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There are a large number of indicators that use CO2 concentration as parameter to assess air stuffiness and, consequently, to asses IAQ. Their comparison is difficult since they are not usually linked to each other. The aim of this article is to compare the results of 10 CO2-based IAQ indicators and determine if they classify a house in a similar way during heating seasons. We propose a method to normalize the results based on the reference values of each indicator, and we highlight the sensitivity of the indicators to the choice of one occupancy scenario among several possibilities. The database used contains the CO2 concentration measured over 2–3 years in the living room and the parental bedroom of three new and occupied nearly-zero energy houses in France (COMEPOS project) with low-cost probes sampling every minute. The results indicate that the IAQ of the same house in the same heating season can be classified differently depending on the indicator and threshold chosen. Moreover, an indicator can show different results for the same room over the years. For example, the IAQ of the bedroom of House 2 is classified poor in 2017 and 2019 but good in 2018 according to the mean CO2 concentrations with a 1000-ppm threshold. The indicators also present different levels of sensitivity to occupancy scenarios, being the cumulative exposure the most sensitive by increasing up to 257% without an occupancy scenario, which highlight the importance of the systematic implementation of a standard occupancy scenario for the CO2-based IAQ performance indicators.

http://iconarp.selcuk.edu.tr/iconarp/article/view/62, Climate change has drawn the attention of many researchers and practitioners to focus on the methods to address the challenges in achieving low-carbon buildings and cities and in future developments. Nevertheless, few studies have explored the impacts of thermal mass applications for the lowest carbon emissions of building operational energy consumption. A comparative study of CO2 emissions due to different wall and floor compositions is presented in accordance with their lifespans for a hot-humid climate site. Aim of this study is to examine the relation between the energy oriented operations and carbon emissions of the building. Firstly, an existing low-rise building in İzmir is selected, then modelled in the dynamic simulation model software DesignBuilder v4 by synchronizing drawings with basic operational principles of the program. Furthermore, various influence factors of building envelope thermal characteristics are selected as follows: type, location, thickness and thermal specifications of materials used by keeping thermal conductivity value constant. At the end, the research presents remarkable influence of thermal mass oriented measures on reducing energy demands and carbon footprints.

Binaların opak ve saydam yüzeyleri enerji kayıp ve kazançları açısından önemli bir role sahiptir. Binalarda, pencerelerden kaynaklanan güneş enerjisi kazanç ve ısı kayıp miktarları, pencere/duvar alanı oranı, cam tipi ve çerçeve gibi özelliklere bağlıdır. Enerji etkin tasarım bağlamında ısıtma ve soğutma amaçlı enerji tüketimine olan etkisi nedeni ile pencerelerden kazanılan güneş enerjisi ve kaybedilen ısı miktarının, erken tasarım aşamasında yerel iklim koşullarına göre analiz edilmesi gereklidir. Bu çalışmada, sıcak-nemli iklim koşullarına sahip İzmir ilinde bulunan bir eğitim binası incelenmiştir. Farklı cam türleri için farklı yönlerdeki pencere/duvar alanı oranı değişiminin enerji tüketimine olan etkisi, enerji analiz programı EnergyPlus kullanılarak karşılaştırılmıştır. Elde edilen simülasyon sonuçlarına göre binalarda pencere/duvar alanı oranı, yön ve cam tipinin enerji tüketimi üzerinde etkili olduğu görülmüştür. Farklı yönlerdeki pencere/duvar alanı oranının %10’dan %60’a artırılması durumunda ısıtma amaçlı enerji tüketimindeki azalma, güney cephedeki değişime bağlı olarak maksimum, doğu cephesinde ise minimum düzeydedir. Soğutma yükü açısından ise güney cephedeki değişimin yine en yüksek değere, kuzey cephedeki değişimin ise en düşük değere neden olduğu saptanmıştır. Toplam enerji tüketimi açısından (ısıtma + soğutma) doğu ve batı cephelerin en etkili, kuzey cephenin ise en az etkiye sahip olduğu hesaplanmıştır. Çift cam (mevcut) yerine low-e kaplamalı cam kullanıldığında ise yönlere göre sıralamanın değişmediği görülmüştür. Kısacası bina enerji performansına etkisi olan parametrelerin, mimari tasarım sürecinin erken aşamalarında veya mevcut binaların enerji etkin iyileştirilmelerinde, enerji analiz programları aracılığı ile değerlendirilmesi, enerji etkin çözüm önerilerinin oluşturulmasına önemli katkılar sağlayacaktır., The opaque and transparent surfaces of buildings have an important role in the total percentage of energy loss or gain. Heat loss or gain from windows are dependent on the window-towall area ratio, the window glass type, and the type of window frame used. In the concept of energy efficient design, heat loss or gain from windows should be analyzed in detail in the early stages of building design by considering local climatic conditions. This study investigates a school building located in Izmir in Turkey, a city with a hot and humid climate. Various glass types with different glazing characteristics and number of layers, located in different parts of the buildings and with different window-to-wall ratios are analyzed and compared using building the energy analysis program “EnergyPlus”. Results indicate that window- to-wall area ratios, wall orientation and glass types are important factors in the building’s total energy consumption. When the window-to-wall area ratio is increased from 10% to 60%, the winter heating load of the building decreases in maximum amount on the south side of the building and reduces in minimum amount on the east side of the building. When summer cooling load is investigated the highest increase in energy consumption is found on the south side of the building. On the eastern and western sides of the building the effect of increased energy consumption value remains low. When the total energy consumption (cooling + heating) is considered, it is calculated that the east and west sides have the biggest total effect and the northern wall has the smallest total effect. When low emissivity glass is used instead of double layer glass, in terms of energy consumption the building side order of effect remains the same, although actual values differ. It is therefore clear that using energy analysis programs to analyse different factors within the energy consumption of buildings will be beneficial in creating energy efficient solutions. This can be carried out in the earlier stages of the architectural design of the buildings or at the renovation stages of existing buildings.