
5.3 Technologies of chemical protection of wood
5.4 Chemical protection of wooden composites
References

6 Modifying Protection of Wood

6.1 Methodology, ecology and effectiveness of wood modification
6.2 Thermally modified wood
6.3 Chemically modified wood
6.4 Biologically modified wood
References

7 Maintenance of Wood and Restoration of Damaged Wood

7.1 Aims and enforcement of the maintenance and the restoration of damaged wood
7.2 Wood maintenance
7.3 Diagnosis of damaged wood
7.4 Sterilization of biologically damaged wood
7.5 Conservation of damaged wood
7.6 Renovation of damaged wood
References

Index

EULA

List of Illustrations

Chapter 1

Figure 1.1 Structural levels of wood (modified from Eriksson et al. (1990) and Reinprecht (2008))
Figure 1.2 The basic types of wooden composites: (1) glulam (glued joints); (2) prefinished wood (coatings or foils); (3) wood–plastic (fibre reinforcement); (4) fibreboard (dispersion systems); (5) particleboard (macro-dispersion systems); (6) plywood (laminated systems); (7) impregnated wood (penetrations or diffusions). (Note: composite is a multicomponent system of materials consisting of at least two macroscopically distinguishable phases, of which at least one is solid)
Figure 1.3 Biological and abiotic wood-degrading factors
Figure 1.4 Estimated service life (ESL_WP) of wooden uncovered bridges is ∼40–50 years when using suitable design for rainfall drain and at the same time also chemical protection of wood elements, either with creosote (a) or with inorganic biocide fixable in wood (b); examples are from Norway (Reinprecht, 2008)

Chapter 2

Figure 2.1 Scheme of factors causing weather impact on wood and their effect on changes in wood
Figure 2.2 Cyclic sequence of damaging processes during atmospheric corrosion of wood in external environment (modified from Feist (1990))
Figure 2.3 Plastic texture of the surface of weathered spruce wood
Figure 2.4 Plastic structure of the surface of weathered spruce plywood arising from the orientation of the annual rings in the top veneers (TR: tangential–radial; R: radial)
Figure 2.5 Energetic (exo: exothermic; endo: endothermic) effects upon thermal decomposition of wood and its components
Figure 2.6 Thermal decomposition of cellulose in pyrolysis, and the burning phase (modified from Shafizadeh (1984))
Figure 2.7 Thermal decomposition of lignin with production of charcoal (modified from Blažej and Košík (1985))
Figure 2.8 Combustion triangle of wood burning
Figure 2.9 Basic mechanism of wood burning
Figure 2.10 Thermal decomposition of wood and its burning depend upon the supply of heat, air flow and presence of inorganic additives in wood (modified from Shafizadeh (1984)): (A) preference for the production of charcoal; (B) preference for the production of flammable gases
Figure 2.11 Wood trusses damaged by a fire – charcoal on wooden elements
Figure 2.12 Basic scheme of the individual fire phases
Figure 2.13 Impact of inorganic fire retardants on the thermal and chemical degradation of cellulose (modified from Le Van (1984)). Note: cellulose modified by fire retardants is dehydrated at temperatures up to 300 °C, when it carbonizes and shows greater decreases in weight than unmodified cellulose does
Figure 2.14 Impact of aggressive chemicals (HCl, HNO₃, H₂SO₄, CH₃COOH, NaOH, NH₄OH, H₂O₂) on rate of chemical corrosion of selected woods (spruce, pine, beech, oak) at 20 °C for 30 days (modified from Reinprecht (1988, 1991))
Figure 2.15 (a) Wood ageing under aerobic conditions – fungal rot and other decay; (b) scheme of wood fossilization under anaerobic conditions – mineralization and carbonization (modified from Fengel (1991))
Figure 2.16 Model of mineralization of lumens and cell walls of wood (modified from Furuno et al. (1986))
Figure 2.17 Impact of the weight loss of thermally–chemically loaded maple (Acer pseudoplatanus) wood on the reduction in its rigidity: MOE_D: dynamic modulus of elasticity; MOE_S: static modulus of elasticity in bending (Reinprecht et al., 1996)
Figure 2.18 Impact of humidity on compression strength in parallel with grains of 8150-year-old subfossil oak found 16 m underground in Gabčíkovo near the Danube river and recent oak (Horský and Reinprecht, 1986)

Chapter 3

Figure 3.1 Bacillus subtilis bacteria intentionally degraded margo and released torus in a bordered pit of a tracheid in the sap-zone of Norway spruce wood (Picea abies)
Figure 3.2 Overview of bacterial decomposition of wood cell wall – erosion bacteria, tunnelling bacteria and cavitation bacteria
Figure 3.3 A scheme of the creation of asci (sacs) with ascospores in fungus from the Ascomycota phylum
Figure 3.4 Fruiting body of Basidiomycota with a hymenophore (a) and a scheme of the creation of basidiospores on basidia in a hymenphore (b). (a) The capped fruiting body with a leaf-shaped hymenophore and a cross-section with a double-sided layer of hymenia containing basidia with basidiospores. (b) The creation of basidiospores in a hymenophore:
Figure 3.5 The creation of conidia on conidiophores of some moulds: (a) Penicillium cyclopium; (b) Aspergillus niger; (c) Paecilomyces variotii; (d) Trichoderma viride
Figure 3.6 Limit moisture conditions in spruce wood with density ρ_o = 350 kg/m³ for activity of decay-causing fungi, with the specification of w_crit.min and w_crit.max. Note (all values in volume%): M_o, amount of wood in the oven-dry state; M_w, amount of wood containing bounded water; V, air; W_h, bounded water in cell walls; W_k, free water in lumens of cells; W, total water; L, lumens filled with air and/or free water
Figure 3.7 Wood cells damaged by brown rot: (i) cell walls exist in a very high degree of decay, and they are significantly thinned (a, b); (ii) crystalline cellulose is totally broken down in libriform elements, while it is retained in vessels and parenchyma cells (b). (Fig. 3.7a) Scanning electron micrograph showing 63.8% weight loss in beech wood Fagus sylvatica attacked with fungus Serpula lacrymans. (Fig. 3.7b) Polarized-light microscopy image showing 68% weight loss of Liquidambar styraciflua wood attacked with fungus Poria placenta
Figure 3.8 Wood cells damaged by white rot. (a) Scheme of cell wall delignification (left) and erosion (right). (b) Erosion of cell walls of beech wood F. sylvatica due to fungus Trametes versicolor, shown for its weight losses 20.6% (b-1) and 41.8% (b-2)
Figure 3.9 Wood cells damaged by soft rot
Figure 3.10 Wood-decaying fungi of primary importance in Europe acting in exteriors on conifers – softwoods
Figure 3.11 Wood-decaying fungi of primary importance in Europe acting in exteriors on broadleaves – hardwoods
Figure 3.12 Wood-decaying fungi of primary importance in Europe acting in buildings
Figure 3.13 Micro-hypha of the wood-staining fungus can impair even the cell wall at the apex by mechanical pressure, and then it is able to grow into the adjacent wood cell
Figure 3.14 Ontogenesis of insects with a complete metamorphosis (holometabolism) (egg, larva, pupa, imago)
Figure 3.15 Limit and optimum moisture conditions in wood for development of wood-borer larvae (modified from Dominik and Starzyk (1983), based on Becker (1950))
Figure 3.16 Long-horned beetles attack wood: (a, b) in interiors; (b–d) logs, sawn timber and wooden products exposed in exteriors (modified from Novák et al. (1974), Dominik and Starzyk (1983) and Reinprecht (2008))
Figure 3.17 Anobiid beetles, damaging built-in wood (a–d) or attacking just non-barked wood (e)
Figure 3.18 (a) European lyctus beetle, Lyctus linearis Goeze, and (b) its circular flight holes from oak wood
Figure 3.19 Giant wood wasp, Urocerus gigas L
Figure 3.20 Typical labyrinth damage of early conifer-wood (b) by wood-damaging ants (a)
Figure 3.21 Tunnel damage of wooden beam by termites (a) and termite soldier in a gallery (b)
Figure 3.22 Wooden pier damaged by marine organisms
Figure 3.23 Wood damaged by Teredo navalis
Figure 3.24 Enzymatic hydrolysis of cellulose by means of (C_X/C₁) endo-/exo-glucanases cooperation and 1,4-β-glucosidase
Figure 3.25 Non-enzymatic oxidation decomposition of cellulose by means of Fenton reagent, Fe²⁺ + H₂O₂ → Fe³⁺ + OH⁻ + OH^·
Figure 3.26 Fundamental principles at biochemical decomposition of lignin, cellulose and xylane in wood; CBQ: cellobiose:quinone oxidoreductase; XBQ: xylobiose:quinone oxidoreductase

Chapter 4

Figure 4.1 Zones with higher risks of moisture penetration to a building with the subsequent damage of wooden elements by wood-damaging fungi and insects: (1a) rainwater; (1b) splashing rainwater; (1c) rainwater entering through the chimney; (2) capillary water; (3) diffusion and condensation water; (4) water enteric by hydrostatic pressures; (5) hygroscopic water; (6) water from damaged pipes, radiators, and so on
Figure 4.2 Typical moisture contents of wood at various locations of a residential house
Figure 4.3 Cracking should be prevented by correct cutting of round wood; there should be no central pith in the elements with greater dimensions since it is usually the cause of the creation of large cracks (a), or the pith should be cut through (b, c) or cut out (c)
Figure 4.4 Euro-beam – a window profile made of bonded wood lamellae has a great dimensional stability and resists cracking better than a massive beam does
Figure 4.5 Faces of wooden construction protected against rainwater using a shelter
Figure 4.6 Faces of a wooden fence may be partially protected against rainwater by using an inclined cut
Figure 4.7 Grooves on the back side of a wooden panelling prevent its deformation and cracking as a result of climatic changes
Figure 4.8 Paints adhere better to a rounded edge of a wooden element (b) than to a sharp edge (a)
Figure 4.9 Correct orientation of ‘tongue and groove’ joint towards the direction of prevailing winds with rainwater in the case of vertically placed wooden panelling
Figure 4.10 Correct (a) and incorrect (b) location of ‘tongue and groove’ joints towards the direction of rainwater in the case of horizontally placed wooden panelling
Figure 4.11 Roof overlap and height of concrete or rock bases affect the intensity of rainwater on wooden panels and facade elements (windows and doors) – see the sufficient roof overlap
Figure 4.12 Old craftsmen have long known that the bottom side of a wooden panel should cover the hydro-insulation crevice between the base and wooden log-cabin construction
Figure 4.13 Geometry of lining of a roof window above a radiator will prevent (a) or will not prevent (b) condensation of water
Figure 4.14 Heads of wooden elements must remain permanently vented; for example, it is necessary to leave at least 50 mm air gaps between the head of a beam and the masonry
Figure 4.15 Air gap between the bottom part of a wooden product or construction (e.g. wooden pole) and the terrain should a minimum of 150–300 mm
Figure 4.16 Correct ventilation of a three-layer roof will prevent an increase in moisture of wooden elements and insulation materials in the roof
Figure 4.17 Air ventilation gap between the facade panel and bearing wall of a wooden construction

Chapter 5

Figure 5.1 Methodology of the chemical protection of wooden structures (in accordance with EN 351-1)
Figure 5.2 Acute toxicities LD_{50 (orally rats)} of some biocides for wood protection
Figure 5.3 Historic development of biocides (fungicides and insecticides) for wood protection
Figure 5.4 Classification of hormonal insecticides – insect growth regulators
Figure 5.5 The fire-stop effect of intumescent paint: the layer of solid carbonized foam (a) above the surface of undamaged wood (b)
Figure 5.6 Coatings on new spruce shingles were already damaged after 2 years due to a high wood moisture before painting
Figure 5.7 The simplest transport of preservatives into model cylindrical capillaries of wood: (a) due to a capillary pressure in an empty capillary; (b) due to a concentration gradient in a capillary filled with water or other solvent (Reinprecht 2008)
Figure 5.8 Nonlinear (usually exponential) increase of the depth of penetration l, the retention R, the surface retention SR, and I_R (equal to PFR – see Section 6.1) of the preservative into the wood during the impregnation process, and specification of the optimal impregnation time τ_opt
Figure 5.9 Technology of wood treatment by immersion or dipping in a stationary dip-tank (a) and by discontinuous spraying (b)
Figure 5.10 Panel impregnation of log-cabin wall: (1) top tank of preservative; (2) porous cloth; (3) vapour-impermeable foil (e.g. polythene, poly(vinyl chloride)); (4) pressing bar; (5) lower tank of preservative
Figure 5.11 Bandage for local chemical protection of a wood column: (1) penetration of water; (2) evaporation of water; (3) bandaging
Figure 5.12 Cartridge with biocide inserted into a risky L-joint of a wooden window
Figure 5.13 Autoclave station for vacuum–pressure impregnation of wooden products
Figure 5.14 Basic technologies for impregnation of air-dried wood: (a) VAV; (b) VPV – Bethell; (c) PV – Lowry; (d) PPV – Rüping
Figure 5.15 Scheme of filling of lumens of cells of wood in the VPV (Bethell) and PPV (Rüping) technologies – that is, prior to evacuation of creosote from the autoclave (stage ‘A’) and after evacuation of creosote from the autoclave (stage ‘B’)
Figure 5.16 Pulse pressure–diffusion technology with changing of increased pressure and vacuum stages, used for impregnation of wet wood with water-soluble preservatives
Figure 5.17 The positive and negative synergy when transforming initial good and bad properties of the basic components (A and B) of a wooden composite into its final properties (C₁ (preferred), C₂, C₃, C₄)
Figure 5.18 Wood particles in various degrees of disintegration prepared for chemical protection
Figure 5.19 Application of preservatives to a wooden composite during its production: initially to the adhesive (a) and another additive (b), or to the mixing drum (c)

Chapter 6

Figure 6.1 Scheme of the ThermoWood production
Figure 6.2 An increase in the durability of pine sapwood thermally modified at 100–240 °C – that is, a reduction in its relative loss of weight when undergoing fungal decay in comparison with untreated wood
Figure 6.3 Resistance of Plato spruce-wood to fungal decay compared with untreated woods
Figure 6.4 Bending strength MOR (a) and stiffness MOE (b) of untreated woods and of the same woods after thermal modification by the Plato process
Figure 6.5 Location of substances in cells of wood at the passive (I., II.a) and active (II.b, II.c) chemical modification processes
Figure 6.6 Weight losses Δm of esterified fibreboards due to 16 weeks' action of the brown-rot fungus Gloeophyllum trabeum. Esterification agents: AA, acetic anhydride; PA, phthalic anhydride; MA, maleic anhydride; OSA, 2-octen-1-yl-succinic acid anhydride; MA+G, maleic anhydride and glycerol; SA, succinic acid anhydride
Figure 6.7 Effect of UF and MF resins at improving selected properties of rotten beech wood Fagus sylvatica

Chapter 7

Figure 7.1 Changes in the density profiles of Norway spruce wood as a result of rot caused by the white-rot fungus Trametes versicolor – detected on samples with a thickness of ∼4 mm in the longitudinal direction using γ-ray densitometry
Figure 7.2 Detection of decay and other damages in Norway spruce utility pole using CT analysis together with Resistograph profile analysis (see Section 7.3.2.7) (Reinprecht, unpublished results)
Figure 7.3 Fractometer – a manual tool for ascertaining the bending characteristics of wood
Figure 7.4 Resistograph – scheme of device, its operation and record of decreased resistance of rotten wood to the penetration of the drill bit (a), and an example of its use for analyses of biological damage in a wooden wall of the historical church in Trnovo (b) together with application of the ultrasonic device Pundit (c)
Figure 7.5 Identification of selected fungi from Trametes genus using PCR–restriction fragment length polymorphism technique with two restriction enzymes: BsuR1 (B) and Hinf1 (H): 1, Trametes versicolor; 2, Trametes pubescens; 3, Trametes sauveolens; 4, CTB 863 A (s.v.)
Figure 7.6 The dendrochronology of fir wood for the territory of the Czech Republic – a standardized reference chronology can be prepared based on identical, minimum increments of fir wood from various areas in the monitored climatic zone
Figure 7.7 Sterilization of a wooden truss using hot air at 100–120 °C (a) from a heat generator (b)
Figure 7.8 Sterilization of oak elements in the articular UNESCO church in Hronsek, Slovakia (a) by microwave heating eliminating larval activity of wood-worm beetle (b)
Figure 7.9 Radiation chamber with a ⁶⁰Co radioisotope for sterilization of wooden items in the Museum of Central Bohemia in Roztoky, Prague, Czech Republic
Figure 7.10 Micro-distribution of UF resin in treated lime-tree (Tilia cordata) wood: (a) cell wall saturation method (the use of non-catalysed UF resin); (b) the lumen filling method (the use of highly catalysed UF resin)
Figure 7.11 Polychrome sculpture from lime-tree wood damaged by galleries of wood-worm beetle and by brown rot (a), and consolidation of this sculpture by polyacrylate Solakryl BT 55, which strengthened and joined deteriorated wooden elements and dust in galleries (b, c)
Figure 7.12 Drawing documentation (a) and photo-documentation (b) from diagnosis of one wooden ceiling, together with marking (c) the biological damage type (BR: brown rot; WG: wood-worm galleries) and level (1: light; 2: medium; 3: strong; 4: total)
Figure 7.13 Renovation of the wooden church in Hunkovce – replacement of significantly bio-damaged beams with new ones was carried out by disassembling the log-cabin walls (a) and less-damaged beams were returned to the structure (b)
Figure 7.14 A wooden beam reinforced using the splicing method: (a) reinforcement using two wooden splices on the sides of the beam; (b) reinforcement using one steel splice on the side of the beam; (c) reinforcement using wooden splices in the central zone of the beam. (1: beam; 2: wooden splice; 3: nail; 4: bolt; 5: steel splice)
Figure 7.15 Wooden beam reinforced at the top using a layer of polymer concrete (1: beam; 2: polymer concrete; 3: temporary facing with a separation foil)
Figure 7.16 Methods (a, b) for anchoring ceiling joist with a rotten or cut head into classical steel brackets (1: ceiling joist; 2: steel bracket; 3: bolt; 4: concreting a bracket into masonry)
Figure 7.17 Repair of ceiling joist with a rotten head using a monolithic stainless steel bracket (1: upper holding board; 2: lower holding board; 3: horizontal load-bearing board; 4: offcut of rotten ceiling joist; 5: piece of wood for covering the bracket at the bottom (e.g. veneer); 6: new timber attached to the end of the bracket with bolts, and then the fixing points are covered with wooden inserts; 7: hole for bolt; 8: wooden insert for masking of bolt)
Figure 7.18 Carbon lamellae used for reinforcing a wooden beam (1: lamellae from carbon fibre; 2: veneer identical in texture and colour to the wooden beam)
Figure 7.19 Prosthesis of wooden elements using typical carpentry joints: (a) straight plated joint (e.g. for elements under compression stress); (b) oblique plated joint (e.g. for elements under bending stress); (c) wedged inclined plated joint (e.g. for elements under tension, bending or compression stress); (d) wedged plated joint (e.g. for elements under bending stress in two directions); (e) scissor plated joint (e.g. for elements under compression stress and side movement stresses); (f) cross-plated joint (e.g. for elements under buckling stress)
Figure 7.20 Local repair of a ceiling beam with a rotten head using the ‘beta’ system; that is, with a prosthesis consisting of epoxy resin, polymer concrete and reinforcing rods. (a) Side view of a substituted head of a ceiling joist. (b) Top view of the substitution method. First, the weakened zone of the wood is impregnated using low-viscosity epoxy resin; second, connecting bars are inserted into drilled openings in the remaining part of the wooden element covered with epoxy resin; third, the cavity in wood in the space of a total rot is filled with epoxy polymer concrete (1: perforated separating foil; 2: cavity (e.g. rotten beam head) replaced with epoxy resin or polymer concrete; 3: reinforcing rod of carbon fibres; 4: healthy wood; 5: damaged weakened zone in the wood; 6: new oak wood/pad and splice; 7: ventilating support; 8: masonry)
Figure 7.21 Examples of substituting the damaged head (a) or middle section (b) of the wooden element using the ‘beta’ system (1: reinforcing rod; 2: polymer concrete; 3: epoxy resin; 4: renovated wooden element)
Figure 7.22 Sealing of an unevenly damaged wooden element (1: weakened zone of wood impregnated with epoxy resin, 2: inserted piece of new wood wrapped in a layer of putty from all sides)
Figure 7.23 Support of ceiling joists with damaged heads using a steel girder
Figure 7.24 Temporary support of a damaged purlin using two supporting columns (1: purlin; 2: joining beam; 3: column; 4: supporting column)
Figure 7.25 Suspending a damaged ceiling joist on a transverse beam placed on neighbouring, healthy ceiling joists (1: ceiling joist with a damaged and cut head; 2: transverse beam; 3: steel rod)
Figure 7.26 Bracing of rafter with joining beam when the full gusset in truss is weakened (1: joining beam; 2: rafter; 3: bracing boards; 4: backing plate)
Figure 7.27 Strengthening a wooden truss using additional elements: (a) original truss; (b) strengthening of rafters using a roost; (c) supporting of rafters with inclined braces; (d) supporting of rafters with columns, close to the joining beam support
Figure 7.28 Tightening a wooden truss using a steel rod with an adjustment component (1: adjustment component; 2: steel rod welded to the steel reinforcement in a concreate ceiling and mounted to the wood rafter)
Figure 7.29 A stretching system for reinforcing a wooden beam (1: wooden beam; 2: steel cable)
Figure 7.30 Interlinking of wooden ceilings with a concrete plate (a) or with an additional layer of new boards (b) (1: ceiling joist; 1′: attic beam; 2: steel means of anchoring to the concrete; 2′: screw to the wood; 3: wooden skeleton; 4: concrete plate; 5: layer of new boards)

Preface

It is well known that wood has been used since ancient times as a structural material for buildings, as the main or auxiliary material in agriculture and later in industrial products, and as a material for furniture and various artistic products.

The service life of wooden products depends first of all on the natural durability of the wood species and wooden composites used, but also very significantly on their design, their methods of chemical and modifying protection, their exposure and their maintenance.

People are able to prolong the lifetime of wooden products based on practical knowledge related to wood-damaging agents (e.g. solar radiation, water, fire, aggressive chemicals, wood-decaying fungi, moulds, wood-destroying insects or marine borers), and also from theoretical studies related to the mechanisms of their action on wood at the molecular, anatomical, morphological and geometry levels.

The structural protection of wooden products is based first of all on the application of durable wood species and other high-quality materials. Simultaneously, the presence of wood-damaging agents has to be limited by using suitable designs with the aim to reduce contact with rain and other sources of water, to reduce the creation of water condensate, and to reduce the impact of ultraviolet (UV) light and fire. So, for this purpose, suitable atmospheric, moisture-impermeable, UV and fire-retardant insulations are applied.

Chemical protection of wood is performed with preservatives; that is, mainly with fungicides, toxic and hormonal insecticides, fire retardants and UV-protective finishes that are applied on the wood's surface and also into its depth. Currently, for wood preservatives not only is their efficiency important, but also their effects on human health and the environment. The optimization of wood pretreatment (e.g. debarking, drying, improving permeability) and its chemical preservation technology (e.g. time of dipping, vacuum, and/or pressure) derive from the theoretical principles of flow and diffusion of preservative substances in the capillary structure of wood. Plywood, particleboards and other wooden composites can be chemically treated during their production or subsequently.

The modifying protection of wood is a prospective mode for improving its resistance against biological agents and dimensional changes. Using active chemical modification, the –OH groups of the lignin–saccharide wood matrix react with molecules of a suitable chemical. This results in a decrease in wood hygroscopicity, and fungi, insects or marine borers then have less interest in this treated wood (e.g. acetylated wood). Thermally modified wood also leads to good resistance to atmospheric factors and biological damage, mainly where there is no contact with the ground.

Wooden products have to be regularly maintained with the aim to increase their lifetime. However, when they became damaged, a thorough inspection of their actual state is important; that is, the diagnosis of the cause, type, degree and range of their damage. Biologically damaged wood should be sterilized. Subsequently, for restoration of smaller wooden elements are used conservation methods, working with natural and synthetic substances. Load-bearing elements of wooden houses, roofs, ceilings and other constructions can be reinforced with prostheses, splicing, special bracing or other methods.

Acknowledgements

The writing of this book was inspired by Mr Gervais Sawyer, editor of the International Wood Products Journal. At the same time I would like to thank the professional members of the Wiley publishing house, personally to the publisher Mr Paul Sayer for finding external examiners and for his important comments, to all the anonymous reviewers for ideas on improving some sections of this book, to the editorial assistant Ms Viktora Vida for painstaking collection and control of individual chapters, to Mr Peter Lewis for careful copyediting work and preparing the manuscript for typesetting, and to the production editor Ms Audrey Koh and the project manager from Aptara Ms Baljinder Kaur for creation of the proofs and stylish press quality files. Finally, I would like to thank my daughter Mrs Judita Quiňones for her help in the first grammar correction of this book.

Ladislav Reinprecht

Zvolen, December 2015

About the Author

Ladislav Reinprecht is a professor at the Faculty of Wood Sciences and Technology, Technical University in Zvolen, Slovakia. He obtained an MSc degree in organic chemistry, a postgraduate degree in mycology and a PhD degree in wood technology. For students and specialists he has written many books and monographs, both in Slovak (e.g. Wood Protection, Processes of Wood Deterioration and Modification, Reconstruction of Damaged Wood Structures, Wooden Buildings – Constructions, Protection and Maintenance, Wooden Ceilings and Trusses – Types, Failures, Inspections and Reconstructions), and in English (e.g. Strength of Deteriorated Wood in Relation to its Structure, TCMTB and Organotin Fungicides for Wood Preservation). His primary research interest lies in the analysis of abiotic and biological defects in wood structure – the conditions for their creation and the methods of their detection, inhibition and prevention. He has published the results of his experimental work in many articles in scientific journals and presented results at various international and domestic conferences.

Wood Deterioration,
Protection and
Maintenance

Ladislav Reinprecht

Faculty ofWood Sciences and Technology,
Technical University of Zvolen, Slovakia

Preface

Acknowledgements

About the Author

Ladislav Reinprecht Faculty ofWood Sciences and Technology, Technical University of Zvolen, Slovakia

Acknowledgements

Ladislav Reinprecht

Faculty ofWood Sciences and Technology,
Technical University of Zvolen, Slovakia