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Archiv článků od 19.4.2010 do 9.8.2010

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9.8.2010
Ing. Jiří Frankl, PhD, Ústav teoretické a aplikované mechaniky, v.v.i., Akademie věd České republiky

From a large group of wood-damaging fungi, only a few species participate on degradation of wood built in various building constructions. In spite of that, these species often cause significant damage by their activity. The contribution summarizes knowledge gained during surveys of various wooden constructions of buildings in the last ten years. It describes vulnerable places of constructions with frequent occurrence of wood-damaging fungi, usual extent of damage, causes of creation and development of infestation by wood-damaging fungi and the most common directions of their further spreading. The contribution contains also statistical analysis of generic structure of wood-damaging fungi in particular vulnerable places.

9.8.2010
Ing. Vladimír Galád

Sophisticated heating solutions lead to the fact that if at any given stage of the thermal insulation a TRV is properly fit and adjusted and, at the same time, a sophisticated substation solution is installed, one that will “know” how to prepare and maintain the required parameters, mainly during the heating season, then there will be nothing to renovate or solve during the lifespan of the heating station, other than adjusting the temperature and hydraulic parameters correctly.

2.8.2010
Ing. Roman Zoufal, CSc., PAVUS, a.s.

Prepared text by experts from scientific, research and teaching and is designed for planners and government workers in the resort fire safety. Value measurements indicates a conservative estimate of fire resistance by concrete, steel, steel-concrete, wood and masonry structures of the relatives simple calculations metod. In compliance with the text set and boundary conditions allows safe setting fire resistance. Replaces repealed conflicting CSN 73 0821. The values are based on the determination of fire resistance according to European design standards, the conditions of the Act and regulations on fire prevention and CSN 73 0810: 2009, and the value of the manuals are fully acceptable in the project documentation for construction management. The Eurocodes standards providing calculation methods to determine the efforts applied to each elements which play a structural role in structures submitted to given actions and to check if the mechanical strength of each element is sufficient to resist to this effort.

2.8.2010
Ing. Richard Kuk, PUDIS a.s.

Drainage systems need to be addressed in the first architectural considerations. Many interesting solutions can deal with rain water, but must be prepared in the first proposals for the building and its surroundings. Green roofs, edit terrain, infiltration areas, the building's location in the terrain, etc. may be difficult to solve additionally.

26.7.2010
Ing. Pavel Hejduk, Ing. Anna Kuklíková, Ph.D.

Wood as a building material has the disadvantage of being combustible. Consequently wood structures are seen by many as creating an environment less safe than structures built of noncombustible materials such as steel and masonry. In terms structural mechanics construction must be designed and constructed maintain with load bearing function during the fire load.Text offers an assessment of new and existing structures construction in terms of their resilience in emergency situations. Let´s describe the various tests fire resistance of wood building in detail.

26.7.2010
doc. Ing. Vladimír Jelínek, CSc.

The following contributions, which deal with this problematic, consider the impact of high heat resistance of the walling on the thermal comfort and the design of heating ventilations systems, which are still perceived, as it is the case in buildings with classical walling, therefore, to have lower thermal resistance. For instructions to formulate the effect of walling on the thermal comfort and technical equipment, a general comparison of both the following cases is made, which is simply called building with high thermal resistance of external walls for a low-energy house, and a building with classical walling parameters (e.g. housing estate from the past) as a standard house. The articles are not of exact technical nature and deal with regularly updated dependencies and sometimes refer to previously applicable legal provisions.

12.7.2010
Ing. Petr Bohuslávek, redakce

The standards ČSN 73 1901 Designing of roofs – basic provisions, ČSN P 73 0600 Waterproofing of buildings – Basic Provisions and ČSN P 73 0606 Waterproofing of buildings – Continuous sheet waterproofing – Basic Provisions have been revised in 2010. What kind of new requirements do these new standards bring? How will their approach change compared to previous regulations? We asked the people behind them about this. The current standards for roof designing have been applied since 1999. According to the proposers of the revision, the many implementations of roofs that have taken place since then have been the source of many new findings, which will be now generalised and reflected in the new standards by clarifying certain provisions or establishing new ones. Developments in European and Czech legislations and standardisations are also necessary to be taken into account.

12.7.2010
Ing. Vladimír Sochor, SEVEn, The Energy Efficiency Center, z.ú.

Examples of projects in Energy Performance Contracting
First two projects by the Energy Performance Contracting were prepared in the Czech Republic in 1993. From that time about 200 projects were implemented. The investment for the projects footed up to the total amount about 3 billion CZK. The highest number of the projects was implemented in school buildings with investment from one till ten million CZK. A lot of projects were implemented in buildings of healthcare service. On examples of implemented projects are described main features of the EPC projects for hospitals (the biggest project with investment over 100 million CZK), for schools (mostly smaller projects) or for more buildings in one public tender (municipalities or regions).

The EPC and its relations with other activities in connections with energy savings
In 2006 the Directive 2006/32/EC on energy end-use efficiency and energy services was adopted for the support of international activities on development of energy services. The obligation of each EU member state is prepare and submit to the Commission the Energy Efficiency Action Plan in roughly three years cycles. In relation to the Directive other activities were supported by EC under the Intelligent Energy Europe Programme, as projects: the Concerted Action on the ESD, ChangeBest, EESI or Pernament. Internal Czech initiative is under activities of Czech ESCOs, which are preparing Association of energy services companies.

5.7.2010
doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha

The attenuation of sound wave with bends is mostly used in the design of noise walls, curtains and barriers along ways with intensive traffic (roads, rail and tram). Noise reduction from stationary sources with curtains is less common because it is always better to place the noisy device in the machine hall. This is then ventilated through a system with big enough dimensions so as to absorb sound, which then blocks the source of sound and the fan noise. Let's look at some specific installations seen in this context as well as calculations of the sound attenuation bend.

14.6.2010
Ing. arch. Miloš Solař, Národní památkový ústav

The problematic of energy savings should not be limited only to thermal insulation and occasional use of alternative energy sources. The energy used not only for heating, but also for ventilation and air conditioning. Significantly affect the consumption requirements, deciding which areas will be heated and at what temperatures. Energy is needed to produce construction materials, their transportation and eventual waste handling. The lifespan of the proposed construction and the complexity of its liquidation should be one of the essential criteria when deciding on contemplated modifications. It is necessary to consider buildings as architectural heritage.

7.6.2010
doc. Ing. Jaroslav Solař, Ph.D., VŠB TU Ostrava

The article deals with the issue of unwanted condensation of water vapour on internal surface of building structures. Building and physical conditions of surface condensation of water vapour is analysed. It discusses possibilities of technical solutions leading to elimination of the mentioned negative phenomenon – change of use, adjustment of peripheral structures, reaching the required parameters of internal air by natural ventilation or through air-conditioning.

26.5.2010
Vlastimil Růžička, redakce

The Czech Council for Green Buildings and the British Council, in addition to their other activities, are organising the so-called Biohouse seminars, which include visits to selected buildings. We have attended one of them and we had a look at three interesting buildings in the surroundings of Prague. The first stop of the mini-bus was Pikovice, where an untraditional low energy wooden house, with a gazebo is located. We were expected by the investor, the architect and the projector. The second building, which had almost passive standards, we shown to us by the investor, who personally devised to ideological concept of the house in the outskirts of the village Tehov u Říčan. The third building, located in the garden of the former parish house in Sluštice u Prahy, was shown to us by a representative of the investor, who took us to the world of children. It is a beautiful wooden building projected as a pre-school in a Waldorf style.

17.5.2010
Ing. arch. Miloš Solař, Národní památkový ústav

What should be respected during renovation works on roofs so as to maintain the architectural quality of the original design? Solar collectors and photovoltaic cells constitute a disruptive element in historical buildings and buildings in historical areas. Among others, the reasons are legal, because the law provides equal access to buildings with a same degree of legal protection. Exceptions can be considered in situations without an indicated conflict. For example, on garage roofs in courtyards or roofs in buildings erected after the WWII. And even in these cases, the installation of panels should be appropriately considered. Of course, even new architectural and artistic works as well as other specific situations will require an individual approach. However, in terms of frequency we are talking about exceptions that confirm the general view of the preservations institutions, that the placement of photovoltaic systems in areas of cultural or historical heritage is not desirable. Let's have a more detailed look at this problematic.

17.5.2010
doc. Ing. arch. Hana Urbášková, Ph.D.

Windows have always been considered a construction surface that had to allow in enough day light and at the same time, protect the interior from wind and rain. Windows protected the house from the outside world, while at the same time enabling communication. The technical capabilities, along with the climatic and economic conditions of different historical periods shaped the appearance of the windows, which also helped create the different architectural styles. The proportions, materials and the segmentation of windows on the façades were also influenced by geographical location, cultural influences and regional aesthetics. The height and width relationships in windows, and their relationship with the total area of the walls, the appropriate width of the interior posts and other similar parameters where basics of the compositional works. Much attention was paid to the fine details. Window openings were framed with various decorative ornaments. The windows of a passive house are among the most complicated structures of the building.

10.5.2010
Vlastimil Růžička, Ing. Petr Bohuslávek

One of the tools for the implementation of a national housing policy is the State Housing Development Fund. Its director, Dr. Jan Wagner, has given TZB-Info an exclusive interview where he speaks about the Czech Housing fund, the possibilities to combine subsidies and the difficulties for investors and developers.

2.5.2010
Ing. Petr Živný, Pro Windows, s.r.o.

Do you know how to choose a supplier and installers for windows? The article answers to important questions regarding the choice of windows, their frames, glazing, ironwork, sills and accessories such as shadings, etc. The author speaks from personal experiences with suppliers, manufacturers and technical supervisors. The article wants to help people buy windows with the best price/quality ration and ensure their long term satisfaction.

26.4.2010
prof. Ing. Jiří Vaverka. DrSc., VUT v Brně, Fakulta stavební

The basic importance of the use of inert gas in the space between insulating glasses is its lower thermal conductivity, i.e. the ability to provide greater resistance to heat transfer. Simply put, the inert gasses (argon, krypton, xenon) have this property because in principle their molecules do not create in structure among themselves or with particles from other gasses and strictly occur in monomolecular arrangements, which significantly reduces the transfer of kinetic energy between the molecules, which is the driving force of heat. The paper analyses the variabilities of the heat transfer coefficient of Ug glasses depending on changes in the concentration of inert gases and the width of the space between insulating glasses.

19.4.2010
Ing. Vladimír Sochor, SEVEn, The Energy Efficiency Center, z.ú.

Advantages of the EPC methodology in comparison to other solutions

EPC methodology has a lot of advantages in comparison to other solutions on reconstruction of energy systems. The most important feature is assumption of risks, which customer would have to solve. The most important adoptable risk is guarantee for the savings. Unique feature of the EPC is the same motivation for the ESCO and for the customer, both to invest money by the most effective way (efficient quality equipment) and to reach as high savings as possible. It is very appealing that the ESCO is able to assure financing of the project. The customer needs not spend the investment during implementation of the energy efficient measures and he pays it back during the investment during the contract duration from saved operational costs.

Specific features of the EPC in the Czech Republic

The Energy Performance Contracting was introduced in the Czech Republic in 1992. From that time the EPC methodology was developed enough in the field of documentation for public tendering process and also in the field of text of contracts for the energy services provision. Unfortunately the state support of EPC project development is in the Czech Republic very weak. Nevertheless the situation is from ESCOs effort and interest of customers very good. By number of the EPC projects and size of the projects is the Czech Republic in Europe on the top position, including Germany, France, UK, Austria and Sweden.

19.4.2010
Roman Jirák, DECOEN znalecký ústav s.r.o., ČVUT Praha

Windows, as fillings of peripheral orifices in the structure of buildings, are a construction product, which either must be tested or verified for their compliance with the various Czech regulations and standards. One of the most important criteria that window structures must meet is the one prescribed by ČSN 730540-2 Thermal Protection of Buildings from April 2007 The compliance of the inner surface temperature factor with the standard ČSN 730540-2 must be verified separately for each orifice filling structure. So far, there are no universally applicable rules that determine which edge of glazing units can be applied to with structure. The area of the glazing joints is among the riskiest parts of the whole structure, and that is why two basic design rules were derived in order to provide an increase the internal surface temperature in that area.

19.4.2010
Martin Sedlák, Aliance pro energetickou soběstačnost

More than 15 years TZB-info is focused to perspective equipment for building services with priority in heating. During this period the main question: "how to heat" shifted to question: "how to reduce heat loses". For example France is planning for new buildings only passive standard, and begining 2050 only so-called quasi-zero buildings. In Czech Republic one of significant impulses is subsidy program Zelená úsporám (Green for savings). Technical solutions are widely known in professional community, unfortunately high investment cost and long payback time are the main barriers for broader expansion of the solutions. Folowing article is the first from a serie focused to long time planing of reduction of energy consumption in the Czech Republic. From two ways - to prospect new energy sources or to reduce energy consumption - the second needs no to destroy another villages or towns.
How can heating for Czech homes be assured while at the same time get rid of the dependence on dirty coal and Russian gas? This is answered by the scholarly study by the DUHA movement – Clean Heating. The solution is based on a combination of investments on home insulation, solar collectors and biomass heating plants. Very important are the new standards for developers and provisional supply of coal from the Bílina mine. The calculations are based on those from the Pačes Commission. There are many opportunities. Increasing the energy efficiency of builings – i.e. insultaions – and the heating potential from renewable sources represent more than 300 million gigajoule. This surpasses the total current heating consumption of Czech homes. The possibilities of insulating Czech homes are also five and a half times higher than the controversial expansion of the coal mines around Most, which is linked with a further devastation of the North Bohemian landscape and the demolition of towns.


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