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 Replaces repealed conflicting CSN 73 0821.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.
Archiv článků od 12.10.2009 do 2.8.2010
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.
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.
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.
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.
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.
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.
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.
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.
This article extends the article "Ventilation with heat recovery in flat - yes or no?" and it is concerning with pressure forced ventilation with electric heating coil. This unit includes ventilator, which sucks the external air in from the façade. The electric heating coil with the power of 250 W preheats the external air which is distributed to the rooms with the air distribution system. Nowadays there are a lot of these units on the market that differ in air volume and heating power. The aim of this article is to investigate whether this unit ensures good air quality and what are the costs. The paper was made within the framework of the R&D project performed by the experts in the company EkoWATT, Czech Republic. R&D project VAV-SP-3g5-221-07 is supported by the Ministry of Environment.
The basis of any sort of traditional analysis of wooden objects is a visual survey, which is among the simplest and oldest non destructive methods used in technical construction surveys. Allows to detect biotic surfaces as well as any visible mechanical damage of the wood. Of course, a problem occurs when it is necessary to accurately define the total damage to the individual elements of the construction, in other words, identify the extent of the internal damage, locate the limit between the healthy and already damaged parts, eventually, determine the mechanical and physical properties that designers require as a basis for projecting the remediation measures.
Nowadays the ventilation and indoor air quality is a main issue because the quality of the interior environment is in focus of occupants. The main reason of interests is that the new windows are leak tight and natural infiltration is low as well as IAQ. Without the ventilation system the CO2 concentration is above the healthy standard (1200ppm). To achieve this CO2 level demands a lot of energy and to supply low temperature from outside directly cases also unsatisfactory thermal comfort. The ventilation with heat recovery is one of the possible solutions for energy savings. In article the deep economyy&energy calculation was performed by using building performance simulation tool IES<VE> and suggestion for manufacture was given. The paper was made within the framework of the R&D project performed by the experts in the company EkoWATT, Czech Republic. R&D project VAV-SP-3g5-221-07 is supported by the Ministry of Environment.
The article is dealing with a quality of living on the block of flats and it reveals innovative approaches of the retrofits. It tries to serve inspiration and solutions of sustainable potential of such building retrofits from the architectural point of view. Find attached case study of architectural solutions of complex block of flats retrofit. The three presented approaches represent various ways of possible solutions.
The ČSN EN ISO 13370 Thermal performance of Buildings – Heat Transfer via the ground – Calculation methods has been valid since 2000. Until 2008 it was concurrent with the ČSN 06 0210, which was used to floor structures on soil. After its repelling, the above mentioned ISO standards became the only applicable basis for the design and evaluation of floor constructions and the conclusions arising from their use are not yet sufficiently known among the scientific community. The use of these ISO standards introduces entirely new principles of design, which are vastly different from those that have been used for several decades. The article illustratively solves the problem of the calculation of the heat transfer coefficient from floor structures built on the ground, focusing mainly on surface (indoor) objects.
The author draws attention to the deterioration of the quality of indoor environments in flats where the original windows have been replaced by modern, tight windows, which although improve the flat's energy balance, they also limit the possibilities for ventilation. Moisture that has not been ventilated accumulates in the flat, which leads to mould growth, and in the case of gas appliances, there are also exhaust gases, which are are toxic substances that lead the health problems, intoxications and even death. In the Czech legislation there aren't sufficient basis for an unambiguous determination of the requirements for the quality of the indoor environment of flats, including the requirements for their security, i.e. ventilation. The information can be found in selected European Standards, the author cites ČSN EN 15251.
We can observe in the Czech press a significantly higher frequency of expressions suchs as passive house or energy-efficient construction, specially in connection with the subsidy program “Zelená Úsporám”. However, the reality is that the number of passive houses built is very low, moreover, in some of the so called passive houses there can certainly be doubts about their actual properties.
The article deals with the possibilities of generation of fires based on analysis carried out after liquidation, whether indoors or outdoors. These are primarily signs on wood, metal and glass, but also to eliminate false indicators of fire. These factors may help in investigating the source of the fire, how it spread, or its duration. This assessment is impossible without years of experience, acumen and knowledge of how materials behave when on fire.
In the first half of this year new came in force new standards that define new requirements for the design of thermo insulation systems in buildings. They are ČSN 73 0810 - Fire safety of buildings - Common provisions (April 2009) and ČSN 73 0802 - Fire safety of buildings- Non industrial buildings. The changes in these standards bring a number of major innovations. Let's have a look with them with the aid of images.From the result it is evident that the implementation of external thermal insulation systems for buildings with final approval before 200, and new buildings must follow the additional requirements listed in the articles of the standards ČSN 73 0810 and ČSN 73 0802, particularly in relation to the classification of types of components on the DP1, DP2, DP3. The implementation of additional insulation requires good design, preferably done by a specialist, the application of comprehensive quality and the choice of contractors with certifiable good references.
The application potential for solar energy use in buildings lies in supply of thermal and electric energy and natural daylighting. To use incident solar energy from building envelope effectively, multi-functional construction elements combining several purposes should be introduced as a standard part of building construction. Examples of such concepts are presented: hybrid air/liquid collectors for heating and ventilation purposes, hybrid photovoltaic-thermal (PV/T) collectors for combined thermal and electric energy supply (glazed, unglazed, air/water cooled), linear Fresnell lenses collectors for removal of heat load from direct component of solar irradiation to thermal storage and allowing the natural diffuse daylighting.
zpět na aktuální články