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The transparency of wood to microwave radiation is subject to changes in the wood's properties caused by softening of the wood material during fungal attack or the addition of moisture. A prototype microwave system that measures microwave attenuation and phase delay between two antennae was developed to detect fungal decay in wood at equilibrium moisture content. A total of twelve wooden stakes of 200 x 65 x 65 mm Pinus radiata (softwood) and twelve stakes of Eucalyptus regnans (hardwood) of the same dimensions were exposed to soil containing decay fungi for 12, 16, 20 and 24 weeks in an Accelerated Field Simulator (AFS), which is a climate conditioned room that simulates humid tropical conditions. A control set of three stakes of each wood type was also included in the experiment. Samples were washed and dried in an oven before testing with the prototype system. Orienting the antennae such that the microwave field was perpendicular to the wood grain could not distinguish between sound and decayed wood; however orienting the antennae so that the microwave fields were parallel to the wood grain and having the antennae pressed against the wood sample easily distinguished between sound wood and decayed wood. The phase delay data could not distinguish between sound or decayed wood.

Discusses the means and methods of detecting timber decay and damp, briefly outlining the historic use of wood in the construction of dwellings and the role of the timber infestation surveyor. Details the process of a thorough inspection, both external and internal, suggesting that particular note should be taken of high earth or path levels, gaps round window frames, broken guttering, rainwater spillage, cracked renderings, missing slates, defective linings and blocked outlets in gutters, blocked airbricks and sagging roof tiles. Concentrates on fungal and insect damage and stresses the results of dampness. Discusses the importance of thoroughness.

Points to the decline of “craftsmanship” as a factor leading to the demise of the ability to control timber decay in an environmentally‐friendly fashion. Considers pesticides and other chemical‐based treatments as a lower‐cost, relatively recent, but often unsuccessful remedy to timber decay. Outlines major timber‐decay problems: dry rot, wet rot and woodboring insects, and their detection techniques. Includes diagrams and detailed discussion on remedial treatments. Concludes that timber decay cannot be effectively treated without an understanding of the interaction of the external environment, building materials, design and content, and the activities within and occupants of a building, and that manipulation of a single variable (timber decay organisms) is bound to be unsuccessful without such understanding.

Since the time of primitive man, timber has remained the most useful and versatile of all naturally available materials. Its obvious aesthetic value makes it irreplaceable in the manufacture of fine musical instruments, furniture and great works of sculpture, but its greatest use is in the construction of our dwellings. Whether used in its almost natural state to construct a forester's log cabin, or sliced up into convenient pieces to build most of the world's homes, it is unsurpassed for versatility, ease of working and mechanical strength.

This paper aims to identify the most common fungal species that grow on paper manuscripts and cause bio-deterioration. It also detects the impact of additive materials on fungal degrading and builds a wide database. Thus, it helps conservators understand this phenomenon.

In total, 15 samples were collected from different paper manuscripts suffering from fungi. The achievement of the study objectives depends on using a variety of analyzes, such as a microbiological study, which indicated that three main fungi grew on the paper samples. Then, a digital microscope and an environmental scanning electron microscope were used to detect the effect of fungi on paper fibers. Fourier transform infrared microscopy was used to identify the binding medium and the X-ray diffraction method was used to measure the crystallinity index of cellulose of the paper samples.

Arabic gum was used as a binder medium with the samples. Aspergillus Niger, Aspergillus Fumigatus and Aspergillus Clavatus were the most common fungal species that grew on the Qur’an papers under investigation. They also caused much common damage to the paper samples. The results of the analyzes also showed that the highest crystallinity index of cellulose was in the samples that contained the lowest rate of fungal growth.

This paper highlights the relationship between fungal degradation and the multi-component nature of paper manuscripts. It builds a wide database that correlates the composition and the degradation of the Qur’an papers.

Millions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the effect of insulating such floors. Upgrading floors changes the void conditions, which might increase or decrease moisture build-up and mould and fungal growth. The purpose of this paper is to provide a review of the current global evidence and present the results of in situ monitoring of 15 UK floor voids.

An extensive literature review on the moisture behaviour in both uninsulated and insulated suspended timber crawl spaces is supplemented with primary data of a monitoring campaign during different periods between 2012 and 2015. Air temperature and relative humidity sensors were placed in different floor void locations. Where possible, crawl spaces were visually inspected.

Comparison of void conditions to mould growth thresholds highlights that a large number of monitored floor voids might exceed the critical ranges for mould growth, leading to potential occupant health impacts if mould spores transfer into living spaces above. A direct comparison could not be made between insulated and uninsulated floors in the sample due to non-random sampling and because the insulated floors included historically damp floors. The study also highlighted that long-term monitoring over all seasons and high-resolution monitoring and inspection are required; conditions in one location are not representative of conditions in other locations.

This study presents the largest UK sample of monitored floors, evaluated using a review of current evidence and comparison with literature thresholds.

Discusses the forms of decay that can affect oak heartwood, sapwood and wet oak. Examines white rot fungi and brown rot fungi, in particular the way in which they attack oak, giving photographic examples of various types of attack. Considers which forms of rot have structural significance for buildings.

This study aims to use whiteness (WI) and yellowness indices (YI) that were calculated from the International Commission on Illumination (CIE) color parameter to evaluate the efficiency of some triazole fungicides [propiconazole (C₁₅H₁₇Cl₂N₃O₂) and tebuconazole (C₁₆H₂₂ClN₃O)] to protect wooden artifacts from fungal deterioration.

Archeological wooden samples were collected from some historical Islamic buildings in Cairo, Egypt. Three species of fungi were identified in previous work. Propiconazole and tebuconazole with different concentrations treated the infected wooden samples aged for different periods. WI and YI of studied samples were measured using UV spectrophotometer. Calibration and uncertainty estimation accompanied by color measurement were studied.

Studying the uncertainty sources of diffuse reflection of the standard white tiles revealed that the uncertainty of calibration for both the spectrophotometer and white tiles had the highest contribution. The treated samples with tebuconazole and propiconazole fungicides gave good resistance against fungal deterioration at 0.50% for WI and YI.

This study presents the importance of colorimetry in the conservation field because they are considered one of the most important criteria to evaluate conservation materials. From color measurements and their uncertainties, it became clear that triazole fungicides have good efficiency in the protection of wooden artifacts from fungal deterioration. The value of this study is that propiconazole and tebuconazole fungicides at 0.50% can be applied to archaeological wood that is endangered to improper conditions, especially in the case of high levels of relative humidity.

Past and current uses of chemical treatments to control or eradicate fungal infections and/or insect infestations in buildings have led to a number of reported cases where occupants and users of these buildings have suffered various physical symptoms. The role of chemical treatments, whether as biocides, fungicides, insecticides or wood preservatives, has therefore come under scrutiny and various countries are now reviewing their use in favour of a more benign approach to the management of decay in buildings. Growing concern for the environment and the health of those treating or living in treated buildings has also led to changes in the way we perceive and deal with buildings and building defects. As a result, the conventional approach to survey, defect diagnosis and remediation has to be re‐thought and placed in the context of a wider environmental agenda. This paper provides evidence for how historic chemical treatments can have effects on the health of the building and its occupants, and considers the implications of such treatments for those charged with specifying or undertaking works to the fabric of affected buildings.

Whilst the overall need to conserve energy is generally accepted, the importance of undertaking a detailed survey before the start of any insulation work in existing buildings is seldom recognised.