The design of a building's exterior walls has an important influence on energy consumption, building cost and thermal comfort. It influences also heating and cooling devices’ size. Optimization of energy consumption of the building requires consideration of the building materials, their thickness and mass, type and thickness of insulation, and location of the insulation layer. The correct way to optimize all the above parameters is a calculation of temperatures and energy consumption in a dynamic process, which means considering changes every few seconds. This may be done only with a computer program. It is not easy to gain expertise in such programs. In addition, submission of input values to the program is time consuming and frustrating process, which many times ends with errors. This work introduces the term “Thermal Time Constant” which may be applied to determine the thermal quality of the building as an alternative to the dynamic simulation program. The Thermal Time Constant method is much easier, simpler and faster than a computer dynamic simulation program. Higher Thermal Time Constant (TTC) moderates the difference between day and night in the room, flattening the room temperature extremes caused by ambient temperature and solar energy. Higher TTC is not necessary necessarily more expensive. To take advantage of high TTC is not so the question of additional investment, but the question of understanding the TTC concept. In some cases consideration of TTC caused changes to the building's design and construction technique, bringing benefits to the contractor, the tenants and the national economy. Disregarding TTC leads to wrong decisions, wrong design, waste of money on building construction and increased energy consumption.

Thermal Time Constant (TTC) indicates the time required for change of 63.2% of temperature difference. This work develops useful application of TTC for determination of temperature change in buildings. Higher TTC results in slower change of room temperature, contributing to thermal comfort, to quality of the building and to energy conservation. The procedure developed in the work is for both purposes: to find the temperature change in the period of time and to find the period of time of specific temperature change.

Design of building's exterior walls has important influence on energy consumption, building cost and thermal comfort. It influences also heating and cooling devices size. Optimization of energy consumption of the building requires consideration of the building materials, their thickness and mass, type and thickness of insulation, and location of the insulation layer. The correct way to optimize all the above parameters is calculation of temperatures and energy consumption in dynamic process, which means considering changes every few seconds. This may be done only with computer program. It is not easy to gain expertise on such programs. In addition, submission of input values to the program is time consuming and frustrating process, which in many times ends with errors. This work analyses if the Thermal Time Constant method may be applied to determine energy quality of the building as an alternative to the dynamic simulation program. The Thermal Time Constant method is much easier, simpler and faster than computer dynamic simulation program. Few examples of exterior wall design were selected to calculate the energy consumption and room temperatures. Two locations were selected for the calculations, one with moderate summer and the second with moderate winter. The dedicated dynamic simulation computer program was applied to gain data regarding the energy consumption, maximum and average room temperatures for south facing room and for north facing room at each location. Thermal Time Constant reflects the thermal inertia and thermal mass of the building. Higher Thermal Time Constant (TTC) moderates the difference between day and night in the room, flattening the room temperatures extremes caused by ambient temperature and solar energy. Higher TTC is not necessary more expensive. To take advantage of high TTC is not so the question of additional investment, but the question of understanding the TTC concept. In some cases consideration of TTC caused changes to the building's design and construction technique, bringing benefits to the contractor, to the tenants and to the national economy. Disregarding TTC leads to wrong decisions, wrong design, waste of money for building's construction and increased energy consumption.

Climate Considerations in Building and Urban Design Baruch Givoni Climate Considerations in Building and Urban Design is the most comprehensive, up-to-date reference available on building and urban climatology. Written in clear, common-sense language by Baruch Givoni, the leading authority in the field, this book is a far-reaching look at a variety of climatic influences and their effects on individuals, buildings, and communities. Aimed at architecture and urban planning professionals and students alike, Climate Considerations in Building and Urban Design offers real-life solutions to climatological site planning and design issues, helping to settle disputes about site orientation, site organization, and the assembly of building materials. Climate Considerations in Building and Urban Design is organized into three parts. The first, Building Climatology, analyzes human thermal comfort and the effect of architectural and structural design features including layout, window orientation, and shading, and ventilation conditions on the indoor climate. Then, Urban Climatology explores the ways in which the climate in densely built areas can differ from surrounding regional climactic conditions, for example, in temperature, wind speed, and humidity. This part further explores the effects of urban design elements, such as urban density and building height, on a city's outdoor climate. Finally, Building and Urban Design Guidelines applies the body of available research on building climatology and the effects of physical planning on the urban and indoor climates to suggest design guidelines for different regions--for example, hot-dry and hot-humid climates. Filled with lists, tables, and graphs for easy cross-referencing, as well as hundreds of visuals, Climate Considerations in Building and Urban Design offers readers the ability to perform a quick check of a proposed scheme against authoritative criteria. Mr. Givoni's latest volume is a unique, indispensable guide to the relationship between building design, urban planning, and climate.

Passive and Low Energy Ecotechniques (PLEA) presents the proceedings of the Third International PLEA Conference held in Mexico City, Mexico on August 6-11, 1984. The book includes papers on state-of-the-art selected topics aimed at providing a basic knowledge; country and regional or personal monographs to continue the exchange of national information which is an established feature of PLEA; and position papers for the topic seminars. The text also presents papers on vernacular shelter and settlement; case studies of new buildings and retrofits, urban and community planning and design, photovoltaic systems implementation, cooling systems, modeling and simulation, guidelines and tools for design and planning.