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Steel reinforced concrete: The Japanese perspective on earthquake resistant composite construction
Published in Edmund Booth, Seismic Design Practice into the Next Century, 1998
For long term shear loading the approach is quite different, apparently based on a simplified stiffness approach considering a shear modular ratio of 15 for solid webs of I sections bending about their strong axis, 10 for the flanges of I section bending about their weak axis and 35 for truss type members (which presumably takes account of the difference between the elastic and shear moduli). For long term loading the shear resistance from battens is disregarded.
System housing: timber frame
Published in Derek Worthing, Nigel Dann, Roger Heath, of Houses, 2021
Derek Worthing, Nigel Dann, Roger Heath
Lightweight claddings are normally fixed to timber battens, positioned vertically or horizontally (depending on the cladding material) on top of the breather paper and nailed through the sheathing into the studs. The battens provide for a vented cavity behind the external facing by which water or water vapour can be drained away or can evaporate.
Pitched roofs
Published in Duncan Marshall, Derek Worthing, Roger Heath, Nigel Dann, Understanding Housing Defects, 2013
Duncan Marshall, Derek Worthing, Roger Heath, Nigel Dann
Problems experienced on shingle roofs include the following. Splitting. Older shingles were not pre-holed for nailing, the nails being driven directly into the wood about 150–200mm up from the butt (or bottom). This meant that the shingle could sometimes split when being installed and, if this was a hairline crack, it might not become apparent until later. Modern shingles are often pre-drilled to avoid this problem.Loose or missing shingle. These problems may be caused by the effect of wind lift. Shingles are extremely light in weight and require very careful nailing – it is normal for them to be twice nailed. A more secure and effective fixing is provided by ring-shanked nails, which have larger heads. (See also the next sub-section on nail problems and the later section on nail sickness.)Nail problems. Corrosive acids in both oak and cedar will attack any zinc galvanised steel nail, resulting in ‘nail sickness’ and loss of the shingle. This may be avoided by the use of non-ferrous nails, though there may be some staining from those containing copper or brass. (Zinc gutters, flashings and ridge cappings should also not be used for similar reasons.)Excessive dampness. Earlier reference has been made to the need to treat shingles with preservative in order to prolong durability. Great Britain, particularly the western part, is renowned for its wet climate and any timber roofing material is particularly susceptible. The shingles are secured to battens that traditionally were fixed above an unfelted roof. The modern approach is to install a felt underlay that can restrict air circulation under the shingles and prolong drying out. This may lead to more rapid deterioration of the shingles. In some cases, air circulation and drying out are improved by the installation of counter-battens.Surface deterioration. The exposed surfaces of the shingle will weather and gradually erode over a period of time.Lichen. Lichen may be found on the exposed upper surfaces of the shingles. It grows on the moist timber and, though it does not directly attack the timber, it is unsightly and can adversely affect the efficiency of water run-off, leading to accelerated deterioration of the shingles.Effect upon metals. The water run-off from shingles is acidic in content and this may have a corrosive effect upon any metal gutters and flashings affected. Other materials should be selected for these components, where they come into contact with such run-off.
Method for evaluating the snagging propensity of roofing membranes in buildings by roosting bats
Published in Building Research & Information, 2020
E. A. Essah, S. J. Russell, S. D. Waring, J. Ferguson, C. Williams, K. Walsh, S. Dyer, R. Raynor
Generally, the role and design of buildings has always been to provide protection from the wind, sun, cold, rain and other environmental conditions, which have evolved over many years (Allard & Santamouris, 1998). In the past, building designs were simple and considered these environmental conditions. However, at the end of the 19th century, building construction was modified with increasing complexity and size, to suit growing technological advancement and the change in climate (Loomans, 1998). At present, in the United Kingdom (UK) the most common type of domestic roof construction used is pitched roofs. By design and construction, pitched roofs include a system of structural elements usually made from timber which provide support to an impermeable or breathable underlay. Over the underlay, tiling battens are nailed directly to the structural elements, providing support and a fixing point for a slate, concrete or clay tiles creating spaces between battens and membranes.