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Housing Conditions and Children's Respiratory HealthWells, John A. 27 March 2014 (has links)
Understanding how respiratory health risks are associated with poor housing is essential to designing effective strategies to improve children’s quality of life. The objective of this thesis is to determine the relationship between the respiratory health of children and the condition of the homes in which they reside – using both building science and health data. The thesis therefore, examines the association between self-reported mould in the home, housing conditions, and the respiratory health of children. The study contributes to both the medical and engineering research community by enabling researches, designers, and Building Code officials to focus on cost-effective target areas for improving indoor air quality and thus, the respiratory health of children.
A survey designed to assess the relationship between respiratory health and housing conditions was completed by 3,424 parents of grades 3 and 4 children in Winnipeg, Manitoba, Canada. Air samples were then taken in the homes of a subset of 715 houses– one in the child’s bedroom and another in the basement – with an exterior neighborhood air sample as a control measure. Engineering audits on 715 homes were then conducted – including measurements of relative humidity, temperature, and moisture content of walls.
Major findings include the following: (1) Self-reported visible mould in the home is clearly associated with the presence of air-borne mould. (2) There are fewer healthy children when mould is present in the home. (3) Cladosporium levels (CFU/m3) in the house were associated with children’s asthma in combination with persistent colds. (4) Measures taken by homeowners to increase the air-tightness of their homes, such as new windows increased the likelihood of having higher air-borne moisture and mould levels. (5) The “hygiene hypothesis” was supported, which postulates that denying children access to certain types and levels of biological contamination at a young immune-developmental age, increases their susceptibility to allergic responses at a later age.
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Questioning the envelope conceptGokhale, M. Unknown Date (has links)
No description available.
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A study on thermal comfort and energy performance of urban multistory residential buildings in MalaysiaSabarinah Sh. Ahmad Unknown Date (has links)
No description available.
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Design guidelines for indoor comfort in row houses in hot-humid climatesTakkanon, P. Unknown Date (has links)
No description available.
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Design guidelines for indoor comfort in row houses in hot-humid climates.Takkanon, Pattaranan Unknown Date (has links)
Many countries in hot-humid regions cope with rapid urbanisation. Land cost becomes higher especially in high-density areas. There is a demand of residential and commercial buildings due to the economic growth in the cities. Row house became a popular building type since it combines both functions in one place. A large amount of row houses are found in Bangkok, Thailand. Despite their versatility, they are not properly designed for the climate and urban conditions. The occupants adopt air conditioning systems to control indoor comfort whereas row houses are not properly designed for the installation of the airconditioners. This increases the energy demand. This research aims to establish appropriate design guidelines and recommendations to ensure indoor comfort in urban row houses in hot-humid climates. Thermal comfort is the main concern apart from others such as visual, acoustic and indoor air quality. Thermal stress should be minimised by primarily passive means as long as possible and the building design should also provide the flexibility for operating active systems whenever they are required. To achieve this aim, it is important to assess indoor conditions in existing row houses to provide a basis of comparison. A case study in Bangkok has been selected for a field investigation during the hottest month of the year to examine how the case study responds to the critical condition. Flow visualisation tests have been conducted to compare the results of indoor air velocity to those of the field investigation. Computer simulations have been carried out to investigate and compare the performance of design variables affecting indoor comfort such as orientation, zone location, roof and wall materials, aperture schedules, and shading devices. Two blocks of 4-level row houses have been simulated and three units: an intermediate and two units at the both ends of the row have been examined. There are two sets of the simulations: naturally ventilated and air-conditioned cases. Then, the design guidelines and recommendations are developed based on the results from the two series of simulations. Results from the 3-day field investigation show that indoor conditions of the case study are overheated. The indoor temperatures are slightly lower than To during the day while they are higher than To during the night. These results correspond to those of simulation runs for a verification study. The wind tunnel test shows low indoor air velocities. It is recommended to install ceiling fans to increase the wind speed enough to generate cooling effect. The level of interior illuminance drops with distance from the window. It should be improved by installing artificial light sources in the area far from the opening. The sound levels exceed the noise control limit at all times. Results from the simulations for the naturally ventilated and air-conditioned row houses show some similarities. In the former, internal conditions of the occupied units are above the comfort limit almost all day. Orientation is a crucial factor affecting the indoor thermal condition. The front of a row house should face either north or south and the end unit with east-facing side wall performs better than that with west-facing side wall. The worst orientation is generally west but the east could be worse for the end unit with south-facing side wall at such an orientation. The effect of zone location is also related to the orientation. The intermediate unit is more sensitive to design variables since it generally shows the biggest T difference between the variants with the best and the worst design factors. Aperture schedule has a great effect on indoor conditions for naturally ventilated cases. Closing windows during the day could keep the zone cooler than opening the windows which would admit the hot air from the outside. Concrete flat roof with ceiling insulation gives the best results while metal sheet roof gives the worst. Concrete block with acoustic board performs best for both naturally ventilated and air-conditioned buildings while the worst wall type is aerated concrete in cases of the naturally ventilated buildings and common brick wall in cases of the air-conditioned ones. However, the results from the effect of roof and wall material study show that adding insulation could improve the indoor condition more effectively than changing the roof and wall materials. An additional height from the mezzanine floor only affects the thermal performance of the room on ground floor. In comparison to the row house without mezzanine floor, the presence of mezzanine slightly increases indoor temperature in naturally ventilated cases while increases cooling load of the room on the ground floor drastically in air-conditioned cases. Shading devices should be designed particularly for each orientation since their effects are tremendous once applied to the opening to protect it from solar radiation. The limited distance between the front of row houses and the street as allowed in the existing building regulations should be extended for the devices to provide enough shading for the building.
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Design guidelines for indoor comfort in row houses in hot-humid climates.Takkanon, Pattaranan Unknown Date (has links)
Many countries in hot-humid regions cope with rapid urbanisation. Land cost becomes higher especially in high-density areas. There is a demand of residential and commercial buildings due to the economic growth in the cities. Row house became a popular building type since it combines both functions in one place. A large amount of row houses are found in Bangkok, Thailand. Despite their versatility, they are not properly designed for the climate and urban conditions. The occupants adopt air conditioning systems to control indoor comfort whereas row houses are not properly designed for the installation of the airconditioners. This increases the energy demand. This research aims to establish appropriate design guidelines and recommendations to ensure indoor comfort in urban row houses in hot-humid climates. Thermal comfort is the main concern apart from others such as visual, acoustic and indoor air quality. Thermal stress should be minimised by primarily passive means as long as possible and the building design should also provide the flexibility for operating active systems whenever they are required. To achieve this aim, it is important to assess indoor conditions in existing row houses to provide a basis of comparison. A case study in Bangkok has been selected for a field investigation during the hottest month of the year to examine how the case study responds to the critical condition. Flow visualisation tests have been conducted to compare the results of indoor air velocity to those of the field investigation. Computer simulations have been carried out to investigate and compare the performance of design variables affecting indoor comfort such as orientation, zone location, roof and wall materials, aperture schedules, and shading devices. Two blocks of 4-level row houses have been simulated and three units: an intermediate and two units at the both ends of the row have been examined. There are two sets of the simulations: naturally ventilated and air-conditioned cases. Then, the design guidelines and recommendations are developed based on the results from the two series of simulations. Results from the 3-day field investigation show that indoor conditions of the case study are overheated. The indoor temperatures are slightly lower than To during the day while they are higher than To during the night. These results correspond to those of simulation runs for a verification study. The wind tunnel test shows low indoor air velocities. It is recommended to install ceiling fans to increase the wind speed enough to generate cooling effect. The level of interior illuminance drops with distance from the window. It should be improved by installing artificial light sources in the area far from the opening. The sound levels exceed the noise control limit at all times. Results from the simulations for the naturally ventilated and air-conditioned row houses show some similarities. In the former, internal conditions of the occupied units are above the comfort limit almost all day. Orientation is a crucial factor affecting the indoor thermal condition. The front of a row house should face either north or south and the end unit with east-facing side wall performs better than that with west-facing side wall. The worst orientation is generally west but the east could be worse for the end unit with south-facing side wall at such an orientation. The effect of zone location is also related to the orientation. The intermediate unit is more sensitive to design variables since it generally shows the biggest T difference between the variants with the best and the worst design factors. Aperture schedule has a great effect on indoor conditions for naturally ventilated cases. Closing windows during the day could keep the zone cooler than opening the windows which would admit the hot air from the outside. Concrete flat roof with ceiling insulation gives the best results while metal sheet roof gives the worst. Concrete block with acoustic board performs best for both naturally ventilated and air-conditioned buildings while the worst wall type is aerated concrete in cases of the naturally ventilated buildings and common brick wall in cases of the air-conditioned ones. However, the results from the effect of roof and wall material study show that adding insulation could improve the indoor condition more effectively than changing the roof and wall materials. An additional height from the mezzanine floor only affects the thermal performance of the room on ground floor. In comparison to the row house without mezzanine floor, the presence of mezzanine slightly increases indoor temperature in naturally ventilated cases while increases cooling load of the room on the ground floor drastically in air-conditioned cases. Shading devices should be designed particularly for each orientation since their effects are tremendous once applied to the opening to protect it from solar radiation. The limited distance between the front of row houses and the street as allowed in the existing building regulations should be extended for the devices to provide enough shading for the building.
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Measuring Pixels: Using Grasshopper to Evaluate Thermal Bridges in BuildingsDirks, Ryan 18 August 2015 (has links)
Green design is now a ubiquitous term in the profession of architecture, yet the energy performance of buildings in real-world conditions is poorly documented. A large number of buildings use substantially more energy than is predicted during design, and one possible explanation is that designers do not adequately understand the impact of thermal bridging through insulation on the energy use of a building. This study proposes a methodology that uses the parametric design program Grasshopper to quantitatively analyze infrared images for the degree of thermal bridging in a wall assembly. The end result is a user-friendly tool that architects can use to study the relative energy performance of their buildings in the field, giving them an increased understanding of the energy efficiency of their designs. Case studies of various details show a ten to fifty-five percent reduction in the effective R-value of the overall wall assemblies due to thermal bridging. / 10000-01-01
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Moisture Movement and Mould Management in Straw Bale Walls for a Cold ClimateBronsema, Nicholas Rangco 27 September 2010 (has links)
There is a growing interest in straw bale construction for its low embodied energy and
insulation value. Early studies of its structural behaviour and fire resistance have shown it to
be a viable alternative to traditional building techniques. However, the biggest remaining
obstacle to widespread acceptance is the moisture behaviour within the straw bale walls,
especially as it concerns mould growth. The uncertainty of this behaviour leads to the
hesitation of building officials and insurance providers to freely accept straw bale
construction. Therefore, this study investigates the moisture, temperature and mould growth
in straw bale walls, through a combination of analysis, dynamic modeling and field studies.
A study of mould is presented along with the current methods available for predicting mould
growth.
Moisture is the primary controllable factor to mould growth in buildings. Therefore, an
understanding of moisture accumulation within straw bale walls is necessary to provide a safe
design that precludes mould growth. This study compiles the current state of knowledge of
the hygrothermal properties of the materials used in straw bale walls. Then a parametric
steady-state analysis is conducted to show the expected behaviour of vapour diffusion and the
effects of the material properties.
Two 14”thick x 6’ wide x 8’ high straw bale test walls were constructed: one was rendered
with a typical cement-lime plaster and the other with a clay plaster. Temperature and
moisture were monitored throughout the walls for over a year. These test walls provide more
information on the macro behaviour of the walls to both vapour diffusion and, more
importantly, rain.
Hygrothermal computer modeling was conducted and compared to the test data to assess its
accuracy. Thermal modeling was successful, while moisture modeling was found to be more
difficult due to a lack of accurate rain data. With better climate data it is expected that
accurate hygrothermal modeling of straw bale walls is possible.
The result of this work is a general starting point for more detailed studies of the
hygrothermal behaviour of straw bale walls with the ultimate goal of assessing the mould risk
for various construction techniques and locations.
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Moisture Movement and Mould Management in Straw Bale Walls for a Cold ClimateBronsema, Nicholas Rangco 27 September 2010 (has links)
There is a growing interest in straw bale construction for its low embodied energy and
insulation value. Early studies of its structural behaviour and fire resistance have shown it to
be a viable alternative to traditional building techniques. However, the biggest remaining
obstacle to widespread acceptance is the moisture behaviour within the straw bale walls,
especially as it concerns mould growth. The uncertainty of this behaviour leads to the
hesitation of building officials and insurance providers to freely accept straw bale
construction. Therefore, this study investigates the moisture, temperature and mould growth
in straw bale walls, through a combination of analysis, dynamic modeling and field studies.
A study of mould is presented along with the current methods available for predicting mould
growth.
Moisture is the primary controllable factor to mould growth in buildings. Therefore, an
understanding of moisture accumulation within straw bale walls is necessary to provide a safe
design that precludes mould growth. This study compiles the current state of knowledge of
the hygrothermal properties of the materials used in straw bale walls. Then a parametric
steady-state analysis is conducted to show the expected behaviour of vapour diffusion and the
effects of the material properties.
Two 14”thick x 6’ wide x 8’ high straw bale test walls were constructed: one was rendered
with a typical cement-lime plaster and the other with a clay plaster. Temperature and
moisture were monitored throughout the walls for over a year. These test walls provide more
information on the macro behaviour of the walls to both vapour diffusion and, more
importantly, rain.
Hygrothermal computer modeling was conducted and compared to the test data to assess its
accuracy. Thermal modeling was successful, while moisture modeling was found to be more
difficult due to a lack of accurate rain data. With better climate data it is expected that
accurate hygrothermal modeling of straw bale walls is possible.
The result of this work is a general starting point for more detailed studies of the
hygrothermal behaviour of straw bale walls with the ultimate goal of assessing the mould risk
for various construction techniques and locations.
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Parametric Analysis and Life Cycle Cost Assessment for Optimizing PCM Application in Exterior Walls in the Kingdom of Saudi ArabiaAlamri, Uthman Abdullah 19 December 2024 (has links)
The Kingdom of Saudi Arabia (KSA) aims to reduce CO2 emissions and mitigate its environmental impact as part of Vision 2030. The building sector has high energy consumption, particularly due to elevated cooling demands, which make up 70% of residential energy use. This is largely caused by uninsulated thermal mass and subsidized electricity rates. In addition, Vision 2030's housing projects and labor shortage necessitate alternatives to current housing standards. Modular housing offers a solution to the labor shortage, but its success depends on lighter materials. This study proposes replacing thermal mass with PCM in modular housing and, investigates this using EnergyPlus simulations. The research investigated the optimal placement and thickness of PCM to maximize its thermal performance in SIPs. PCM application reduced the model total site energy by 12.9% to 13.7% with a thickness of 0.5–2.0 cm and significantly reduced the HVAC energy consumption by 37% to 39%. In this study, we developed LCCA models to assess the cost-effectiveness of PCM by establishing a price range per square foot that aligns with the energy savings that are usable in the KSA. This study also identified the maximum PCM production cost based on the LCCA analysis to ensure its investment use in KSA's construction industry. / Doctor of Philosophy / KSA's Vision 2030 aims to reduce CO2 emissions and minimize environmental impact. The building sector brought researchers attention since the energy used in the residential type accounts for 70% of the energy for cooling. The cooling demands it because of the lack of proper insulation in buildings and the low electricity rate. The country aims under Vision 2030 to advance its housing projects and faces a labor shortage. The modular housing proposed in this situation represents a promising solution to KSA. However, modular homes need to be built with lighter materials, and this study explores the potential of replacing traditional heavy building materials with PCM in modular homes. PCM helps control indoor temperatures by absorbing and releasing heat, improving energy efficiency. The research used the energy simulation method to investigate and determine the optimal placement and thickness of PCM within SIPs. PCM utilization reduced the model total site energy by 12.9% to 13.7% when using a thickness of 0.5–2.0 cm PCM layer, which decreased HVAC energy consumption by 37% to 39%, respectively. The study also assessed the cost-effectiveness of PCM by determining a price range per square foot that aligns with the energy savings required for practical use in the KSA. Additionally, the maximum production cost of PCM was identified to ensure it is a worthwhile investment in the country's construction industry.
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