Roof construction with mechanically anchored waterproofing sheets rightfully belongs to the most popular solution of roof structure not only in the industrial but also civil and residential construction. This is because of the speed of construction, small depending on weather conditions and often lower financial cost. But vera often there are lot of mistakes in this part of construction design.
The media regularly appear alarming reports, according to the Czech Republic gets into trouble with the fulfillment of its obligations towards the EU, due to the lack of state financial support. This information is frequently based on calculations originating from the potential recipient of government subsidies, so we cannot rule out that this is about wishful thinking. One of the sectors where we reportedly threatened is the reduction of energy demands.
Building of large logistics and industrial buildings started in the Czech Republic in the midnineties; its construction boom peaked in 2000–2009. The industrial buildings are built even now, at the time of significant recession in building industry. Some flat roofs of this type of buildings show many defects and need extensive repairs and overall reconstructions. The findings and experiences of these repairs show that it is often about system defects which will in time result in necessary repairs or general replacements of many roofs of the industrial buildings.
During the reconstruction works of residential houses the associations of housing unit owners have to make decisions according to their financial means. It often arises a situation when windows are changed and facades of residential floors are insulated by a thermal insulation. Skirting part of the building and the roof is often in seclusion interests. Subsequent roof insulation therefore brings a number of design and implementation issues. This paper describes the necessary structural modifications of the existing double-deck roof structure (i. e. cold deck roof) to single-deck flat roof (i. e. warm deck roof) and increased financial costs caused by successive structural modifications made without consideration of the follow-up.
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.
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.
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.
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.
New Civil Code enacts special type of solidary obligation to remedy the defects of building constructed under contract for works. All subcontractors (suppliers) of constructor, investor`s technical supervisors or construction project designer are solidary responsible together with the constructor in case the defect can be attributed to the performance they provided. However, these parties need not to be the parties to the contract for works itself (and usually are not) as their obligation arises by law.
The remedies that the investor can claim on these co-debtors, however, are limited to right to demand the repair of the defect. Investor may demand remedy on any of the co-debtors and all the co-debtors are obliged to perform the remedy in full.
The investor has to give notice to the debtor within a reasonable time. The notice can be sent to any of the co-debtors but we advise all investors to give notice always to the constructor first or together with the other co-debtors.
It is presently in construction increasingly seen a return to natural materials. This trend is closely related with the ever increasing demands for improving the energy performance of buildings and also the reduction of environmental burden on the industry to the environment. During application of natural insulation materials, however, still face with two main disadvantages of these materials. It is their moisture sensitivity associated with a porous material structure, and then an adverse reaction to fire. The paper is devoted to the study of the moisture behavior of fibrous thermal insulation materials, fiber-based modified chemical additives in order to improve their moisture sensitivity.
Moisture in most of buildings can be limited by different methods. Problems are divided into two papers. The author analyses the conditions of moisture-spread in building in the first part of paper and he solves the selection of sanitation method with less frequent technology of realization. The specific cause with utilization of air insulation system is presented in this part.
The article deals with a new product in the Czech market that is quickly getting to awareness of potential clients and gaining a significant place in the local real-estate market. Until recently, the inspection of immovable properties was an unknown concept. Nevertheless, in recent two years such assistance service is being more and more popular. Pertinent specialised inspection companies assist the real property buyer in eliminating potential risks that are related to selection and purchase of a given building. A competent certified inspector checks up to about 200 items of the building and compiles an expert report to help the client to correctly decide whether he should buy the given building or not. The inspector will acquaint the client with a real purchase price, precisely describe all the defects and how to correct them, and finally, he will hand over to the client a complete budget to cover the cost of necessary repairs.
In 2013 the inspection of real properties comes to one of the fastest growing segments of Czech economy. The people intending to buy any real property are more cautious and, now at the time of an economic uncertainty, they begin using the above relatively new assistance service in a large extent.
Moisture in moist buildings can be limited by the most different methods. Problems are divided into two papers. The author of paper analyses the conditions of moisture-spread in building in the first part of paper and he solves the selection of sanitation method with less frequent technology of realization. The concrete cause with utilization of air – insulation system then will present in the second part.
The purpose of this paper is to inform about research and development results of special composite materials with enhanced capacity to accumulate infrared radiation. The aim of this project was to create an adjustment for wall and ceiling surfaces enabling good conduction, absorption and storage of thermal radiation with subsequent slow release of heat energy stored during periods of intermittently heating. This proposed solution in conjunction with infrared heaters and air conditioning equipment provides sufficient thermal comfort in heated spaces during winter season and thermal stability of rooms in summer. The main emphasis was on cost saving and increased efficiency of heating systems and cooling units.
The article presents one possible solution and principle for increasing absorption of infrared radiation and accumulative ability. The emissivity and surface temperatures of the developed sample were measured within the frame of the experimental works on real laboratory models in cooperation with specialists from Brno University of Techology (BUT) in Faculty of Mechanical Engineering (FME) and Faculty of Civil Engineering (FCI). The analysis of thermal comfort and energy balances including the assessment of the suitability in summer and winter was performed as well.
Thin-walled composites made of fine-grained cement-sand matrix reinforced by alkali-resistant glass fibres are currently used for the range of applications in the building industry, especially as architectural elements and cladding panels. Their advantage is mainly low weight as well as resistance to mechanical and weather impacts. These preconditions led to an innovative solution of cladding elements for accumulation and consecutive utilization of solar energy. Solar energy is transformed into heat energy by the means of an integrated pipe system and the heat achieved is deposited by the means of a heat water reservoir. Element surface can be set with photovoltaic cells. This material is possible to use as a roof panel as well. On the contrary to standard robust photovoltaic panels a difficult superstructure is not necessary and roof structure assembling is much easier. A wide range of simulation trials in interior as well as real tests in exterior was carried out with cooperation of a renowned company from the photovoltaic branch.
The weakest part of concrete high-rise block are their envelopes, so most of regenerations are dealing with reconstruction of existing envelopes. It related of the replacement of window openings, the installation of additional contact thermal insulation or modifications of projecting structures, including loggia glazing and, last but not least, changes in the colour shading of the surface façade layer. These adjustments can improve energy efficiency of the building, but secondary negative effects on the interior environment in terms of the daylight level must also be considered. In this study we tried to take account of both width and shape of jamb of the window with taking into account the effect daylight inside the room.
Measurement of short term water absorption and thermal conductivity was carried out on samples of traditional insulation and the insulation samples from natural fibers. Further, the measured change in thermal conductivity after soaking and subsequent drying of the original weight.
The results showed that the thermal insulation of natural materials retain their original properties – thermal conductivity, shape, compared to conventional insulation.
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