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TZB-info - Gateway to the world of specialized information

TZB-info is an Internet resource specialising in information on construction, energy savings, and the related fields collectively referred to as mechanical and electrical systems usually known as building services (in Czech abbreviated as TZB). Its primary focus lies within the construction of buildings and energy issues related thereto. Whether you're looking for heating, electricity, heat loss reduction or building efficiency, the portal offers up-to-date information on the developments in those fields every day. The information presented by TZB-info is carefully selected and edited, serving a diverse audience of professionals ranging from designers to installers but also the general public. TZB-info records 750,000 visits every month. read whole text

Latest reviewed editorial research papers in the field of building services engineering

Heating

Zkušenosti z provozu tepelných čerpadel 16: Proč dělat pravidelné servisy

23.12.2024 | Ing. Petr Michal, IVT Tepelná čerpadla s.r.o.
Heating

Limity tepelného komfortu

10.12.2024 | Ing. Zuzana Veverková, Ph.D., ČVUT v Praze, Fakulta stavební, Katedra technických zařízení budov
Heating

Zkušenosti z provozu tepelných čerpadel 15: A zase ty tlaky chladiva!

9.12.2024 | Ing. Petr Michal, IVT Tepelná čerpadla s.r.o.
Ventilating and Air-Conditioning

Practical experience in cleaning ventilation systems in family houses

12.11.2024 | Ing. Pavla Skalická, Luftuj s.r.o., časopis VVI, 2/2024 | Vytápění větrání instalace, 2/2024
Practical experience with the cleanability of parts of the forced ventilation system with heat recovery in family houses. The need for cleaning and design and assembly deficiencies that lead to difficult maintenance. Some policies to make service easier.
Water and Drainage

Možná rizika spojená s produkcí opětovně využitelné vody

8.12.2024 | Ing. Jan Vespalec, Mgr. Martina Repková, Ph.D., doc. Mgr. Michaela Vašinová Galiová, Ph.D.
Water and Drainage

Využití šedé vody v objektech pro bydlení a ubytování

20.11.2024 | Ing. Ilona Koubková, Ph.D., ČVUT v Praze, Fakulta stavební, katedra technických zařízení budov
Trubicové solární kolektory, foto © TZB-infoRenewable Energy

Example of the Design of Thermal Collectors for the Domestic Hot Water Preparation in a Family House

11.12.2024 | Ing. Lukáš Skalík, PhD., EUR ING, Stavebná fakulta STU Bratislava
It is possible to design solar energy systems (SES) with solar collectors in several ways: manually - by calculation; using software - there are several calculation programs for SES design, e.g. T*Sol from the renowned German company Valentin software for the calculation of thermal heat collectors, or PV*Sol for the design and simulation of photovoltaic power plants of any size; or according to the manufacturer's instructions - if we know the manufacturer/supplier of the equipment when designing the SES, we can use the recommended calculation procedures from the design documents of the given company, provided that they are available.
Foto © ELyrae, Fotolia.comRenewable Energy

Fotovoltaické elektrárny: Globální instalace a růst v roce 2023

25.7.2024 | prof. Ing. Vítězslav Benda, CSc., ČVUT v Praze, Fakulta elektrotechnická, Katedra elektrotechnologie
Photovoltaics is becoming the fastest growing segment of energy production in the world.
The article introduces the current state of photovoltaics in the world. It indicates the current installed capacity of photovoltaic systems (total cumulative and annually installed power) and the share of individual countries in the installed cumulative and annually installed power. It also deals with the share of photovoltaics in electricity production in selected countries and compares this share with the global average and the EU average. It also deals with changes in photovoltaic module technologies, change trends and prices of photovoltaic modules and provides information on the development of the annual production capacity of the largest manufacturers of photovoltaic modules.
Electrical Engineering

Metody pro 3D skenování historických hliněných staveb

16.12.2024 | Ing. Jan Müller, Ph.D., Mgr. Martin Novotný, Ph.D.
Foto © luchschenF, Fotolia.comElectrical Engineering

A True Digital Transformation of the Company and a Unified Integrated Operating Environment

2.4.2024 | Ing. Jiří Holoubek, prezident Elektrotechnická asociace České republiky
IT systems in companies are often incompatible and their data communication is very complicated. A unified, integrated operating environment ensures real online communication not only of technological devices, but also technology for quality monitoring, systems for order planning, service and maintenance, as well as energy management.
Electrical Engineering

Fiber-optic FBG Sensors

25.1.2021 | Ing. Radim Šifta, Ph.D., NETWORK GROUP, s.r.o.
The paper describes special types of fiber optic point sensors based on FBG (Fiber Bragg Grating) and FP (Fabry-Perót) structures. First part of the paper deals with principle of FBG and FP and their exposition. Next part is focused on different types of FBG and FP sensors and principle of interrogation units. Finally practical examples of use are listed.
Electrical Engineering

Fiber Optic Sensors

20.1.2021 | Ing. Radim Šifta, Ph.D., NETWORK GROUP, s.r.o.
The paper deals with special types of sensors that use optical fibers to measure various non-electrical quantities. The introduction describes the principle of light transmission in optical fibers and their applications. Main part is focused on fiber-optic sensors and their dividing. Special attention is paid to the distribution sensory systems and their practical application.
Elevators

Provozní prohlídky výtahů

24.8.2015 | Ing. Bohuslav Kratěna, Unie výtahového průmyslu České republiky
Elevators

Poznatky z prověřování (auditu) firem provádějících servis na výtazích

20.7.2015 | Vladimír Hulena, pověřený HK ČR k provádění auditu
CSN 27 4002 2014 Safety rules for lifts - Operation and service of lifts has introduced a new term by an authorized service company. It is the transparency of professional competence companies in servicing elevators, to owners / operators can better decide with whom an agreement that service because it has a major impact on their responsibility to ensure the safe operation of elevators. Therefore, for this situation was the subject of speculation, it was decided to examine service firms independent commissioners, contracted authorizing body, in this case, the Chamber of Commerce, which, when positive evaluation subsequently issue a certificate of authorization, and the company name may Authorized service company use.
VýtahElevators

News in the standards and audits for elevator industry

28.7.2014 | Ing. Jan Dvořák, Ing. Bohuslav Kratěna, Vladimír Hulena
Union for Elevator Industry summarizes the most important news in the standards and audits, as presented at the seminar Elevators 2014. This includes controversy with a new concept of authorized service company that has been published on our portal in advance.
Zákaz používání výtahu za požáru - výtah neslouží k evakuaci osobElevators

Standards in the projects in terms of fire safety of elevators

21.7.2014 | plk. Ing. Zdeněk Hošek, Ph.D., Ministerstvo vnitra - generální ředitelství Hasičského záchranného sboru ČR
Elevators belong to a very important building services and technologies. For these reasons, they need to pay attention not only in terms of proper technical implementation, but also in terms of fire safety. In particular, fire and evacuation lifts, which are also very important fire safety devices must also meet the stringent technical requirements of fire protection.
Energetics

Analysis of the Current State of Construction and Demolition Waste Management and Possibilities for Further Development of Its Use

29.7.2024 | doc. Ing. Miroslav Škopán, CSc., VUT v Brně, asociace ARSM
The paper deals with the analysis of mineral construction and demolition waste management in the Czech Republic between 2007 and 2022. The analysis is based on data from the Czech Environmental Information Agency. It has been shown that the production of recycled mineral construction and demolition waste has quadrupled in this period and that the share of recycled mineral construction waste in the market of mineral materials for the construction industry is around 15%.
Energetics

Metodika pro obce zaměřená na zvyšování třídění odpadů

26.4.2024 | doc. Ing. Mgr. Jana Soukopová, Ph.D., Ing. Dominika Tóthová, Ph.D.
Facility management

Inspection of Steel Structures According to Current Legal Regulations and Standards

17.12.2024 | Vladimír Baletka, jednatel společnosti eFACILITY consulting s.r.o.
The article focuses on the importance of regular inspections and maintenance of smaller steel structures, such as roof walkways, fire escape stairs, or railings, from the perspective of applicable legal regulations and technical standards. It highlights the key requirements of ČSN 73 2604 and other legislative measures that ensure the safety and long-term reliability of these structures. The text also provides practical advice on inspection procedures, inspection frequency, and inspector qualifications. This article serves as a valuable guide for property owners and professionals in occupational health and safety (OHS) and facility management.
Facility management

Obligation to Install Charging Stations for Electric Vehicles under the New Building Act

12.11.2024 | Vladimír Baletka, jednatel společnosti eFACILITY consulting s.r.o.

RECENT REVIEWED EDITORIAL RESEARCH PAPERS IN THE FIELD OF BUILDING SERVICES ENGINEERING


Heating | Ventilating and Air-Conditioning | Water and Drainage | Renewable Energy | Electrical Engineering | Energetics

Latest reviewed editorial research papers in the field of construction

Shell Construction

The Path to Sustainability: Reusing Parts from Dismantled Timber Building

17.12.2024 | Ing. Jakub Diviš, Ph.D., Ing. Martin Hataj, Ph.D., Ing. Pavla Novotná, Kamila Novotná, MBA, Ing. Jan Pešta, Ph.D.
The building industry produces more than 30% of the European Union's waste. To reduce this waste, buildings should be designed in line with the principles of the circular economy, so that the products and materials they contain can be removed and reused at the end of the building's life cycle. Therefore, a modular system has been designed, the load-bearing part of which is made up of prefabricated frames composed of plywood. To verify the actual reuse potential of the structure, an experiment was carried out in which a house was assembled and operated for one year. After dismantling the house, the reuse potential of each element was assessed. In this paper, the potential of the main elements of the system for reuse, which overall amounts to 98% by weight of materials used in the system, is described, together with the key barriers to material recovery of the dismantled elements.
Shell Construction

Poruchy dřevěných prvků krovových a stropních konstrukcí a jejich údržba

15.12.2024 | Ing. Andrea Nasswettrová, Ph.D., MBA, ProDřevo ateliér, Společnost pro technologie ochrany památek STOP, z.s.
Ocelová konstrukce © Fotolia.comShell Construction

Možnosti zabezpečenia požiarnej odolnosti ocel'ového nosníka

2.12.2024 | doc. Ing. Magdaléna Štujberová, PhD., Stavebna fakulta STU v Bratislave, Katedra kovových a dřevených konštrukcií
beton © Fotolia.comShell Construction

Využitie odpadov pre zvýšenie trvanlivosti cementových kompozitov

25.11.2024 | prof. RNDr. Adriana Eštoková, PhD., Ing. Miriama Čambál Hološová, Ing. Martin Jaš, prof. Ing. Alena Sičáková, PhD.
Insulation, Roofs, Facades

Roof with Transparent Elements

16.10.2024 | doc. Ing. ad Ing. arch. Milan Palko, PhD., Ing. Adela Palková, PhD., Ing. Silvia Križanová
The transparent roof and its position predestined it to the position of the primary element from the point of view of the potential of using solar radiation. Climate change brings an increase in outside temperature and the number of sunny days, which can lead to unwanted overheating of buildings. Preservation of optical properties and elimination of thermal gains can be solved by a dynamic glass system. Thermochromic glass systems have a high potential for transparent roof coverings and through gradual development can be an optimal solution for autonomous regulation and limitation of overheating in the summer.
Insulation, Roofs, Facades

Recycled Plastics in Construction, their Applications and Composites Usable in Construction Practice

2.9.2024 | Ing. Miriam Ledererová, PhD., STU Stavebná fakulta Bratislava
Plastic waste in the construction industry can consist of various plastics such as polyethylene, polypropylene, PVC, ABS, polystyrene, polycarbonate. Plastic waste in construction can come from packaging, insulation and other materials. Plastic waste not generated in the construction industry is also recoverable. The best way is to recycle plastic waste into materials that can be used for building materials, fillings, structures, etc. They can also be used in the production of lightweight concrete.
Insulation, Roofs, Facades

Návrh ploché dřevěné střechy dle pravidel CSS

1.9.2024 | Bc. Karol Plaštiak, Cech strechárov Slovensko
In the architecture of the 20th century, as well as in contemporary modern architecture, we can observe the high popularity of flat roof constructions in massive constructions of masonry and monolithic structures. It is therefore logical that there are many practical rules for this type of flat roof construction. There are not so many technical rules and recommendations for flat roof structures made of wood and in wooden buildings in Czech and Slovak countries due to the loss of traditions for this material and details during the socialist period. Therefore, the need for low prices has in the recent past enabled the realisation of flat roof projects made of wood and in wooden buildings, which, due to both incorrect planning and errors in implementation, have led to damage to the structures. In response to these problems on the market, the Slovak Roofers Association had a technical committee created. The task of the commission is to compile a complement to the CSS rules for the construction of flat roofs made of wood and in wooden buildings. The inspiration is the currently valid STN standards, supplemented by good examples of constructions and details of compositions from the D-A-CH countries, which have a long tradition with wood as a material in constructions.
Windows, Doors

Bonded Joints of Glass Structures

23.12.2024 | Ing. Jakub Mareš, Ing. Yasmina Boutar, Ph.D., prof. Ing. Martina Eliášová, CSc.
This paper presents the results of an experimental investigation into fully transparent bonded joints for load-bearing glass structures. The research specifically focused on the surface properties of glass that affect the load-bearing capacity of the joints, such as surface energy, wettability, and roughness. It also discusses the differences between the tin and air sides of the glass sheets.
The findings are supported by tests conducted at the Faculty of Civil Engineering at CTU between 2021 and 2023. Tensile and dynamic tests of the selected adhesive LOCTITE® EA 9455 as well as shear tests of single-shear glass-to-glass joints, were evaluated, with a focus on the load-bearing capacity of the joints at elevated temperatures.
The paper concludes with a summary of the results and suggests their implications for engineering practice.
Windows, Doors

Principles of Installation and Drawing Opening Fillers - Part 2: Doors

16.9.2024 | Ing. Zuzana Rácová, Ph.D., Ing. Aneta Libecajtová, Ph.D.
The article focused on the issue of installing door panels in interior vertical load-bearing and partition structures. The paper presents selected types of door panels primarily used in apartments and family houses, describes the principles of their installation, and their depiction in drawing documentation in accordance with the ČSN 01 3420 standard for drawing construction parts. It is necessary to correctly and clearly apply the rules of the standard to the depiction of currently used door panels.
Windows, Doors

Principy osazování a zakreslování otvorových výplní – Díl 1: Okna

8.4.2024 | Ing. Zuzana Rácová, Ph.D., Ing. Aneta Libecajtová, Ph.D.
The article is focused on the issue of installing windows in external walls and their drawing in accordance with the standard ČSN 01 3420 Construction drawings - Presentation of general arrangement drawings. The paper highlights the obsolescence of previous solutions in light of current requirements for the energy efficiency of buildings and technological advancements in construction. Specifically, it is focused on the principles of installing opening fillings, including thermal and technical requirements, and technological aspects. It is shown that incorporating new technological processes and energy efficiency requirements necessitates reflecting these changes in the project documentation as well. Furthermore, the article addresses the depiction of current solutions in construction practice in accordance with the ČSN 01 3420 standard at scales of 1:50 and 1:20.
Foto ©Ingo Bartussek - Fotolia.comWindows, Doors

Thermal Properties of Double Window and Modern Construcions Jamb

20.3.2023 | Ing. Lucie Kudrnáčová, Ph.D, ČVUT v Praze, Kloknerův ústav, Oddělení stavebních materiálů
The paper deals with the comparison of the thermal properties of jamb for different types of windows. In the case of reconstruction, it is often necessary to preserve the original double- windows or to use modern materials due to the thermal solution of the building. Modern constructions mean the use of double or single windows with thermal-insulating glazing. These changes in the construction of the window have an effect on the thermal processes on the structure. One of the important parameters for the assessment of the building structure is the assessment of the internal surface temperature of the building structure. This article shows the difference in finishes and heat flows to remove different types of windows. The reference window for comparison is the original double history window. The results were found in a model environment in 2D software.
Zlatý certifikát SBToolCZLow Energy Buildings

SBToolCZ. The Latest Online Version of the National Building Sustainability Assessment Methodology

6.2.2023 | Ing. Kateřina Klepačová, Ing. Magdaléna Novotná, Ph.D., Ing. Martin Volf, Ph.D., Ing. Jakub Diviš, Ph.D., Ing. Jan Růžička, Ph.D.
ilustrační foto: Main Point Karlín © TZB-infoLow Energy Buildings

Environmental Certification of Buildings - the Situation in the Czech Republic

30.4.2021 | Ing. Zuzana Mrňová, VUT FAST Brno, Ústav stavební ekonomiky a řízení
A responsible approach to the environment is not only related to corporate ecology, but is also increasingly reflected in the design and construction of buildings, which is closely related to the concept of sustainable construction of buildings. With the development of sustainable construction, the need arose to evaluate buildings and their impact on the environment. For this reason, environmental certifications of buildings have been developed, which assess how a building affects its surroundings during its life cycle.
The aim of this article is to find out which environmental certifications exist in the world and which of them are most often used in the Czech Republic. Finally, the certifications are compared and their main differences are described.
ilustrační obrázek © starush - Fotolia.comLow Energy Buildings

Stavebně-energetické koncepce budov ve společenských souvislostech

8.2.2021 | prof. Ing. Jan Tywoniak, CSc., ČVUT Praha, pracoviště UCEEB | Dřevo&Stavby Profispeciál 2020
Wooden Buildings

Přínos 2. generace Eurokódu 5 pro navrhování dřevostaveb

8.7.2024 | doc. Ing. Petr Kuklík, CSc., Ing. arch. Bc. Anna Gregorová
Wood buildings, i.e. buildings in which wood and wood-based products are the dominant material used, are currently the subject of growing interest among developers and the professional public. This is mainly due to the fact that they offer an alternative way of constructing safe buildings with great environmental benefits. The prerequisites for their greater implementation are then created by new versions of European standards. In this paper some new procedures for their design according to the 2nd generation of Eurocode 5 are presented.
Wooden Buildings

Vývoj konstrukčního řešení prefabrikovaného rámového systému pro dřevostavby

18.12.2023 | Ing. Martin Hataj, Ph.D., Ing. Jan Pošta, Ph.D., Ing. Pavla Novotná
Within the framework of the project "Prefabricated recyclable timber-based frame building system", a new building system is being developed, the main load-bearing elements of which are rigid frames made of timber-based material. The principal investigator of the project is ecokit s.r.o. and the co-principal investigator is UCEEB CTU. This paper presents the development of the load-bearing structure of the frame system.
Wooden Buildings

Ochrana dřeva, trvanlivost povrchové úpravy dřevěných fasád a teras

2.10.2023 | Ing. Petr Ptáček, Ph.D., ČVUT v Praze, pracoviště UCEEB
The protection of wood in wooden buildings does not seem to be very important due to their location in use class 1 or 2 according to ČSN EN 335, but it is particularly suitable for timber elements that are located close to the foundation slab or are difficult to replace. It follows from the majority of recurring defects, for example plumbing failures, leaks through the roof, facade, inappropriate terrain height around the base plate or as a result of a tornado, that it is necessary to protect at least the foundation threshold according to the structure of the wooden building, preferably up to use class 4 according to ČSN EN 335, which is only possible by pressure impregnation.
Stěnový panel se svisle orientovanými OSB deskami při experimentálním testováníWooden Buildings

Analýza vlivu orientace desek opláštění na horizontální únosnost a tuhost stěnových panelů dřevostaveb

10.7.2023 | prof. Ing. Antonín Lokaj, Ph.D., Ing. David Mikolášek, Ph.D., Ing. Pavel Dobeš, Ph.D., Ing. Marek Johanides, Ph.D., Ing. Petr Mynarčík, Ph.D.
The paper deals with the experimental and numerical analysis of the influence of the orientation of large-area sheathing panels of load-bearing wall panels of wooden buildings. The experimental results were then compared with the numerical model in SCIA Engineer and with the analytical calculation.
Building Regeneration

Nejčastější statické problémy historických cihelných objektů

20.10.2024 | Ing. Jan Zima, Rekonstrukce památkových objektů-atelier statiky spol. s r.o.
Building Regeneration

Non-destructive Determination of Building Stone Provenance

26.8.2024 | Mgr. Kateřina Kovářová MBA, Ph.D,, Ing. Eva Matoušková, Ph.D.
In our practice, we often face the question of building stone provenance on historic buildings. However, methods providing relevant answers to this question are mostly of a destructive character requiring sampling. Therefore, our research has focused on the use of reflectance spectrometry, which is a very promising and effective non-destructive method. This paper discusses the basic principles and possibilities of this method with regard to its application to historic buildings and decorative stone.
Building Regeneration

An Example of the Use of Available IT Technologies During the Renovation of the Castle in Nemysl

8.4.2024 | Ing. Denisa Boháčová, Ph.D., prof. Ing. Pavel Kuklík, CSc.
The paper presents the original condition of the castle in Nemyšl near Tábor together with the subsequent process of its rehabilitation. This requires a careful evaluation of its condition, determination of the remediation procedure along with condition monitoring to ensure safety on the construction site. To accomplish this task - the abbreviation SHM (Structural Health Monitoring) is used abroad - the available possibilities of current information technologies have been used.
Building Regeneration

Current Civil Engineering Activities Contributing to the Reliability and Sustainability of Historical Monuments

1.4.2024 | Ing. Denisa Boháčová, Ph.D., prof. Ing. Pavel Kuklík, CSc.
The paper deals with the role of engineers in the contemporary world. In particular, it is focused on presenting the current possibilities in preserving historical monuments and their maintenance. In two case studies, point out the new possibilities offered by computer technology and connecting the involved actors through the web. It also mentions the WEC 2023 World Engineering Convention in a certain way. Due to the scale, the first, general part is presented first, which is supplemented by the concept verification while monitoring the retaining wall of St. James Church in Nepomuk. In the following separate paper, an example of the use of these technologies in the rehabilitation of the castle in Nemyšl is presented in more detail.
Building Physics

Daylighting in a Dwelling Room Lit by a Window with an Area Equal to 10% of the Room Floor Area

21.10.2024 | Ing. et Ing. Lenka Gábrová, Ph.D., Mendelova univerzita, Lesnická a dřevařská fakulta, Ústav nauky o dřevě a dřevařských technologiích
The Prague and Brno Building Regulations approved in 2024 no longer require compliance with daylighting requirements in dwelling rooms in buildings with a closed or semi-closed construction line. In these buildings, it should be sufficient to prove that the window area is at least one tenth of the room floor area. The paper deals with the daylighting evaluation in differently obstructed rooms whose window area is exactly 10% of the room floor area.
Building Physics

Činitel jasu a činitel odrazu světla ve výpočtech denního osvětlení

12.2.2024 | doc. Ing. Jan Kaňka, Ph.D., člen TNK 76 Osvětlení, ČKAIT Praha
When calculating the daylighting of buildings, the properties of shading obstacles are expressed either by means of a brightness factor or by means of a light reflection factor. The article reports on the relationship between these two factors and offers the JAFAS 2024 program to calculate the brightness factor in a simple urban situation.
Zjednodušený princip přenosu zvuku přes dělící trámovou konstrukciBuilding Physics

History and Acoustics of Traditional Timber Joist Floor Structures – 2nd Part

29.1.2024 | Ing. Lubor Kalousek, Ph.D., Ing. Zuzana Fišarová, Ph.D., Ing. Zdeněk Vejpustek, Ph.D.
The article is focused on the issue of traditional timber joist floor structures and floor compositions from the period up to the first half of the 20th century. In building practice, we very often encounter these structures in residential buildings that are the subject of structural changes. During these interventions, the basic ideas of the original technical solution are not always respected and some physical parameters of building are degraded. The article describes the principles that were devoted to these types of structures in historical legislative and standard regulations and further in professional literature. The original historical solutions are presented on a practical example. In relation to building interventions in historic timber joist floor structures, current legislative and standard regulations are described, as well as examples of modern solutions and their limitations.
Princip práce s W-diagramemBuilding Physics

Selected Graphic Methods of Determining the Daylight Factor (Part 2)

15.1.2024 | doc. Ing. Jan Kaňka, Ph.D., Ing. Bc. Jaroslav Vychytil, Ph.D.
The article deals with the description of selected graphic-numerical methods used to determine the amount of daylight. The principle of derivation of these methods is explained and the principle of working with the relevant diagrams is described. Nowadays, we rarely see the use of diagrams in practice, but some professional software uses them either directly or at least in their graphical outputs.

RECENT REVIEWED EDITORIAL RESEARCH PAPERS IN THE FIELD OF CONSTRUCTION


Shell Construction | Insulation, Roofs, Facades | Windows, Doors | Floors, Partition Walls, Surfaces | Low Energy Buildings | Wooden Buildings | Building Regeneration | Building Physics
 
 

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