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.

No description available.

No description available.

No description available.

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.

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.

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

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.

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.

The primary objective of this study was to investigate mould growth resistance of different types of wood products which include the sheathing and framing within full scale wall assemblies. Secondary objectives were to investigate the difference in mould growth resistance between borate-treated and untreated wood products as well as provide information about mould growth under different temperature and humidity conditions for treated and untreated wood products. <br /><br /> The objective of the study is to better understand mould growth, and to examine the effects of varying high moisture conditions on wooden products and the mould growth which may result. More importantly this will be examined on full scale wall assemblies; to date mould growth studies have only been performed within a laboratory on small samples of materials. Moreover, this study recreates the conditions which evidently cause mould growth on full scale wall assemblies. Tests were performed within a climate chamber on three full scale wall assemblies. The original scope of this study included an examination of the sheathing and framing components within a full scale wall assembly, however this study will focus mainly on the sheathing. <br /><br /> Results of this study indicate that the relative humidity conditions needed for mould growth on wood are higher than originally believed (i. e. , significantly greater than 80%RH). During the first eight weeks of test number one the relative humidity at the surface of the sheathing was held constant at 95% and little mould growth was observed on the untreated sheathing (mould growth index of 3 or less); little or no mould growth on the treated sheathing (mould growth index of 1 or less). The second and third tests demonstrated that the presence of liquid water greatly accelerated the time to germinations, the amount of mould growth (up to a mould growth index of 6), and the rate of mould growth. All three tests clearly showed that borate-treatment reduced the amount of mould growth; however, the concentration of borate-treatment, and the types of materials treated, does affect the resistance of mould growth. Furthermore, there was some evidence to suggest Borate treatments of the plywood increased the time to germination significantly, from a few weeks to 16 weeks in this study, but once mould growth was initiated, the rate of mould growth was similar to that of the untreated plywood. Two mathematical models to determine mould growth were examined: Viitanen and WUFIBIO (Sedlbauer). Viitanen?s model predicted time to germination and rate of growth rate well for untreated plywood, and WUFIBIO predicted time to germination but not the growth rate. It was also found both models err on the side of caution in predicting mould growth. <br /><br /> Recommendations include improvements to the test method and producers, and for future work.