Timber grading – Visual stress grading of timber – Visual grading of round timber – Mechanical stress-grading of timber – Examples and advantages of timber grading machines − Design characteristics of structural timber according Eurocode 5 – Bibliography.

Currently, we increasingly need to carry out construction modifications on objects which in view of their age could be basically considered as new-build buildings at which we did not expect such a requirement. In most cases these construction modifications are caused by failures or defects of roofs, especially operation roofs – terraces. The cause of failure is often a combination of several factors. The primary source of error may be already a design project and roofing solution and quality of realization of each roof layer and roof details or unsuitable climatic conditions during the implementation. A separate issue could be the problem of the poor quality of used materials. By interaction of these negative effects then surprisingly arise failures at objects which were realized a few years ago.

This paper deals with the determination of linear thermal transmittance for buildings with rounded shapes. Introduction deals with typlogy and examples of the buildings containing organic shape. Subsequently is described the theory of determination of linear thermal transmittance. It provides information applicable for buildings assessment in engineering practice.

Years of speculation about the correct windows installation finally ends. On May 1^st the new standard ČSN 74 6077 Windows and external pedestrian doorsets - Requirements for installation came into force. It is the very first implementing standard for this branch of construction. The standard is based on the technical standard information TNI 74 6077 and replaces it.

Safeguarding perfect labour safety should be a principal requirement respected by all parties involved in the building process in particular from the point of view of the variety of works performed and complexity of building industry conditions as well as with regard to individual risks endangering life and health of workers during the preparation and performance of construction works. As far as individual entities operating in the building industry (tradesmen, small, medium-sized and big building companies) are concerned, adequate attention to labour safety is usually paid big building companies, only, who have sufficient resources to address this complex issued in a systematic way. It was the difficult economic situation associated with a considerable decline of the building production what has recently forced many building companies to implement significant saving measures that could affect the labour safety, too. The paper should show an apparent link between the economic situation, saving measures and labour safety in the building industry and call attention to apparent risks associated with the circumvention or violation of labour safety rules in order to keep profitability and competiveness of buildings companies.

The article aims to familiarize the reader with the complexity of the issue of the protection of buildings against the effects of water, especially in the liquid state. Waterproofing of buildings, it is not only the protection of roofs, but also the substructure, ie that part of the building, which may, in some cases, be deep underground.
The most important moment is awareness of the fact that meanwhile repairing the roof waterproofing is always accessible, in case of the substructure waterproofing the accessibility is always very complicated and any of its repair is very expensive. From this it follows that the design and use of only one system without the use of other systems, both direct and indirect, is very risky and as such can not be recommended.

An overview of the structural behaviour of notched timber beams. Notching a beam at its end leads to a stress concentration at the corner of the notch due to the sudden change in the notched beam’s cross section. The concentration of tensile stresses perpendicular to the grain and shear and can lead to failure caused by the crack propagation from the notch corner. In addition, a review of the notched beams design according Eurocode 5, reinforcements, and the design example are included.

The contribution deals with particular causes of excessive damp of wooden constructions in objects of the civil engineering. It concerns for instance the matter of water condensation on the surface of wooden elements and on the inside of constructions that contain wooden elements, of incorrect construction design, of constructions with wooden elements and leaking water in places wth wooden elements.

The article deals with the determination of effects of heat radiation on the quality of the indoor environment in winter season, while insulating by double and triple glasses. Effect of radiation through the fillings of the panels and building structures has been evaluated on the basis of knowledge of the mean radiation temperature and operative temperature in the given indoor environment. Isotherms of mean radiation and operative temperatures for different cases of application of insulated glasses having different coefficients of thermal transfer have been presented.

An overview of the development and standard types of the prefabricated wooden houses, their basic structural materials, basic mechanical timber joints, design practice for loads effects and requirements for structural elements is presented in the five-part series. The first part explains the development and standard types of the prefabricated wooden houses.

An overview of the development and standard types of the prefabricated wooden houses, their basic structural materials, basic mechanical timber joints, design practice for loads effects and requirements for structural elements is presented in the five-part series. The fourth part develops an understanding of the design practice for loads effects.

Failures occurring on the facades of assembly houses often arise due to volume changes sunlit walls and incorrectly made contact details between panels. Sometimes it is not enough to eliminate them or repeated repair of damaged joints. Therefore is no choice of other solution than to overlap these joints with thermal insulation system. One such case is the subject of this paper.

This paper deals with the experiment which was used to analyse the influence of duration of cement hydration on the concrete properties. Compressive strength of concrete and dynamic and static values of the concrete modulus of elasticity were determined. The only variable factor was the duration of cement hydration. The outcome has form of graphic and tabular outputs showing the observed values.

The paper deals with the main rules for inclined roofs design from the thermal protection of buildings perspective in the first row. The text follows up the composition of these structures with the respect to the position of thermo insulation layer and in depth discuss the important rules for quality design both individual roof structures layers and whole roof compositions.

An overview of the development and standard types of the prefabricated wooden houses, their basic structural materials, basic mechanical timber joints, design practice for loads effects and requirements for structural elements is presented in the five-part series. In the third part basic mechanical timber joints are dealt with.

By flat roof reconstruction of panel apartment houses we meet quirements for hygiene, health, inerior environment, thermal protection and energy consuption. This paper deal with these problems. There are also mentioned actual conditions of flat roofs and principles of their reconstruction. Moreover paper contains example of wrong reconstruction of panel house.

One of the most discussed questions during the last few decades is the functionality of inverted roofs, with the thermal insulation of low water absorbing extruded polystyrene.
The main question is the one of heat loss caused by the cold rain water penetrating through the joints between the boards of thermal insulation itself and going towards the water outlet system beneath this insulation, respectively directly on the waterproofing. The snow melting period seems as the most serious from this point of view.
Two test sample frames were prepared for the purpose of investigation of this phenomena. One of them simulating the rain water outlet above the roof edge flashing and the second one for the simulation of outlet through the inner roof gully. The ratio of undergoing water in the various roof slopes in condition of artificial rain was measured. The ratio of undergoing water was actually high and that it decreased with the increasing slope, depending also on the scheme of water outlet. In case of installation of standard breathing membrane with the low equivalent diffusive thickness placed in the position of separation layer between the XPS insulation boards and the gravel ballast layer ratio of undergoing water became to be nearly inverted. This breather membrane took the function of certain rain water barrier in the structure.

An overview of the development and standard types of the prefabricated wooden houses, their basic structural materials, basic mechanical timber joints, design practice for loads effects and requirements for structural elements is presented in the five-part series. In the second part basic structural materials are dealt with.

In October 2013 in Orange County Great Park in city of Irvine, California, took place the sixth edition of the prestigious international competition of universities U.S. Solar Decathlon 2013. This round took part also Team Czech Republic from the Czech Technical University in Prague, which finished at overall third place. The article describes in detail building services used in the AIR House.

The article draws attention to situations, which are created when cracks in concrete and reinforced concrete structures are evaluated. Despite cracks being in general allowable in reinforced concrete structures as per ČSN EN 1992-1-1, only the width of cracks must be limited with respect to functionality of the structure. These limits are well defined with respect to water impermeability of reinforced concrete structures or their durability, but we are missing criteria, which would allow for evaluation of influence of the cracks on visual appearance of the structures. Therefore very frequently situation arises, when cracks are not warranty claimed as a potential static defect or a flaw, or as an aspect influencing lifespan of the structure, but solely as an aesthetic defect.