CONCLUSIONS 6

6. CONCLUSIONS

6.1 GENERAL CONCLUSIONS

In comparison with the rest of the spaces at the AA premises, the computer labs are unique and have very specific requirements, which was an interesting point of research and analysis for the whole team. The fact that these rooms generated more heat due to appliance loads increased the need for heat loss, which became our major focus throughout the project. We also had to bear in mind some of the other issues like security, inadequate daylight, stuffiness due to lack of natural ventilation and find appropriate solutions. Finding the right balance between occupant comfort and maintaining the efficiency of the systems at a certain temperature was a key approach for our research and design.

To begin with, our spaces comprising of two computer labs and a courtyard, outdoor studies were carried out for the latter. These detailed studies included the solar, daylight, wind, and comfort analysis which gave us a better understanding of the general spatial characteristics and how the space can be used at its optimum. The base case analysis which included wind flow studies showed inadequacy in the wind distribution due to obstruction by high-rise buildings surrounding the AA. Hence introducing natural ventilation became one of the primary design solutions for all cases.

From studies regarding indoor spaces, which included daylight, we concluded that there is a need for artificial lighting in the computer labs, as direct sunlight would create issues of glare. However, summer and winter solutions have been provided in such a way, where the use of artificial light can be displaced. With regards to the thermal performance of all the spaces, the base case was studied in detail with the help of spot measurements, data logger measurements, surveys by various occupants, analyzing the occupancy pattern which helped us conclude that the spaces can be free-running for some parts of the year, however mechanical cooling and heating would also be a requirement. Finally, computational simulations helped determine the annual performance of the computer labs. After studying various cases and possibilities, several design solutions were made to improve the indoor air quality which in turn improved occupant comfort.

For summer conditions, it was observed that the computer labs with maximum occupancy would be overheated. Unless well designed with an adaptive approach, mechanical cooling would be needed to a greater extent. Hence providing natural ventilation and usage of HVAC as and when needed during operational hours through a combination of louvered and fixed windows was proposed.

Similarly for winter conditions, mechanical heating would be required along with night shutters for insulation during operational hours, in a way, where heating loads were significantly displaced.

Overall the project was concluded with a series of individual technical studies by each team member, taking into account the general performance of the spaces and ones take away from the entire research and analysis of project.

6. CONCLUSIONS

6.2 SPATIAL CONCLUSIONS

New Yard

The spaces on the southwest side of the building are between courtyards, a narrow street, and other mid-rise buildings. This condition potentially creates overshadowing, particularly in lower levels of the building. Therefore, the new yard faces the same challenges.

After carrying out certain fieldwork measurements and computational analysis the team came to certain conclusions:

- There is no direct sunlight available as the courtyard is blocked by three-story buildings.

- The walls surrounding the courtyard are painted white, which helps with light reflectance but has lower illuminance levels compared to other outdoor spaces.

- The temperature of the courtyard is relatively higher than the outdoor Bedford square temperature due to lack of heat dissipation.

- Shadow mask analysis of the new yard shows the visibility of the sky is obstructed by the surrounding buildings.

- Solar radiation analysis shows that the space does not receive adequate direct sunlight and is mostly shaded throughout the day.

- Wind analysis shows that the space receives very low wind velocity due to obstruction from the surrounding building

- Comfort analysis shows that the space experiences heat stress during summer and would be cold during the winter and spring durations.

Hence, based on the above-given analysis for various parameters, the team proposed certain solutions in order to increase comfort conditions. The retractable glass roofing creates an atrium and increases the potential daylighting in the space.

Computer Lab 01

After analyzing some restraints and carrying out spot measurements for temperature, humidity, illuminance, and air velocity in the computer lab along with thermal and daylight analysis the following observations were made:

-With having one side of fixed windows and the other side restrained from opening due to operable blinds, there is a lack of natural light and ventilation.

-Mechanical cooling is provided, set to a temperature of 18°C prioritizing the performance of the systems, however, the spot measurement taken indoors were in a range of 20°C to 25°C.

-After carrying out a few surveys, we found that the occupants were cold due to mechanical cooling.

-To get a comfort range along with displacing mechanical load, attention must be given to increasing the heat loss.

-The relative humidity decreased as the day passed by due to the presence of mechanical ventilation.

-CO2 level measured from 400PPM to 430PPM

As per the thermal analysis and existing cases, the team came to the following conclusions:

-as observed for the existing case, there was a significant amount of energy consumption due to HVAC.

-Comparing this condition with the computer lab 02 which was free running, necessary simulations were conducted.

-These simulations showed a significant decrease in temperature on a freerunning mode during summers, by providing additional natural ventilation, keeping the issue of security as an important aspect.

Computer Lab 02

After carrying out spot measurements for temperature, humidity, illuminance, and air velocity for the computer lab, the team came to the following conclusions:

- The temperature in the lab was relatively high due to the absence of mechanical cooling and heat generated by the systems resulting in low relative humidity.The indoor-outdoor temperature difference was around 8°C to 10°C

- Taking into consideration the volume of the space and heat generated by the computers, lack of fresh air circulation and natural light was observed.

- The relative humidity remained constant throughout the day since the space is ventilated naturally.

In terms of improvising the thermal and daylight conditions in the room following conclusions were made:

- For the skylight case, an adequate amount of daylight was achieved along with retaining the indoor temperature by changing glazing properties and providing stack ventilation.

-The indoor temperature for free running was found to be well within the recommended comfort band.

Introduction Overview Outdoor Indoor Conclusions References Appendices

6.3 TECHNICAL STUDIES 6. CONCLUSIONS

Courtyard

The New Yard is a relatively moderate-sized courtyard on the basement level on 16 Morwell Street with an area of 128.50 m2. It is generally used for large-scale installations and other model work by students throughout the year. To comprehend the occupant's comfort levels in the courtyard: Solar Access, Thermal Studies, and Universal Thermal Climate Index were analyzed. Solar Radiation and Overshadowing analysis revealed that the New Yard received little direct sunlight throughout the year. Additionally, the Universal Thermal Climate Index UTCI indicated that for the most part of the year, that courtyard is in comfort range (9C-26C) however, occupants may experience cold stress and thermal discomfort at certain times from November to April.

In order to improve the thermal efficiency during these cold periods, a retractable glass roof was proposed. This system was designed to retract during summer during comfortable outdoor temperatures while closed during winters to retain the heat generated by adjacent spaces and store solar heat gains. We calibrated the thermal efficiency of the courtyard in relation to the roof height and glazing type. Two variations of roof heights restrained by adjacent buildings and window openings were considered: one at level 0, with a floor-toheight ratio of 1:0.33, and the other at level 2, with a floorto-height ratio of 1:0.65. The roof system at level 0 retains more heat and reduces heat loss, thereby enabling a more comfortable environment. While the roof system at level 1 conserves less heat gain compared to the volume of the space, evident in thermal studies.

In terms of glazing, Double Low-E Argon glass with a U-value of 2.08 W/K and Triple Low-E Argon glass with a U-value of 1.58 W/K were considered. The Triple Low-E Argon glazing had a significant impact on the thermal performance of the courtyard during winters by retaining the heat. In conjunction with the roof height, triple glazing at level 0 resulted in higher thermal efficiency of the New Yard. However, given the purpose of the space, the most suitable design strategy is the retractable roof with triple glazing at level 1. It is appropriate for prominent installations and projects carried out in the space.

Thermal Insulation in Glazing

The study of IT labs at the Architectural Association broadened our understanding of the different elements within the building that play a crucial role in reducing energy consumption while maintaining occupants' comfort. Thermally insulated glazing is one such element that can potentially improve the energy efficiency of windows and make the building occupants more comfortable in both winters and summers. For the purpose of calibrations, thermally insulated Low-Emissivity and Argon Gas glazing were used. Argon gas being less conductive than air when filled in a double or triple glazing unit between two panes, acts as a thermal blanket by reducing the heat loss from the inside during winter and heat gain from the outside during summer. When used in conjugation with Low-E, a microscopically thin coating that reflects heat in the space rather than allowing it to escape through the windows, the glazing provides a more comfortable temperature throughout with lessened energy consumption.

In 'Computer Lab 01' and 'Computer lab 02', Double Low-E Argon glazing was used as additional insulation with a U-value of 2.08 W/K, replacing the single insulated glazing units in the IT labs to understand the impact of glazing on thermal comfort. Moreover, 50mm thick night shutters with thermal conductivity of 0.04W/mK were used as an additional insulating material to prevent heat loss through the windows. They could be retracted during the day for natural light and ventilation while acting as insulation during the night when closed. These modifications and changes in both labs resulted in a significant improvement in comfort hours and energy consumption during summer and winter, evident in thermal simulations. For instance, the simulations indicated a 31.5% energy saving in winter for computer lab 01 with this solution.

For the new yard, a retractable glass roof was proposed. The thermal performance of both Double (U-value of 2.08 W/K) and Triple (U-value of 1.58 W/K) Low-E Argon glazing in the roof was analyzed. There was a substantial improvement in the comfort hours in the case of the triple glazing unit. To conclude, these studies have expanded my understanding of thermal insulation in glazing units and insulation as a whole.

Ventilation through Windows

The outcome of this project is a combination of multiple studies and observations which helped me with an in-depth understanding of the parameters involved in the design process. Keeping in mind the spaces (computer labs), heat generation by the appliances was identified as one of the major reasons for occupant discomfort. Providing adaptive opportunities became the main focus in terms of research and design strategies that were introduced to improve the thermal performance of the spaces. One of the key solutions was the introduction of natural ventilation. This helped not only in increasing heat losses but also in maintaining indoor air quality and temperature.

As a part of the technical studies for the bigger computer lab, a contingency design strategy of mechanical ventilation and cross natural ventilation with louvered windows was developed, along with sliding windows on one side (New Yard) and fixed on the other side (Morwell Street) due to security reasons. Louvered windows can be made secure and still have a high ventilation capacity however increases ventilation loss in winter, which acted as an advantage for the computer lab. Due to the temperature differences between indoor and outdoor, there is a pressure created, which in turn drives the air from one space to another. It is important to note that, optimum performance of this system is possible only if the ventilators are not obstructed. As observed from the previous studies, there was not enough wind for wind-driven systems, hence introducing mechanical cooling was inevitable, yet displaceable.

The necessary parameters were added to the simulations, like an air exchange of 8 l/s, per person. Furthermore, using natural ventilation for a particular temperature limit, resorting to mechanical cooling only if the temperature rose above 24, keeping in mind, maintaining the efficiency of the systems. For computer lab 02 which was free running, similar parameters were added, with an approach to enhance the wind flow by stack roof ventilation as an adaptive design strategy. These systems are typically made of a louvered terminal, a base, and damper assemblies that allow the user to adjust the ventilation (Dejan Mumovic et al,2013). In conclusion, developing certain operating patterns can contribute to the whole adaptive comfort system.

Solar Control

In this study, solar control is one of the critical aspects of analyzing the environmental comfort of the computer lab. To reach the equilibrium between visual, thermal, and daylight considerations, strategies adaptive for glare prevention and effective light distribution to the depths of the lab are proposed

Sun path study shows that majority of the sunlight is received from the South Façade. However, the narrow street flanked by tall buildings hinders light from reaching the lab on the ground floor. The replacement of the single glazing windows with microscopically thin, transparent, pyrolytic double Low-E coated argon fixed glass increases the daylight in the space and modulates the balance between visible and invisible transmittance, allowing 67% solar heat gain and 78% visible light. Due to the absence of shutters and mullions, the glass is supported only on the sides, in turn providing a comparatively larger surface area for light penetration. Furthermore, its ability to permit short wave infrared energy from outside and reflect long wave interior energy assists in preventing the loss of heat during winter, as well as glare and overheating of the space.

The addition of louvers as night shutters in fenestrations allows reflection of incident daylight as the material of the louvers is acrylic and can be manually operated to optimize daylight. The louvers can also function as light diffusers during the day. Light shelves of 300mm are also introduced to reflect incident sunlight into the room.

Additionally, in computer lab 02, with the existing skylight which is sealed with a wooden panel being replaced by rigid pyrolytic coated double Low-E argon-glass, a significant change can be observed in obtaining illuminance levels ranging between 300-500 lux and minimal glare as recommended for a computer lab. This condition holds for more than 30% of the year with varying sky conditions.

Overall, it can be understood that solar control although necessary, in a condition such as this, where the computers in the lab emit a certain amount of light from the screen, allow the user to be able to work in a comfortable visual atmosphere irrespective of the various technical strategies applied to the room.

6. CONCLUSIONS

6.4 PERSONAL OUTCOMES

The opportunity to study IT labs at the Architectural Association provided me with a better insight into the complexity of sustainable environmental design and the role various elements comprising a space play in creating a thermally efficient and comfortable environment.

In several ways, this project was both intriguing yet challenging. Observation on a daily basis was crucial in understanding the IT labs and the New Yard. It helped me comprehend the functioning and experience of the spaces beyond the instruments and calibrations. Furthermore, each lab had several problems concerning high energy consumption and thermal comfort. For instance, Computer Lab 01 uses an HVAC system to maintain a constant temperature within the space, even on weekends resulting in higher energy consumption. Several simulations and computations like MInT and thermal studies enabled me to understand the impact of different elements and solutions on the given spaces. It was particularly helpful in developing different design strategies that could be valuable for various spaces in several conditions. Furthermore, throughout this project, I realized that it is not critical to use only sophisticated mechanisms, but even simple solutions and adaptive opportunities like opening windows could help achieve the required comfort levels. In the case of Lab 01, the use of a mixed mode including natural ventilation to cool the space can significantly impact the thermal comfort while reducing energy consumption.

In general, these analyses and studies widened my knowledge about eco-conscious designs and the importance of thermal efficiency while laying the foundation for further investigations.

Throughout Term 1 Project | IT Labs, understanding environmentally conscious design and the role of different elements composing a building in occupants' comfort has widened. In addition, the different tools, studies, and analyses helped comprehend the different performancerelated variables within the building.

The various calibrations and simulations further helped understand the impact of windows, glazing type, infiltration, and insulation on the thermal performance of a space. They further helped develop different strategies to reduce energy consumption and increase occupants' comfort. For instance, in IT Labs, one of the primary things to tackle was heat gain by the systems and the occupants, which resulted in temperature rise. Mixed-mode ventilation systems, such as HVAC during operating hours and natural ventilation during the rest, were proposed to help minimize energy usage in Computer Lab 01. However, using the existing skylight for stack ventilation in Computer Lab 02 helped lose heat gains by systems and occupants. Moreover, it made me realize that simple solutions could significantly impact the performance of the building.

In general, this project has proved to be highly crucial in laying the foundations for further research and investigations in sustainable environmental design.

The term 1 project, has been a scholastic experience as a whole. It has made me understand in-depth, all that goes into designing a sustainable, energy-efficient space. Through the different research and analytical approaches that were taught to us, there has been a learning curve and a better understanding of the process. From the fieldwork analysis, I have acquired knowledge on how to form the basis of our study. Interviewing the staff, conducting spot measurements and surveys, making observations on the outdoor environment, analyzing an occupancy pattern helped me understand the characteristics of the computer labs, their requirements along with identifying the issues. I was intrigued by the amount of energy consumption that takes place in IT labs, taking into account, maintaining the efficiency of appliances. However, it was also observed that resorting to simple adaptive changes in design as well as the clothing of occupants can have an impact on energy savings. The idea was to displace mechanical cooling or heating as much as possible than eliminate it. Moving on to computational analysis, the tutorials and lectures helped me strengthen my skills as a designer and correlate these studies to our spaces. Through a series of calibrations, the team was able to identify various indoor conditions throughout the year. Taking this into account, conclusions were drawn, in the form of design strategies like introducing natural ventilation and changes to the existing condition like improving the glazing properties, which in turn helped improve the indoor environmental performance along with occupant comfort. Understanding the relation between indoor-outdoor environments and adapting to the shift in these temperatures became the main focus of the studies. I would like to conclude by acknowledging my team members, who helped me understand the importance of collaboration, and for the information exchange that helped the project become a success.

The study of the computer labs and new yard in Architectural Association is unique as they are new additions to the refurbished existing structure and provide an intriguing glimpse at higher energy demand when compared to the already energy-efficient structure.

Specifically, the comparison of the two computer labs was of heightened interest to me. Both spaces even though in the same building, behave differently with varying occupants, volumes, equipment, fenestration, and orientation. The computer labs can be marked as both the hottest and coolest space in the building since heat is dissipated from all the equipment, but the temperature can be controlled to make the space cold. Providing stronger evidence to support our fieldwork through simulations enabled me to integrate various parameters for analysis and further develop strategies for improving the building's efficiency. By observing the relationship between outdoor analysis and indoor performance of computer labs integrating daylight and thermal studies, I was able to bridge the gap between ambition and reality. Multiple adaptive strategies for various conditions of the year, catering to different comfort levels thermally and visually in the different spaces were developed. The study concludes that solutions provided in free-running mode could work better than the current scenario with the use of simple adaptive opportunities, bringing a balance between daylight and thermal comfort for the majority of the year.

As a designer, I see the opportunity to address most of the challenges mentioned throughout this report by applying design strategies that can co-exist with most of our functional, analytical and aesthetical ambitions, thus realizing that design can be truly integrated and energyefficient.