Martin Lopušniak

Temperature Stratification of Underfloor and Ceiling Based Air Heating Distribution System in an Experimental Room

Abstract Most of air heating and ventilating systems for passive houses inlet air in floors. It is assumed that a natural motion of air is led upwards, and so the right stratification of temperature in the space is ensured. However, in the case of excellently insulated buildings it is possible to assume that an upper inlet of air is also able to ensure the required layering of temperature. Within the experiment an influence of upper and down air inlet for temperature stratification in the space was followed. Night sensors of indoor air temperature are placed for measurement purposes. Measurements are done in the long term. The results from measurements show that both, vertical and horizontal stratification of temperature in rooms of passive houses are equal regardless of the fact, which system of air inlet is used.

Verification of the thermal insulation properties and determination the optimal position of the reflective thermal insulation layer in the wood based envelope

Abstract To achieve thinner wood based envelope is necessary look for an alternative thermal insulation material, which will have the best possible thermal insulation properties while maintaining affordability. One such material is also reflective thermal insulation layer, but it is necessary to verify the thermal insulation properties and determine the optimal position in the wood based envelope.

Case Study of the Straw Bale House

Straw is renewable material both from the ecological and environmental point of view. It is almost always available at construction sites. Straw is used mainly as filling thermal insulation in structures. This paper deals with design of a two-generation family house. The family house is located in the eastern Slovakia. There is the temperature zone -14 °C. The first goal of this project was to specify the optimal ratio between solid and glazed surfaces in distribution of the specific heat use for space heating. The second goal was to achieve the specific heat use for space heating lower than 15 kWh·m-2·a-1. The specific heat use for space heating has been calculated according to STN EN ISO 13 790 Energy performance of buildings. The project analysed forced ventilation with the heat recovery unit, orientation towards cardinal points, optimal ratio of glazed and solid surfaces of the designed house and their impact on energy performance of buildings. Individual parameters were mutually combined and required goal has been achieved. The specific heat use for space heating was less than 15 kWh·m-2·a-1 in 13 of the evaluated combinations.

Analysis of Energy Sources on Energy Indicators Performance

In the members states of the European Union, portion of buildings in the total consumption of energy represents 40%, and their portion in CO2 emissions fluctuates around 35%. The European Union is trying to protect the environment by reducing energy demand and releasing CO2 emissions into the air. Energy performance is the quantity of energy, which is necessary for heating and domestic hot water production, for cooling and ventilation and for lighting. Based on results of energy performance, individual buildings are classified into energy classes A to G. A global indicator (primary energy) is the decisive factor for final evaluation of the building. The new building must meet minimum requirements for energy performance, i.e. it must be classified to energy class A1 since 2016, and to energy class A0 since 2020. The paper analyses effect of the use of different resources of heat in a family house designed according to requirements valid since 2020, and its subsequent classification into an energy class.

Determination of Fire Resistance of Ceiling Structure Variant Design on the Basis of Timber Using Numerical Calculation Methods

Ability to resist of high temperature impacts during fire is not based exclusively on ignitability of building materials. At the present time, fire resistance is declared mainly through fire tests, but numerical procedures for the determination of fire resistance also represent an effective alternative in this field. Using calculation methods for the determination of ceiling structure fire resistance on the basis of timber is subject of the submitted paper. The main objective of this paper is to demonstrate the fact that timber, or products from it, are building materials capable to resist impacts of fully developed fire for the period of more than 60 minutes in spite of their flammability. Applicability of these results in selected countries of Europe can be seen from the list of requirements.

STN 73 0580 vs. prEN xxxx – A study about the Differences at Daylight Distribution in Attic Spaces

Daylighting design expects significant changes in the near future, although their impacts on the practice and possible orientation are currently under developing. The authors responsible for the elaboration of the new EN Standard for Daylighting of buildings suggest recommendations which will also take into account climatological aspects in daylighting design. The aim of this study is to point out the main differences between the recently used Slovak standard and the proposal of its potential replacement. The paper focuses to that parts of the standards, which are dedicated to the calculation of the Daylight Factor, while the methods are tested especially for attic spaces.

Effects of Smoke on Evacuation

Smoke is often presents during a fire. It affects efficiency of evacuations in buildings. Slovakian national standards do not consider any fire products in evacuation calculations. The paper presents results of evacuation calculations with considerations of smoke. Calculations are done with the evacuation model buildingEXODUS on a hotel building. Results show that prolongation of evacuation time is up to 162%. Results show that the prolongation of evacuation time is up to 162 %, and also show the prolongation of evacuation time do not necessary depend on size, but on position of smoke.

Analysis of Summer Overheating in Elementary School Building

In elementary school buildings, a risk of summer overheating occurs due to large windows which secure and high quality of daylight. It leads to large solar gains. The article analyzes an effect of sun-shading design interacting with ventilation modes for the internal air temperature. Analysis was done with simulation calculation. Results show that the maximum temperature does not fall below θai = 28°C in any case of all alternatives and combinations. In this case, cooling is necessary.

Effect of Air Heating System Distribution on Temperature Stratification in a Room

Most of air heating and ventilating systems for passive houses inlet air in floors. It is assumed that a natural motion of air is led upwards, and so the right stratification of temperature in the space is ensured. However, in the case of excellently insulated buildings it is possible to assume that an upper inlet of air is also able to ensure the required layering of temperature. Within the experiment an influence of upper and down air inlet for temperature stratification in the space was followed. Night sensors of indoor air temperature are placed for measurement purposes. Measurements are done in the long term. The results from measurements show that both, vertical and horizontal stratification of temperature in rooms of passive houses are equal regardless of the fact, which system of air inlet is used.

The Results of Experimental Chamber Temperature Measurements for a Light-Weight Wooden Envelope

Considering the ambitions of passive buildings to achieve net zero values with regard to environmental impacts, it is likely that the trend in the construction of wooden houses will increase. A climate chamber was built with a representative light-weight wooden envelope in Košice to answer the question of how wooden cladding would behave in real-world conditions. The paper describes the progress of temperatures in the light-weight wooden structure situated in the peripheral wall of the experimental chamber. The data obtained will serve as a basis for verification of simulation models and their optimization in the design of the envelope. The aim is to verify the accuracy of measurement data and the expected behaviour of the wooden construction envelope in terms of internal and surface temperatures of the construction.