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The quest for a sustainable built environment brought dramatic changes to architectural design because of the integrated design process. The integrated design process is the modern way to realize “performance architecture,” that is, design with a view to field performance. Integrated design process permits merging of concepts from passive-house designs, solar engineering, and an integration of the building enclosure with mechanical services. In part 1 of this series, the emergence of many new multi-functional materials was discussed. Yet, current innovation is guided by lessons from history. Thermal mass in heavy masonry buildings allowed periodic heating. The authors postulate integration of a hydronic heating system with the walls and the use of smart temperature control of the heating system to modify and optimize the thermal mass contribution. To use the mass of a building, one must accept transient temperature conditions where the indoor temperature varies but is confined by comfort requirements for both summer and winter conditions. On the other side, resiliency requirements dictate that in the absence of electricity the air temperature does not fall below about 12°C over a period of several hours. This requirement implies that summer cooling will likely be separated from the heating systems and that operation of a low-energy building is heavily dependent on the design of smart control systems. Analysis of control systems provided in this article for earth-to-air heat exchangers and cooling of houses with lightweight walls lead us to the requirements of separation between heating and ventilation and needs for different sources of fresh air. Finally, a new concept emerges. [ABSTRACT FROM AUTHOR]

The bacterial and archaeal community composition and the possible carbon assimilation processes and energy sources of microbial communities in oligotrophic, deep, crystalline bedrock fractures is yet to be resolved. In this study, intrinsic microbial communities from six fracture zones from 180-2300 m depths in Outokumpu bedrock were characterized using high-throughput amplicon sequencing and metagenomic prediction. Comamonadaceae-, Anaerobrancaceae- and Pseudomonadaceae-related OTUs form the core community in deep crystalline bedrock fractures in Outokumpu. Archaeal communities were mainly composed of Methanobacteraceae-affiliating OTUs. The predicted bacterial metagenomes showed that pathways involved in fatty acid and amino sugar metabolism were common. In addition, relative abundance of genes coding the enzymes of autotrophic carbon fixation pathways in predicted metagenomes was low. This indicates that heterotrophic carbon assimilation is more important for microbial communities of the fracture zones. Network analysis based on co-occurrence of OTUs revealed the keystone genera of the microbial communities belonging to Burkholderiales and Clostridiales. Bacterial communities in fractures resemble those found from oligotrophic, hydrogen-enriched environments. Serpentinization reactions of ophiolitic rocks in Outokumpu assemblage may provide a source of energy and organic carbon compounds for the microbial communities in the fractures. Sulfate reducers and methanogens form a minority of the total microbial communities, but OTUs forming these minor groups are similar to those found from other deep Precambrian terrestrial bedrock environments. [ABSTRACT FROM AUTHOR]

The microbial diversity in oligotrophic isolated crystalline Fennoscandian Shield bedrock fracture groundwaters is great but the core community has not been identified. Here we characterized the bacterial and archaeal communities in 12 water conductive fractures situated at depths between 296 and 798m by high throughput amplicon sequencing using the Illumina HiSeq platform. The great sequencing depth revealed that up to 95 and 99% of the bacterial and archaeal communities, respectively, were composed of only a few common species, i.e. the core microbiome. However, the remaining rare microbiome contained over 3 and 6 fold more bacterial and archaeal taxa. Several clusters of co-occurring rare taxa were identified, which correlated significantly with physicochemical parameters, such as salinity, concentration of inorganic or organic carbon, sulphur, pH and depth. The metabolic properties of the microbial communities were predicted using PICRUSt. The rough prediction showed that the metabolic pathways included commonly fermentation, fatty acid oxidation, glycolysis/gluconeogenesis, oxidative phosphorylation and methanogenesis/anaerobic methane oxidation, but carbon fixation through the Calvin cycle, reductive TCA cycle and the Wood-Ljungdahl pathway was also predicted. The rare microbiome is an unlimited source of genomic functionality in all ecosystems. It may consist of remnants of microbial communities prevailing in earlier conditions on Earth, but could also be induced again if changes in their living conditions occur. In this study only the rare taxa correlated with any physicochemical parameters. Thus these microorganisms can respond to environmental change caused by physical or biological factors that may lead to alterations in the diversity and function of the microbial communities in crystalline bedrock environments. [ABSTRACT FROM AUTHOR]

This paper presents the inclusion of path based pedestrian environment factors in the San Francisco's CHained Activity Modeling Process model. The factors capture environmental determinants of utility beyond travel time and cost for walking and transit modes with a level of accuracy not previously exhibited in a major agency travel demand model. The paper describes the method for generating the environment factors, discusses which environment factors were found to be significant predictors of walking and transit use, and offers sample interpretations of estimated coefficients using actual livability projects in San Francisco. [ABSTRACT FROM AUTHOR]

Components of the research program jointly sponsored by the Institute for Re search in Construction, National Research Council of Canada, and the Polyurethane Division, Society of the Plastics Industry of Canada, are described. The program is designed to improve the means of evaluating and comparing the value-in-use of various residential thermal insulation materials and systems. To assess value-in-use of insulations such as glass fibre, cellulose, and spray-applied products of which sprayed polyurethane foam is one, the performance of the building envelope as a system, in addition to analysing the materials and components, will be considered. Elements of the program will include:• thermal and energy performance,• contribution of the insulation to the air and vapour barrier performance of the en velope system,• interaction with other building components,• changes in the material performance with time. [ABSTRACT FROM PUBLISHER]

This note describes a test method for determination of air flow resistance of exterior membranes and sheathings. The test specimen is placed between two chambers with different air pressures and the volumetric air flow rate through it at a steady state is determined. The relevant experimental quantities can presently be measured with precision better than 0.5% and with an accuracy of 2 to 3%, using commercial instruments. However, the instrumental precision does not mean much, due to the uncertainty introduced by material variability normally occurring in commercial products. This aspect of the test method is studied and a practical test procedure is suggested. [ABSTRACT FROM PUBLISHER]

A New test method for water absorption proposed for inclusion in the ASTM Book of Standards has been subjected to test series by seven laboratories using four rigid thermal insulating materials. This note presents a statistical analysis and addresses general questions concerning evaluation of the test method uncertainties. [ABSTRACT FROM PUBLISHER]

In a review of laboratory tests of moisture absorption, three methods are carefully examined and compared. Comparisons of laboratory and field data, generally conceded to be the best way to evaluate laboratory test methods, led to the conclusion that moisture gain in perimeter insulation cannot be predicted accurately by any one laboratory test, but that relative assessment is possible from the results of a combination of tests. This paper reviews the state of the art, in particular the work of the ASTM task group on moisture absorp tion. [ABSTRACT FROM PUBLISHER]

A semi-empirical model for calculating heat transfer in dry mineral fiber in sulations takes into account parameters that characterize both the structure of the fibrous material and the boundary conditions in standard laboratory testing. It permits adjustment of experimental data for changes in specimen density or thickness, mean temperature or temperature gradient, i.e., all the uncertainties involved in sampling and testing procedures. [ABSTRACT FROM PUBLISHER]

Information and techniques regarding the proper use of blown mineral fibre insulation are presented. [ABSTRACT FROM PUBLISHER]

The achievement of good thermal performance of cellulose fibre insulation applied in exterior walls is discussed. [ABSTRACT FROM PUBLISHER]

The achievement of good thermal performance in horizontal applications of cellulose fibre insulation is discussed. [ABSTRACT FROM PUBLISHER]

A decade ago, Geo-solar Exergy Storage Technology (GEST) was introduced as a means of utilizing natural, diurnal and seasonal transfers of exergy between a building and its surroundings to significantly decrease heating and cooling requirements. This is accomplished by retrofitting the structure with a dynamic skin to the existing building enclosure that is provided with internal conduits to carry air and fluids, for coupling geothermal storage surrounding the building with the exterior environment. This system was developed by engineers as an affordable, low-tech solution for providing seasonal heat storage in cold climate regions. Meanwhile another holistic but high-tech means to the same goal was initiated by an international group of building scientists by defining concepts for environmental quality management (EQM). Using heat pumps, ‘smart controls’, and newly developed wall coating materials, a fully integrated HVAC (plus moisture control and indoor air quality (IAQ)) system was proposed. The experience gained with GEST methods is now combined with the leading edge of Building Science to permit our international team to re-evaluate the concept of Geo-solar Exergy Storage and Dynamic Building Enclosure incorporated in a system with a heat pump as a new basis for retrofitting buildings in any climate.

The concept of environmental quality management has been described in papers [1 - 4] that looked at the next generation of low energy buildings from the point of view of the occupant. Optimizing energy use is difficult for a few reasons: presence of dramatic changes in the manner we design and operate buildings, change in the role of an architect who must be a leader of interacting team, often quality management is biased towards the design more than on performance of the finished product and finally the need for integrated monitoring and modeling in the occupancy stage. Effectively, we are integrating heating/cooling and ventilation with the structure at the same time as we verify the appropriateness of the new methods to evaluate performance of these systems. In this process we require double controls, one by the occupant and the other by the computerized (smart) control system. The traditional approaches to modify human behavior generally failed because occupants were not given enough control over their environment. Thus, a major part of the trend to a low-carbon, climate resilient future will be focused on methodology to include path from a complex field testing of building performance to simplified testing that combined with simple monitoring and data from utilities would allow assessment of the energy and carbon emission in a district of a city. Our experience shows that preliminary design must be optimized during the period of service for all more complex buildings such as large residential, office or commercial buildings. In this context the artificial neural network approach appears to have significant advantages. Yet, traditionally ANN requires large data set to establish functional relations during the learning stage and therefore the first question is how precise can the control of temperature be when the heat exchanger is subjected to different climatic conditions.