This book is about the optimization of the characterization of the thermal properties of building envelopes, through experimental tests and the use of artificial intelligence. It analyses periodic and stationary thermal properties using measurement approaches based on the heat flow meter method and the thermometric method. These measurements are then analysed using advanced artificial intelligence algorithms. The book is structured in four parts, beginning with a discussion of the importance of thermal properties in the energy performance of buildings. Secondly, theoretical and experimental methods for characterizing thermal properties are analysed. Then, the methodology is developed, and the characteristics and properties of the algorithms used are explored. Finally, the results obtained with the algorithms are analysed and the most appropriate approaches are determined. This book is of interest to researchers, civil and industrial engineers, energy auditors and architects, by providing a resource which improves energy audit tasks in existing buildings.

This book is about the optimization of the characterization of the thermal properties of building envelopes, through experimental tests and the use of artificial intelligence. It analyses periodic and stationary thermal properties using measurement approaches based on the heat flow meter method and the thermometric method. These measurements are then analysed using advanced artificial intelligence algorithms. The book is structured in four parts, beginning with a discussion of the importance of thermal properties in the energy performance of buildings. Secondly, theoretical and experimental methods for characterizing thermal properties are analysed. Then, the methodology is developed, and the characteristics and properties of the algorithms used are explored. Finally, the results obtained with the algorithms are analysed and the most appropriate approaches are determined. This book is of interest to researchers, civil and industrial engineers, energy auditors and architects, by providing a resource which improves energy audit tasks in existing buildings.

This book results from a Special Issue published in Energies, entitled “Building Thermal Envelope". Its intent is to identify emerging research areas within the field of building thermal envelope solutions and contribute to the increased use of more energy-efficient solutions in new and refurbished buildings. Its contents are organized in the following sections: Building envelope materials and systems envisaging indoor comfort and energy efficiency; Building thermal and energy modelling and simulation; Lab test procedures and methods of field measurement to assess the performance of materials and building solutions; Smart materials and renewable energy in building envelope; Adaptive and intelligent building envelope; and Integrated building envelope technologies for high performance buildings and cities.

Concrete is widely used in buildings as a structural and finish material and mix designs for these applications are well established. The thermal properties of concrete are also embedded in a number of building envelope design strategies but mix designs to optimize for these performance characteristics are not generally considered. In this study, specific heat capacity, thermal conductivity, and compressive strength of concrete mixes were investigated and a mix design strategy for optimizing thermal performance of concrete in building envelopes was developed. Portland cement and geopolymer cement concrete mixes were compared for this application. Generally geopolymer cement concrete mixes were determined to be more suitable for thermal optimization.

The design and construction of the appropriate building envelope is one of the most effective ways for improving a building’s thermal performance. Thermal Inertia in Energy Efficient Building Envelopes provides the optimal solutions, tools and methods for designing the energy efficient envelopes that will reduce energy consumption and achieve thermal comfort and low environmental impact. Thermal Inertia in Energy Efficient Building Envelopes provides experimental data, technical solutions and methods for quantifying energy consumption and comfort levels, also considering dynamic strategies such as thermal inertia and natural ventilation. Several type of envelopes and their optimal solutions are covered, including retrofit of existing envelopes, new solutions, passive systems such as ventilated facades and solar walls. The discussion also considers various climates (mild or extreme) and seasons, building typology, mode of use of the internal environment, heating profiles and cross-ventilation Experimental investigations on real case studies, to explore in detail the behaviour of different envelopes Laboratory tests on existing insulation to quantify the actual performances Analytical simulations in dynamic conditions to extend the boundary conditions to other climates and usage profiles and to consider alternative insulation strategies Evaluation of solutions sustainability through the quantification of environmental and economic impacts with LCA analysis; including global cost comparison between the different scenarios Integrated evaluations between various aspects such as comfort, energy saving, and sustainability

Along with improvement in buildings structure, developments in thermal design allow decreasing the energy demand of heating, cooling, and air conditioning of buildings. This thesis distinguishes and optimizes design elements that are essential in minimizing building heating/cooling loads. Optimum designs vary significantly for different areas due to different meteorological conditions between locations and seasonal changes at the same location. Considering the typical meteorological conditions at two sites, a genetic algorithm optimizer is coupled with annual simulations of building energy demand to minimize building energy use. The results present significant deviations between annual optimum design and ideal design for hot or cold season. The findings emphasis the importance of year-long simulations in optimal thermal design of buildings.

With recent emphasis on reducing building energy consumption, tools are needed that can determine the overall performance of building thermal envelopes in a manner that is accurate, efficient, and accessible. Two such methods--one experimental and one numerical--were developed for the evaluation and optimization of building thermal envelopes at the University of Wisconsin- Madison. A Rotatable Guarded Hot Box (RGHB) apparatus was designed and constructed for the large-scale thermal testing of post-frame building envelope designs. In addition to conducting standard thermal performance tests in accordance with ASTM C1363, the apparatus--capable of testing a wall or roof specimen up to 2.9 x 3.8 m--was designed to simulate the effects of air infiltration through the application of a static pressure differential across the test specimen. Utilizing a cable winch system and centralized pivot point, the entire apparatus may be rotated 360 degrees about its horizontal axis to test wall or roof specimens at any orientation. Using this apparatus, the thermal effect of various envelope design changes such as structural component placement and orientation, insulation type and geometry, and the inclusion and placement of air barriers may be studied. This apparatus employs an automated computer control system that acquires and stores temperature, pressure, air speed, and relative humidity data; varies heater and fan output; calculates and records key variables; and determines the completion of experimental objectives. Using this system, it is possible to expedite the conduction of accurate thermal experiments with a minimum of human interaction. The thermal performance of nine post-frame thermal envelopes was studied and optimized using a computational fluid dynamics model validated experimentally by the rotatable guarded hot box. In addition to providing thermal performance values for typical wall designs, this study proposed a new wall design that greatly increased thermal performance without sacrificing material efficiency. Study variables included structural geometry, level of insulation, and the presence and placement of radiant barriers. To reduce computational demand, modeling was primarily conducted using an area-weighted average of two-dimensional slices to represent three-dimensional assemblies. After modeling a portion of the assembly in three dimensions and comparing it with its two-dimensional counterpart, this simplification was found to result in less than a 6.7% error. Significant error (up to 57%); however, was determined to be integral to the simplifying assumptions commonly used by building designers, especially in envelopes common to the agricultural industry. This error was estimated to underpredict energy costs for a 2,200 m^2 cold-storage warehouse in Wisconsin by approximately $1,700 a year. The combination of these two distinct methods allows investigation of the effects that a wide array of factors have on the thermal performance of a building envelope. Through the investigation of these individual factors, thermal envelopes as a whole may be optimized for sustainability, based on a balance of the efficient use of energy, material, and labor.