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.

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.

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.

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.

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.

Author offers practical best practices, leading to significant savings in the preparation of hot water, ensuring the required quantity of hot water, temperature and elimination of microbiological risks.

The article explains the principle of heat recovery and the basic categories of heat recovery units used in HVAC systems. It describes the advantages and disadvantages of individual heat recovery systems and their fitness for purpose.

The aim of the diurnal lightning proposal is to rectify rooms' access to sunlight, which is dispersed in the atmosphere, and to rectify the visual comfort of the users of the interior during daylight hours; i.e. the appropriate lightning conditions for visual work carried out in the interior. The specifications of diurnal lightning are formulated in IEC-730580-1 to 4. These specifications are binding because the relevant articles mentioned in the standards are determined as binding laws and decrees 268/2009 on the technical requirements for construction, 258/2000 on Public Health, 410/2005 on hygiene requirements for educational facilities and the education of children, Government Decree 361/2007 on sanitary conditions at work. In situations where controls of calculations of measurements are not possible or too difficult, it is then necessary to maximise the transparency of computational procedures. In particular, it is necessary to include all the variables that enter into the calculation (factors of brightness shading barriers, factors of transmission and reflection of light). When assessing the accuracy of the calculations, it is also necessary to require detailed descriptions of the computational models used in determining the individual components of the diurnal lightning factors.

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.

On the beginning of the nineties the various technologies of wood buildings, especially of assembled types, developed. Although in the present time wood buildings have already their acknowledged place even in our country in spite of that we can meet their failures predominantly at the elevational planary wooden facings of load-bearing wooden framing. One such case is also south plywood- facade of family house in Middle Bohemia.