Tianyu Feng
LEED Green Associate
Writing Sample Bachelor of Architecture NAAB Accredited & CACB Certified Iowa State University, Ames, Iowa, U.S.A. Email: tyfengpro@gmail.com tianyu.feng@ryerson.ca Phone: 1+416-956-8647 Address: 33 Bay Street, Unit 302, Toronto, Ontario, M5J 2Z3
Table of Content 01. Remote Desert Research Station Solar Energy, Climate Responsive Design, Energy Modelling Summer, 2014 Tucson, AZ
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02. Evaluation of the King Pavilion Indoor acoustic,Ventilation, Shading Device, and Thermal Mass Fall, 2013 Ames, IA
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03. The Building Envelope Failure of Western Berlin Congress Hall Building Facade Assembly Spring, 2013 Ames, IA
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Remote Desert Research Station Author: Tianyu Feng Professor: Kris Nelson Date: Summer, 2014
Abstract To utilize natural and renewable energy in modern architecture is becoming a dominant research direction. The remote desert research station (RDRS) is designed with a unique hypothesis of utilizing solar energy and rain water in Saguaro National Park, Tucson, Arizona, which is in an extremlydry and hot climate condition. As a summer studio project, the design had been finished within 7 weeks including a one-week field trip to Phoenix-Tucson area, Arizona. The main objective of this project is to design a pilot Remote Desert Research Station (RDRS) in the western portion of Saguaro National Park. A specific site wasn’t assigned, therefore, the project of the station would be considered to fit in a general condition in the park. The RDRS will be staffed by 6 University of Arizona students, faculty, and/or staff. Researchers will gather soil, water, and plant samples, tag and track wildlife, and record geographic information. The RDRS will serve as “home base” and staging point for extended field research excursions and will provide for temporary data and specimen storage. No main power or water will be transported to the site. which means the energy and water usage of RDRS should be self-sufficient with all required set of energy and water catchment systems. As it serves for university staffs, the RDRS will not be operated during the hot summer months of June to August. The RDRS must be designed to be secured from vandalism, animals and weather during this unoccupied period. The design will be approached from biomimicry as a design methodology. Through 3.6 billion years of evolutionary trial and error, nature has developed and perfected the design of a wide variety of systems, structures, processes and materials. The extreme climatic conditions of the desert represent clear design drivers and hold rich potential for formal, material, and strategic architectural response. The study of biological and built forms evolved in response to the desert climate will serve as the foundation of studio research.
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Introduction The remote desert research station (RDRS) is located at a western part of Saguaro Nation Park, Tucson, AZ. The climate of Tucson, Arizona is extremely dry with dramatic daily temperature swings. During summer, the average temperature could reach up to 100 °F. During winter, the average temperature could drop to 40 °F. To achieve the passive energy standards, it needs to consider both heat gain/loss conditions in different seasons. The average annual participation in Saguaro National Park is 12.18” (30.25 cm), which needs to feed a huge water catchment area to collect enough water to meet the yearly needs. In addition, it is beneficial to preserve buildings and create possibility to cool down the building by creating humidity.
Average Annual Precipitation
Average Annual Temperature
In order to truly learn from native architecture and the habits of local living beings, we visited precedent examples during the field trip, including modern architecture, historic relics and natural parks. When we were at the Phoenix area, we visited the Burton Barr Library designed by Will Bruder and Arabian Library designed by Richärd+Bauer in Scottsdale. As the representative modern architecture in this area, both buildings are designed to respond the local climate. The central core surrounded by the non-accessible pond in Burton Barr Library(Image1 and 2) accelerates the air flow by utilizing solar chimney effect and cools down the building by increasing the humidity within it. The east and west sides of the building are covered with a double façade to reduce the heat gain from solar radiation. The double height top floor is designed to pull up hot air and speed up ventilation. A sky light provides enough natural light to readers during daytime hours. The Arabian Library is designed as a spiral shape from floor plan. It creates a shading effect by utilizing the building itself (Image 3). Also, low windows are mostly located on the south elevation to avoid excessive sun light. On the north elevation, large windows are designed to accept ample soft natural light. We also visited Pueblo Grande Ruins at Phoenix and Casa Grande Ruins near Tucson (Image 4). In ancient times, people constructed the adobe walls extremely thick, which is a good application of thermal mass from modern perspective. It could keep the room temperature consistent all year round. The sizes of windows is minimized (about 1’ x 1’/30cm x 30cm) to gain the least amount of heat while admitting an acceptable level of natural light. Within the ruins complex, the most important room is usually elevated to second floor and in the central area of the complex. It could prevent the room from being radiated by solar heat directly or absorb heat from ground. It could also avoid heat loss when outdoor temperature is low. In the Desert Botanical Garden, we figured most of the living beings could survive in the extreme climate by residing underground, covering with thick furs/skin or unique food habit. The most impressive animals is the desert tortoise. The shell protects the internal soft body. At the same time, the dome shape accelerates air flow inside of the shell and expels heat. During winter, the shell helps the body stay warm. From the trip, I figured out that there are numerous representative characteristics from precedent studies that could be applied toward my design. In passive energy architecture the most dominant strategies are to accelerate air flow, pull out hot air when the temperature is high, utilizing solar energy and introduce humidity.
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Image 1. Burton Barr Library South West View
Image 2. Burton Barr Library Performance Diagram
Image 3. Arabian Library Interior, Viewing Out
Image 4. Pueblo Grande Ruins
Design development At the beginning of the design process, I started with a series of research of desert animal and vegetation as required with a biomimicry approach. The most impressive animal to me is the desert tortoise with its shell. As it is shown in the diagram 1, when air comes in the dome shell from a tiny entrance, the air flow will be sped up due the pressure difference. It brings heat away quickly. The ratio of the width of shell to the length of shell is around 1:5, which aligns with the best situation to accelerate the air flow. Finding inspiration in the shell, my initial proposal is to create a super structure shell with four different types of panels to cover it. They are a Photovoltaics (PV) panel, a solar heat collector, a translucent panel, and a high reflective panel (diagram 3). Considering the water collection, all the panels will create a seamless sloped surface to collect water in a large water tank. The roof are mostly tilted down toward the south side with a calculated slope to receive solar energy with PV panels and solar heat collectors.
Diagram 1 Inspiration
The PV panels absorb solar energy which is converted into electricity. The energy will provide basic lighting, radiant space heat in winter and power for lab equipment, such as refrigerator and small operation light. Solar heat collectors would directly heat up water to provide basic hot water usage. In order to prevent glare, the translucent panels are designed to filter intense natural light and 3
create a comfortable luminance underneath of the shell. In the desert, people could easily get lost without an obvious way-guiding object. The highly reflective panels on the top of the shell reflect daylight and make the whole building shine in the desert. People could easily find their ways back as they follow the direction of shining landmark. The shell could be regarded as four sections, the tail section, west section, true south section and east section (diagram 2). Most PV panels and Solar Water Collector are located on true south section. Those panels could guarantee the primary energy generation. More PV panels and Solar Water Collectors will spread out on other sections in ideal weather conditions. The intention is to capture more energy when sunlight hits the shell from other directions, which could provide energy to be potential use for heat radiator during winter, operating any lab machines or any unexpected weather changes. The reduction of efficiency is smaller than 10%. The tail of the shell will extend to the ground on west side to avoid glare on the building during late afternoon. At the east side, the shell will shade part of the building due to the different needs for light intensity of the internal programs. Judging from North- South section, the shell extends out from the roof edge more than ½ of the building width on the south side to provide shading for the south elevation. All of the panels are almost equally spread out on the entire shell, which will avoid over-concentrated light. Aesthetically, the pattern creates a sense of flow.
PV Panels
High SRI Panels Way finding tool
Light Reflecter
Solar Water Heater Solar to Hot water
PV Panels Solar to Electricity
Solar Water Heater Transparent Panel
High SRI Material
E 40°
Diagram 2 Panel arrangement
The design of the enclosed building underneath of the shell starts from orientation. As the diagram 4 shows, the dominant wind direction is southeast and northwest. In order to create good ventilation, the main walls of the building are perpendicular to wind direction to potentially receive maximum air flow. The building is two-story structure with a two-story tall central space. It is to pull up heated air from the lower level by utilizing volume and pressure difference. Each single space has windows on both south and north façades, which creates the possibilities of cross ventilation and natural light from different orientations. The size and shape of windows are designed according to orientation. The windows on south side are minimized and lower to the floor level. Only sunlight with a low angle could directly get into the room. The windows are larger on the east side since the morning light is not as strong. The north façade is designed with large windows, and it is also the main natural light resource. The solid wall is fairly thick and mainly made of concrete. It will provide sufficient thermal mass to keep the room temperature relatively consistent. The roof of the building follows the slope of the shell, and the central area is open with skylights.
15°
Diagram 3 Four types of panels
Diagram 4 Wind rose
4
1. Face the wall to dominant wind direction
2. Create a core to ultilize stacke ventilation& solar chimney
4. Elevate North wall, Maximise sunlight
3. Create skylight to light up space with reflected light of the shelter
90d
Diagram 5. Form development
The arrangement of the program is determined due to natural climate conditions and the special needs of each program. As it shows in diagram 6, the living space is arranged at the center space of the first floor. The bedroom space has two alternative choices. The first space is on the east side of the first floor. The intention is to get plenty of morning solar radiation since the shell would only shade a small portion of the first floor. It wouldn’t create too much interruption since the whole building would only staff 6 people at most. During summer, people could also choose to move the bedroom space to the outdoor terrace on the west side of second floor since the west side would be completely covered by the shell. The terrace, with great view and convenient access creates an active social space for the staff at the same. Natural ventilation could create a comfortable outdoor environment even when the temperature is above 75 °F. The lab space is arranged on the east side of the second floor, and it is only half closed from the central core. The main natural light comes from clearstorys window on the north façade.
Bedroom
Living Space
Lab
Summer Situation
Lab Bedroom Living Space
Winter Situation Diagram 6. Program design
Roof Plan Floor Plan --- 1’ = 1/32”
First Floor
5
SecondFloor
Rendering 1 exterior viewing to west side of the building
Solar Energy Usage The most significant factor influencing the installation of PV panel and solar water heater are angles and area. The latitude of Tucson, Arizona is 33º 26' N. According to the MEEB, the most efficient angle for PV panels is “latitude - 15°” when it faces true south. The most efficient angle for solar water collector should be the same. The panels in the calculations are the portion on the true south shell. It will guarantee the greatest energy and hot water generation. The PV panels sitting on other portions of the shell will work as supplement in case the staff needs to use heat radiator during winter, operating any lab machines or to accommodate any unexpected weather changes. The detailed calculation process is listed below. Part I: Calculation of Photovoltaics (PV) panels Step1. List of the regular daily energy usage (unit W hr/day) Living Space Microwave Refrigerator Coffee maker 2 central Lights Bedrooms 6 lights 1 central light Bathrooms 1 light Water pump
11w x 6 x 2hr = 132 W hr
Lab 6 computers 1 lab monitor 6 phone chargers 2 concentrated lights 2 sets of Basic lab equip. Specimen Storage refrigerator
22 x 4hr = 88 W hr
Assume a 10% changing range.
22x 4 = 88 W hr 750 x 4 = 5400 W hr
Total Energy Usage: 36,480 W hr x 110% = 40128 W hr/DAY
700W x 1hr = 700 W hr 540 W x 24hr = 12,960 W hr 800W x 1hr = 800 W hr 22W x2 x 4hr = 176 W hr
40w x 6 x 4hr = 960 W hr 150W x 24hr = 3600 W hr 24 W x 1hr = 24 W hr 110w x 2 x 2hr = 440 W hr 80w x 2 x 4hr = 540 W hr 540W x 24hr = 12,960 W hr
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Step2. Calculate the angle Tucson Altitude is: 33º 26' N The best PV panel angel: 33-15= 18 º True South Step3. Calculate the size of PV panels From the solar radiation chart on MEEB, I could get 1. January: 4.6 kWh/m2/day --- 0.62 kWh/ft2/day Temperature: 10.7°C Monthly Average Incident Solar Radiation: 470 wh/m2/day 2. April: 7.8 kWh/m2/day --- 0.87 kWh/ft2/day Temperature: 18.8°C Monthly Average Incident Solar Radiation: 680 wh/m2/day 3. August: 6.6 kWh/m2/day --- 0.74 kWh/ft2/day Temperature: 29.2°C Monthly Average Incident Solar Radiation: 540 wh/m2/day The three months listed above are the time period of the least, medium, and the most solar radiation. In order to make sure every single month receives enough solar energy, it is better to use the January data since it is the worst case scenario. All the data is based on the 10% efficiency of PV panels, which is the most common type. In order to collect enough rain water, the shell surface is quite large. Considering economic benefit, the highly efficient PV panels wouldn’t be the first choice. 40128 W hr/DAY / 470 wh/m2/ day = 85.4 m2 = 768.4 ft2 Part II. Calculation of Solar Water Collector The only water resource is rain water. The usage of water should be minimized. The portable water is not included since it is considered to be supplied from outside. Step1. List of the regular daily water usage (unit: gallon/day) 5-minute Shower (6 people once per day) 15 gallon x 6 = 90 gallon Others 30 gallon Total Water Usage: 120 gallon
Step2. Calculation the area of water collector According to the MEEB part II, the equation of calculating the amount of heat (Q) is Q (daily heat needed) = 8.33 x gallon per day x (Ts – Tg)
East elevation
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Ts is the storage temperature --- 110 °F Tg is the ground water temperature --- 60 °F Q (daily heat needed) = 8.33 x 120 x 50 = 49980 BTU System efficiency = 0.8 x collector efficiency Collector efficiency: 0.7(the common data) System efficiency = 0.8 x 0.7 = 0.56 Daily insolation = Clear day total x (Average day total / Clear day total) Clear day total: 2356 Average day total: 1874 Clear day total: 2390 Daily insolation = 2356 X (1874/2390) = 1847 BTU/ sq. ft. day Collector area = daily heat needed x percent solar desired / daily insolation x system efficiency Collector area = 49980 x 100% / (1847x 56%) = 48.32 ft2 Facade Sunlight Radiation Study(Vasari) Janurary 21st
April 21st
September 21st
November 21st
Diagram 7. Vasari Facade Study
Water Usage The average annual precipitation is 12.18” (30.25 cm). The roof size should be large enough to collect enough rain water for regular daily usage and create enough shading area for outdoor activities. The roof sizing calculation is as follows. For the sake of ease of calculation, the rain collection portion is divided into 5 pieces (diagram 8 ).
Diagram 8. Roof division
South elevation
8
Area of roof (unit: ft2) 1 2 3
2
2
80 x 29 x ½ = 1160 ft 2 80 x 19 x ½ = 760 ft 2 54 x 39 x ½ = 1053 ft
4 23 x 54 x ½ = 621 ft 2 5 (69 + 43) x 45 x ½ = 2520 ft 2 Total area: 6114 ft
Besides the area of roof, the total daily water usage will also determine the size of water tank. There is plenty of space underneath of the tail of the shell. The clear height is less than 6 feet and wouldn’t be accessible by users. The tank is covered by the tail and half buried into the ground. In order to calculate the size of water tank, the significant factors are Catchment Yield, Usage, Net Water and Cumulative Capacity Adjusted for Actual Size. In most months, the usage of water is more than water catchment. The main water storage heavily relies on June to August and assume taht the water tank is 15,000 gallons. When people leave the station at May, the water remaining is 1677.4 gallon. If the precipitation reduction is less than 0.71” every year, the water storage wouldn’t be affected at all. When the water collection exceeds the volume of the tank, the extra water will be piped out through an overflow.
rea on A
lecti
r col wate Rain
Water Tank
Diagram 9. Rain water collection system
Total water usage (unit: gallon) 5-minute Shower (6 people once per day) 1.6-gallon flush toilet (10 time per day) Others Total Water Usage: 140 gallon
15 gallon x 6 = 90 gallon 1.6 gallon x 10 = 16 gallon 34 gallon
Formula for the calculation 1. Catchment yield = Precipitation x roof area 2. Cumulative capacity adujusted for acutral size= CCAfAS (Former month) + Net water Water tank calculation (unit: gallon) Month & Rainfall July August September October November
2.34" 2.24" 1.18" .86" .62"
Catchment Yield (gallon) 8918.5 8537.4 4497.4 3277.7 1615.0
Usage 0 gal 0 gal 4,200 gal 4,340 gal 4,200 gal
Net Water 8918.5 8537.4 297.4 -922.3 -2588
Cumulative Capacity 8918.5 17455.9
17753.3 16831.0 14243
Cumulative Capacity Adjusted for Actual Size 8918.5 15000 15000 14077.7 11489.7
Longitudinal Section 9
December January February March April May June
.97" .97" .96" .77" .36" .17" .21"
3697 4,340 gal -643 13600 3697 4,340 gal -643 12957 3658.9 4,060 gal -401.1 12555.9 2934.7 4,340 gal -1405.3 11150.6 1372.1 4,200 gal -2827.9 8322.7 647.9 4,340 gal -3692.1 4630.6 800.4 0 gal 800.1 5430.7 3; 2677.6 gallon = 358 ft it give a 0.71� annual precipitation reduction.
10846.7 10203.7 9802.6 8397.3 5569.4 1877.3 2677.4
Building material and assembly The choice of construction material and assembly method could be rather influential to indoor temperature. As it has been discussed before, the walls as valuable thermal mass could protect indoor space from excessive heat gain or loss. The air gap is assembled as a critical component to stop moisture exchange. The interior space is finished with gypsum wall. For the exterior finishing, the coarse concrete stucco is assembled to avoid sunlight reflection, which could avoid the temperature raise around the building. The windows are constructed with triple-panel glass. The two layers of air gaps are sufficient to block the heat transfer. This type of glass could refract sunlight three times, which could also reduce the intensity of the ultraviolet radiation. The roof is unusually thick, assembled with extra insulation to keep the room temperature stable. At the edges of the shell, the water gutter is embedded and flush with the surface of the shell for aesthetic reasons.
Wall section details
Latitudinal section 10
Close up period During June to August, the building would be vacant. In order to keep the vandalism, animals and sandstorms out, another layer of protection is required. For the sake of installation convenience, the cover would be made of 1/16� thick metal sheet. The metal sheet is soft as fabric and strong as regular metal. When people occupied in the building, the metal sheet could be rolled up and hidden under the shell. The metal covering is made of translucent modules and highly reflective modules, which could extend the pattern on the shell. When people leave the building, they could simply pull down the metal sheet and hook it on the deck. The metal sheet will follow the form of the shell and the building, which could seal the building completely. The buffer zone between outdoor and indoor space could avoid direct sunlight radiation indoor facilities and furniture.
Open Season
Pull Down the Metal Sheet
Soft metal sheet sample
Close Down Diagram 10 Metal sheet cover perferance
Rendering 2. Close up Period
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Rendering 3 Interior view to the central core
Conclusion From ventilation, water usage, energy usage and materiality, the Remote Desert Research Station is a comprehensively considered project. As a project base in biomimicry, the RDRS has been inspired from desert tortoise. The RDRS has not only simulated the form and pattern of the tortoise but also learned from how the tortoise’s shell works. As a passive energy structure the RDRS has fully taken advantage of the shell and set up a complete system of solar energy and rain water collection within the special structure. It has greatly reduced the need for imported energy by fully utilizing any native and renewable resources, which is a practical precedent for future energy-efficient architecture.
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Reference 1. Walter T. Grondzik, Alison G. Kwok, Benjamin Stein and John S. Reynolds, Mechanical and Electrical Equipment for buildings- 11th edition, John Wiley & Sons. Inc, Portland, OR, 2010. 2. Liedl Petra, Hausladen Gerhard, Saldanha Michael, Building to Suit the Climate : A Handbook, DE GRUYTER, 2011 3. Perter Forbes, the Gecko’s foot, Bio-inspiration Engineering New Material from Nature, W.W Norton & Company, New York-London, 2005 4. Janine Benyus, Biomimicry Innovation inspired by nature, Harper perennial, the U.S., 1997 5. Biomimicry, Last modifired by Febrary, 9th, 2011, http://biomimicryarch.blogspot.com/2011_05_01_archive.html 6. Biomimicry for designers, “ Where the rubber meet the sustainability road…”, April, 22nd, 2011, http://biomimicryfordesigners.blogspot.com/2011/04/where-rubber-meets-sustainability-road.html 7. Zoomorphic, butterfly house, 2000-2003, http://www.vam.ac.uk/vastatic/microsites/1269_zoomorphic/templatebutterfly.htm 8. Don’t be a PV panel snob September, 21st, 2011, http://physics.ucsd.edu/do-the-math/2011/09/dont-be-a-pv-efficiency-snob/ 9. Architectrue daily, Aribian library, May 1st, 2011, http://www.archdaily.com/130435/arabian-library-richardbauer/ 10. DE BARTOLO + RIMANIC DESIGN STUDIO, phoenix public architecture part 1, http://dbrds.wordpress.com/2011/02/16/phoenix-public-architecture-part-1/ 11. Terran.org, Designing the Passive solar residence, Spring, 2015, http://www.terrain.org/articles/16/michal.htm 12. Clear day hours, http://www.wrcc.dri.edu/htmlfiles/westcomp.clr.html 13. Vincent P. Lonij, Adria E. Brooks, Kevin Koch, and Alexander D. Cronin, Analysis of 80 rooftop PV systems in the Tucson, AZ area, paper access online, http://uapv.physics.arizona.edu/Publications/PVSC2012/Analysis_of_80_rooftops.pdf 14. Weather data, http://www.solardirect.com/pv/systems/gts/gts-sizing-sun-hours.html 15. Climate Consultant, version5.1 16. Bruce Bassler, Architectural Graphic Standards- 11th edition, Chapter 8&12, John Wiley & Sons. Inc, Portland, OR, 2010. 13
Evaluation of the King Pavilion Author: Tianyu Feng Professor: Ulrike Passe Date: Spring, 2013
Background The King Pavilion, designed by RDG in 2009 is organized into a 2-story building with 22,317 total square feet on the north side of the College of Design at Iowa State University. There are seven design studios per floor, which are organized around a central core. As a flexible experimentation and workspace. The central volume allows daylight to penetrate into the lower level of the pavilion. Windows are organized to capture daylight for each studio classroom. During the design phase, the architects were given a goal to create the first LEED Platinum university building in the nation. King Pavilion scored 53 out of 69 possible points in the old LEED ranking system. According to the architect and data collected, King Pavilion is on average 50% more efficient than an average building. Because of the large windows the building is essentially entirely day lit during the day requiring very little electricity. To cool the building and still maintain LEED certification, automatic windows located above the central core automatically operated to allow air to flow in and out of the building via the stack effect. Another important sustainability feature implemented in King Pavilion is the vegetated roof. The roof reduces the heat island affect and reduces storm water needs on the property.
Image 1. Exterior View
Natural Lighting& Shading Deveice Design Temp: 69°F Light: 34 ftc
Temp: 72°F Light: 25 ftc Temp: 70°F Light: 26 ftc Temp: 68°F Light: 27.3 ftc Temp: 71°F Light: 26 ftc Temp: 72°F Light: 22.1 ftc
Temp: 74°F Light: 36.7 ftc Temp: 72°F Light: 28 ftc Temp: 72°F Light: 24 ftc Temp: 71°F Light: 21.4 ftc
Image 2. Basement
Image 3. First Floor
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In order to explore the building in detail, I have detect four important factors of the building, daylight condition, ventilation, temperature and sound condition. The data I have collected with different devices are shown in the floor plan. Through the calculation, the data shows King Pavilion has a 4% day light factor (shown in the image 2 &3) . Also, the data collection from light test devices in a regular day shows 25 foot candles of light at the desk height. This provides an equal amount of lighting throughout the space. Because artificial lights are not needed throughout the day, King Pavilion is 42% more energy efficient than the average building. As students who spend my days (and nights) in the new facility,” can attest that 100% day lighting is not good. The many windows result in large amounts of direct sunlight, which create glare and temperature concerns in southwest facing glass in the hall way of the King Pavilion. Currently, the shading device is not wide and long enough to block the sun from 1pm to 6pm. In order to provide a comfortable interior light condition, I proposed a new shading device on this huge window, as shown in the image 5. Image 4. Solar Angle Chart
H
Image 5. Current West facade
L
12”
w
32”
12 in 26°
Image 6. new shading device
The total area of the window is: A = 32” x 12” x 10 x 13 = 49,920 sq. in. = 346.67 sq. ft. I chosse late August as test time since it is the worst case during school days, the latitude of Ames (42 degrees), and solar radiation intensity in a day, I found that at 4p.m., the solar elevation is 26 degrees so this led to our design of a shading device that would overhang each individual section of the window at a 26 degree angle. From the Image 6, I can see that: L = cos26 x 12in (length of shading device) 15
L = 10.8” H = cos26 x L – 2” = 7.69” (subtracted 2 because of the thickness of mullion) W = sin26 x L = 4.73” Through the sun path chart and diagram, I designed the shading device below. It has an overhang over each section in between each louver and mullion, and I also designed fins at both ends of the window to protect from the sun angles at the sides of the window. According to the MEEB, I found that: SHGF = 106. SCI = 0.87; SCO = 0.5; CLF = 0.7(12pm August 21st, ) So to calculate the cooling load without our shading device, I can plug in these numbers: HG = A x SHGF x SCI x SCO x CLF HG = 346.67 x 106 x 0.81 x 0.5 x 0.7 = 10,417.78 BTU/hour I then calculated the shaded area that our shading device design provides: A = 32” x 12” x 10 x 13= 49,920 sq. in. = 222.16 sq. ft. So to figure out the exposed area, I subtracted the shaded area from the window area before our shading device design was added: 346.67 - 222.16 = 124.51 sq. ft. After I found the exposed area, I calculated the new cooling load for our shading device design: HG = 124.51 sq. ft. x 106 x 0.87 x 0.8 x 0.7 = 8037.62 BTU/hour I then subtracted the new cooling load from the current cooling load to figure out the cooling load reduction: 10,417.78 - 8037.62 = 2380.16 BTU/hour
Thermal Mass I designed a series of the research and calculation process to accurately study the thermal mass of the King Pavilion. Considering the humid and hot summer, I collected the hourly temperature of Ames, IA of the hottest day in order to figure out the temperature difference between outdoor and indoor, which could directly influence the heat transfer.
Table 1. Hourly temperature of June 16th, 2013 (unit: °F)
8:00AM
68
4:00 PM
82
12:00AM
71
9:00AM
70
5:00 PM
80
1:00 AM
70
10:00AM
71
6:00 PM
78
2:00 AM
68
11:00AM
73
7:00 PM
77
3:00 AM
66
12:00PM
75
8:00 PM
76
4:00 AM
65
1:00 PM
76
9:00 PM
75
5:00 AM
64
2:00 PM
78
10:00PM
73
6:00 AM
65
3:00 PM
80
11:00PM
72
7:00AM
66
The heat gain is from three aspects: radiation, conduction, and infiltration. 1. Radiation: I only need to calculate the side of window with direct sunlight, which is the southwest window. From the previous calculation, I’ve learned that the window is double-glazed, clear glass. SHGF = 204 BTU/h sq. ft. (from Table C.3 p.1534 MEEB, it is the for a day.); SCI=0.7; SCO =0.5; CLF=0.7 HG = A x SHGF x SCI x SCO x CLF = (11x30) x 204 x 0.7 x 0.5 x 0.7 = 16,493.4 BTU/DAY 2. Infiltration: It includes sensible heat, latent heat, people, lighting, general equipment, and laptop computers. The type of heat are calculated hourly. The sum of each type of heat will be shown in the Table 2 i. Sensible heat = v x 1.08 x ∆T x (# of people) = 10 x 1.08 x 6 x 120 = (answer is shown in the Table 2) 16
ii. Latent heat = v x 4842 x ∆W x (# of people)=10 x 4542 x 3.3 x120= (ansIr is shown in theTable 2) iii. People: (# of people) x 500 BTU/ person in a day= 120 x 180 x 24 = (ansIr is shown in the Table 2) iv. Lighting: floor area x lighting watts x BTU/h/Watt x 24 = 13,879 x 0.41 x 2.4 = (ansIr is shown in the Table 2) v. General equipment: floor area x equipment watts x BTU/h/Watt X 24h = 13,879 X 0.41 X 2.4 X 24 = (ansIr is shown in the Table 2) vi. Laptop computers: (# of computers) x 375.1 BTU/h x 24h = 80 x 175.1 x 24 = (ansIr is shown in the Table2) Table 2. Infiltration calculation
Time
T
∆T
People Lighting Equipment Laptop
Latent Heat Sensible Heat
8:00 AM
68
-6
0
9:00 AM
70
-4
0
10:00 AM
71
-3
0
11:00 AM 12:00 PM
73 75
-1 1
0 2160
1:00 PM
76
2
4320
2:00 PM
78
4
8640
3:00 PM
80
6
12960
4:00 PM
82
8
17280
5:00 PM
80
6
12960
6:00 PM
78
4
8640
7:00 PM
77
3
6480
8:00 PM
76
2
4320
9:00 PM
75
1
2160
10:00 PM
73
-1
0
11:00 PM
72
-2
0
12:00 AM
71
-3
0
1:00 AM
70
-4
0
2:00 AM
68
-6
0
3:00 AM
66
-8
0
4:00 AM
65
-9
0
5:00 AM
64
-10
0
6:00 AM
65
-9
0
7:00 AM
66
-8 31200 690841
307769
31200 690841
307769
Total Sum of Inflitration
336193
513520
336193
513520
0 77760
2246783
3. Conduction: The following answers are just examples of one hour. Because of the heat change, the situation in 24 hours are different, the specific answer of each single hour will be shown in the chart below. i. Upper floor glass (huge window) ii. Upper floor small windows iii. Upper floor West glass wall iv. Upper floor corner v. Upper floor North and South vacuum walls vi. Upper floor East vacuum wall 17
vii. Upper floor West vacuum wall viii. Lower level glass (huge window) ix. Lower level floor corner x. Lower level floor glass east wall xi. Lower level floor South vacuum walls xii. Lower level floor East vacuum wall
Example Calculation for Conduction for an hour: Time: 4PM; Temperature is 82°F Double-glazed, clear glass - U = 0.64 Vacuum Wall – U = 0.0032 Upper Level North/South Vacuum Wall: Area x U value x delta T = Heat Gain HG = [(11’ x 83’) – 6.5 sq. ft.] X 0.0032 x (82 - 74) = 23.2 BTU Table 3. Conduction- first floor
Sensible Time
∆T
T
8:00 AM
68
Small E Small Corner N/S Vacuum E Vacuum Wall N/S Glass Windows Windows E Glass W Glass Windows Walls
Heat Gain
-6
0
0
0
0
0
0
0
0
0
9:00 AM
70
-4
0
0
0
0
0
0
0
0
0
10:00 AM
71
-3
0
0
0
0
0
0
0
0
0
11:00 AM
73
-1
0
0
0
0
0
0
0
0
0
12:00 PM
75
1
2160
212.5
25
20.8
245.8
577.3
57.6
2.9
3.4
1:00 PM 2:00 PM
76 78
2 4
4320 8640
425 849.9
49.9 99.8
41.6 83.2
491.5 983
577.3 577.3
115.2 230.4
5.8 11.6
6.8 13.5
3:00 PM
80
6
12960
1274.9
149.8
124.8 1474.6
577.3
345.6
17.4
20.3
4:00 PM
82
8
17280
1699.8
199.7
166.5 1966.1
577.3
460.8
23.2
27
5:00 PM
80
6
12960
1274.9
149.8
124.8 1474.6
577.3
345.6
17.4
20.3
6:00 PM
78
4
8640
849.9
99.8
83.2
983
577.3
230.4
11.6
13.5
7:00 PM
77
3
6480
637.4
74.9
62.4
737.3
577.3
172.8
8.7
10.1
8:00 PM
76
2
4320
425
49.9
41.6
491.5
577.3
115.2
5.8
6.8
9:00 PM
75
1
2160
212.5
25
20.8
245.8
577.3
57.6
2.9
3.4
10:00 PM
73
-1
0
0
0
0
0
0
0
0
0
11:00 PM
72
-2
0
0
0
0
0
0
0
0
0
12:00 AM
71
-3
0
0
0
0
0
0
0
0
0
1:00 AM
70
-4
0
0
0
0
0
0
0
0
0
2:00 AM
68
-6
0
0
0
0
0
0
0
0
0
3:00 AM
66
-8
0
0
0
0
0
0
0
0
0
4:00 AM
65
-9
0
0
0
0
0
0
0
0
0
5:00 AM
64 -10
0
0
0
0
0
0
0
0
0
6:00 AM
65
-9
0
0
0
0
0
0
0
0
0
7:00 AM
66
-8
0
0
0
0
0
0
0
0
0
79920
7861.8
923.6
769.7 9093.2
5773
2131.2
107.3
125.1
Total Sum of upper floor
50656
Table 4. Conduction- basement
conner windows Time
T ∆T x4
S Vacuum E Vacuum S Glass E Glass Wall
Wall
8:00 AM 68
-6
0
0
0
0
0
9:00 AM 70
-4
0
0
0
0
0
10:00 AM 71
-3
0
0
0
0
0
11:00 AM 73
-1
0
0
0
0
0
227.8
675.8
3.1
1.2
455.7 1351.7
6.3
2.5
12:00 PM 75
1
57.6
1:00 PM 76
2
115.2
Through the measurement, I figured out that the total floor area and the concrete portion of the wall is 13,879 sq.ft. Also, the thickness of the floor and the concrete component of the wall are both 0.5 feet which is 6 inches. The volume is 13879 x 0.5 = 6939.5 cu. ft. 18
2:00 PM 78
4
230.4
911.4 2703.4
12.5
4.9
3:00 PM 80
6
345.6
1367
18.8
7.4
4055
4:00 PM 82
8
460.8 1822.7 5406.7
25.1
9.8
5:00 PM 80
6
345.6
1367
4055
18.8
7.4
6:00 PM 78
4
230.4
911.4 2703.4
12.5
4.9
7:00 PM 77
3
172.8
683.5 2027.5
9.4
3.7
8:00 PM 76
2
115.2
455.7 1351.7
6.3
2.5
9:00 PM 75
1
57.6
227.8
675.8
3.1
1.2
10:00 PM 73
-1
0
0
0
0
0
11:00 PM 72
-2
0
0
0
0
0
12:00 AM 71
-3
0
0
0
0
0
1:00 AM 70
-4
0
0
0
0
0
2:00 AM 68
-6
0
0
0
0
0
3:00 AM 66
-8
0
0
0
0
0
4:00 AM 65
-9
0
0
0
0
0
5:00 AM 64 -10
0
0
0
0
0
6:00 AM 65
-9
0
0
0
0
0
7:00 AM 66
-8
0
0
0
0
0
8430 25006
115.9
45.5
Total
8524.8
Sum of loIr floor
From the calculation, it shows the total Heat Gain for 24 hours is 16,493.4 + 2.246,783 + 50,656 + 42,122.2 = 2,356,054.6 BTU From the Table 8.15 (page 298, MEEB), I know I-P (density x specific heat) is 22.5 BTU/°F Mass heat capacity = Mass volume x Density x Specific Heat = 6939.5 x 22.5 = 156,138.75 Btu/ft3°F
42122.2
During the daytime, the thermal mass only stores the heat. As it shows in the Table 1, the temperature starts to drop after 6 pm until 5 am, which is the time the thermal mass start to cool down. Also, the temperature of the thermal mass will slightly drop. Cooling = (Previous hour Mass temp. - Outside temp.) x Mass surface area x Surface conductance Surface conductance of 1.0 Btu/h ft2 ºF (the answer are is in the chart below) Calculate the decreasing mass temperature: Decreasing mass temperature = Previous hour mass temp. – (Cooling in BTU/h / Mass heat capacity) The answers are in the chart below: Table 5. Cooling & Mass temp. calculation
19
Time
T
cooling
Mass Temparature
6:00 PM
78
No heat removed
78
7:00 PM
77
(78 – 77 ) x 13879 x 1 = 13,879
78 – 316415/156138.75 = 77.9
8:00 PM
76
77.9 – 76) x 13879 x 1 = 26,370.1
77.9 – 26370.1/156138.75 = 77.7
9:00 PM
75
(77.7 – 75) x 13879 x 1 = 37,473.3
77.7 – 37473.3/156138.75 = 77.6
10:00 PM
73
77.6 – 73) x 13879 x 1 = 63,843.4
77.4 – 63843.4/156138.75 = 76.9
11:00 PM
72
76.9 – 72) x 13879 x 1 = 68,007.1
76.9 – 68007.1/156138.75 = 76.4
12:00 AM
71
(76.4 – 71) x 13879 x 1 = 74,946.6
76.5 – 74946.6/156138.75 = 76
1:00 AM
70
(76 – 70) x 13879 x 1 = 83,274
76 – 83274/156138.75 = 75.4
2:00 AM
68
(75.4 – 68) x 13879 x 1 = 104,092.5
75.4 – 104092.5/156138.75 = 74.7
3:00 AM
66
(74.7 – 66) x 13879 x 1 = 122,135.2
74.7 – 122135.2/156138.75 = 73.9
4:00 AM
65
(73.9 – 65) x 13879 x 1 = 123,523.1
73.9 – 12523.1/156138.75 = 73.0
5:00 AM
64
(73.0 – 64) x 13879 x 1 = 124,911
73 – 124911/156138.75 = 72.2
From the Table 5, it shows the total mass cooling capacity 13,879 + 26,370.1 + 37,473.3 + 63,843.4 + 680,007.1 + 74,946.6 + 83,274 + 104,092.5 + 122,135.2 + 123,523.1 + 124911 = 1,454,455.3 BTU Final mass temperature is 72.2°F. It is 8.2°F higher than the lowest outside air temperature, so I need to add more thermal mass. However, in this lab, I just calculated the floor area as thermal mass. When I add the entire thermal mass together, it will be better. Compare to the heat gain from Table 2-4, which is 2,356,054.6 BTU; cooling potential is not adequate to capture the heat gain during the day. King Pavilion could perform more energy-friendly if it has more thermal mass. The floor in King Pavilion is relatively thin, which greatly ruduce the amount of thermal mass. Also, the thermal mass in interior partitions is more effective than external walls. Since King Pavilion doesn’t have much interior wall. The thermal mass only exists in the floor and the exterior wall, which also reduces the amount and efficiency of the thermal mass. Material is another reason causing the low thermal mass. The thermal mass accounted in King Pavilion is mainly concrete, which has a low specific heat. If the building is constructed with more wood elements, it could definitely improve the heat capacity.
Cooling Load & HVAC Duct Size Evaluation As it has been calculated above, the space needs the active system to keep a comfortable interior environment. The first step is to figure the cooling load the space. Usually there are about 200 users in the building on both floors. The regular daily activities will be same as listed in the Thermal Mass section. Room condition desired: 70 F/ 50% RH Outdoor ventilation rate provided: 30 cfm/person Outdoor air condition: 80F / 75 F WB Table 6. Enthalpy Calculation
Heat Gains in the Room
Sensible Heat
Latent Heat
SH(BTU/H)
LH(BTU/H)
100x 250 (male)
77,760+ 25,000 +
513,520
100 x 200 (female)
20,000 = 122,760
The sum of other
31,200+ 690,841+
equipment as calculated
307,769+ 336,193 =
200 people working
sum Enthalpy of cooled air in
0
Room sensible
Room sensible
heat(RSH):
heat(RLH)
= 1,488,763 2,002,283
= 513,520
room Image 7. HVAC Duct
SHF (sensible heat factor) = RSH/ (RSH+RLH) = 1,488,763 / 2,002,283 = 0.74 Cfm = RSH/1.08 X ∆T = 1,488,763/ 1.08 x (80-70) = 137,848 cfm Quantity of incoming air: 200 x 40 cfm/ person = 8,000 cfm The function of the space is similar to large lecture hall, and the max RC should be 40. From the Image 7., the HAVC duct is round and suspended in the oppupiable space, From the Table 9.4 of the book Mechanical 20
and Electrical Equipment for buildings the max airflow should be 3900 fpm. The section of the duct, 8000 x 144 x 1/ 3900 = 295 sq in, so the radius should be 9.6 in According to my measurment, the duct in the King Pavilion has a radius of 12 in, so it should be adequate to conduct the air flow.
Acoustic Condition The acoustic condition is King Pavilion is not admirable as complained by many professors and students. On the first level, there is only one review space to be shared by the entire floor. As it is shown in the floor plan (image 3), the review space is open to the studio space on one side; the rest three sides are closed by two gypsum walls and one curtain window (image 9). The floor finishing is concrete. None of those finishing performs well in absorbing the sound. According to chart from the slides, I think the sound level on a normal day in the review space is about 55-70 decibels. In the noisier times, it is most likely ranging from 70 decibels to 80 decibels.
Image 8. King Pavilion Review Space
Window wall
Gypsum Wall
Gypsum Wall
Image 9. Detail Plan of the review space
Image 10. Noise level reference
From the book Mechanical and Electrical Equipment for Buildings, it is not hard to figure out that the review space has a desired reverberation time of 0.55 sec. In order to demonstrate if the acoustic condition of the review space is desirable, I have run the calculation as follows. Sound absorption coefficient a. Gypsum board ½” nailed to 2x4’s 16in: 0.08 b. Concrete floor finishing: 0.01 c. Sinlge layer glass window: 0.18 21
Total absorption = Area of the material x Sound absorption coefficient Gypsum wall: Total absorption = (15’ x 18’ x 2 + 30’x4’) x 0.08 = 52.8 sabins Single layer glass window: Total absorption = 30’x11’ x 0.18 = 59.4 sabins Concrete floor finishing: Total absorption = 18’x 30’ x 0.01 = 5.4 sabins Total sabins: 54.4+69.3+6.3 = 117.6 sabins From the original design, I found that not having a ceiling is the biggest problem for the review space. Also, concrete floor is not a good sound absorption material. To improve the studio area, I suggest adding a ceiling covered with fiber board. Then, I figured out that fiber board does a much better job at absorbing sound than gypsum board, so I propose to cover the entire gypsum wall with fiber board. Considering people using the review space as a working place in the regular time, I don’t think it is a good idea to replace the concrete floor. Because of a lot of messy types of media, it produces a huge amount of trash every day so concrete is ideal since it is easier to clean than carpet is.
Conclusion As the first LEED Platinum university building in the nation with limited budget, King Pavilion had surmounted many limits, especially in the natural light usage. Although the building still has many problems like acoustic issue and shading devices, it could be fairly easily renovated with extra budget. In terms of the evaluation process, the calculations and analysis has reached the initial plans.
22
Reference 1. Climate Consultant, version5.1 2. Walter T. Grondzik, Alison G. Kwok, Benjamin Stein and John S. Reynolds, Mechanical and Electrical Equipment for buildings- 11th edition, John Wiley & Sons. Inc, Portland, OR, 2010. 3. Norbert Lechner. Heating, Cooling, Lighting: Sustainable Design Methods for Architects, John Wiley&Sons Inc., Hoboken, New Jersey 4. Ulrike Passe, Building and Science Techonology Course Seris- Arch 341, 342, 343, 445. Architecture Department, Iowa State University. Ames, IA 5. Iowa State University Foundation, Ames, IA http://www.foundation.iastate.edu/s/1463/index_3col.aspx?sid=1463&gid=1&pgid=1261 6. U.S. EDepartment of Energy https://buildingdata.energy.gov/project/king-pavilion 7. RDG Planning & Design http://www.rdgusa.com/projects/iowa-state-university-college-of-design-king-pavilion 7. RDG Planning & Design http://www.rdgusa.com/projects/iowa-state-university-college-of-design-king-pavilion
23
The Building Envelope Failure of Western Berlin Congress Hall Author: Tianyu Feng Professor: Patrick Rhodes Date: Spring, 2013
Background The Congress Hall (image 1) was the American contribution to the International Building Exhibition in 1957. Today, it is called the Pregnant Oyster due to its thin shell concrete roof form. The thickness of the roof is measured at 3cm (about 1inch) on the top portion and 3 inches on the bottom portion. The steel tendons, embedded in thin reinforced concrete slabs for protection, were anchored under tension in the arches and central tension ring. Above a 92 by 96 meters base story raises the wide sweep of the roof structure. The roof is supported by steel anchors and only rest on the base with two points. The base story is generously glazed on both sides and comprises three staggered levels with a large reception hall, a cafeteria, a theatre auditorium with 400 seats, an exhibition area, further smaller rooms for congresses, seminars and the administration and, on the side facing the spree, a two-story restaurant. The hall itself contains the 1250-seats auditorium. Because of the almost round floor plan, the stage at one side is comparatively wide and shallow, and the rising rows of seats for the audience become increasingly wide. Initially, the original building envelope failed due to concrete creep, temperature stresses, rain, snow, settlement and other factors caused high fluctuating stress in the tensioning steel. Humanity and carbon dioxide were able to penetrate through the cracks to the tensioning steel, causing the severe corrosion and a gradual break of wires. Eventually, the stresses over the 23-year life of structure cracked the roof (Image 2 and Image 3). Later the building was reconstructed in 1989 with attention to a structure’s joint system and its fittings of pre-stressing tendons as well as the tendons themselves.
Image 2. Failure on structure
Image 1. Original The Congress Hall Image 3. Failure on Facade
Experiment description and goal My goal in examining the Congress Hall was to determine an affordable, efficient, and aesthetically pleasing solution to the failure of the building envelope (image7-10). To examine it and explore the reason of the failure, I create a scale model of the building envelope out of plaster. The plaster mold will 24
act as a testing platform to examine a variety of possible solutions to prevent water penetration and movement of the roof. I test four different types of roofing solutions. After testing, I will use the data collected to determine the best possible solution for redesigning the thin shell. Next, we will create two models. The first model will show the original design of the building envelope. The second model will be of our proposed solution for Congress Hall. Both models will be full-scale details. Each model will be able to be dismantled so that the layers can be examined individually or as a whole.
Solution According to the observations and analysis I made, there are three different possibilities for building envelope failure. The first potential failure is the installation of the building envelop. In the original design, the building installation was constructed in panels, which led to the higher possibility of water seeping through the seams of the panels. Based off our experiment, the solution of this possible cause would be adding a layer of shingles, which would be the best approach to diverging water. Glass shingles are one of the best choices. It is see-through so it has minimal influence on the aesthetics of the roof. We came to glass shingles as an optimal building cover after testing three other building envelope skins. The first skin we tried was to try to optimize the shape of the shell structure by only using the shell for water protection (Image 4). Because the structure had low points, water could easily build and eventually seep through. Our new shell design eliminated the two flat areas without changing the original form too much. The second solution (Image 5) we tried was to use metal channels to guide the water away from the flat areas. By channeling the water, very little water came in contact with the flat areas, eliminating standing water. The third solution we tried (Image 6 & 7) was the glass shingles. The shingles fit to the contours of the existing shell and more easily moved water off of the roof.
Image 4. Trial one
25
Image 6. Trial Three
Image 5. Trial Two
Image 7. Trial Four
Ultimately, the glass shingles were our most plausible solution because they disrupted the original design the least and were the most efficient at keeping the shell structure dry. The second potential failure is the concrete mixture on the exterior layer. The mixture of concrete panel was a porous concrete mix. Water can easily penetrate through the concrete layer and reach the water proof membrane. Also, the thickness of concrete panel is a big problem. When it was originally built in the 1960s, the techniques for concrete pouring were still immature. It’s extremely difficult to build a huge 3cm thick concrete panel with curved shape. The cracks could be caused by a gentle asymmetrical live load, which would have caused water penetration eventually. Nowadays, with more innovative and modern concrete mixtures, we are able to build a stiffer and more water-resistant structure. The third potential failure is the penetration of the waterproof membrane. The waterproof membrane is made of a special type of paper, which is fragile. It can be easily punctured during installation. Even heavy rain could tear up and penetrate through the membrane after the concrete layer was cracked. Using a seamless pour of concrete or tar could easily protect the water membrane.
Image 8. Original assembly of the roof
Image 9. Proposed assembly of the roof
Image 10. Original assembly of the roof
Image 11. Proposed assembly of the roof
Outcomes and conclusions By testing various roofing elements, I got the conclusion that using a completely poured in place roof with glass shingles will prevent the most water from penetrating the building envelope. The poured in place roof eliminates the joints that the original roof had due to being panelized. The glass shingles add additional protection and prevent the buildup of water in the flatter regions. The glass shingles also add a unique aesthetic to the building envelope with gives the roof the appearance of having feathers.
26
Reference 1. Galinsky http://www.galinsky.com/buildings/congress/ 2. Jacob Feld&Kenneth L. Carper, Construction Failure, 2nd Edition, Page 320-324, Wiley-Interscience, New York NY, 1996 3. Steffen de Rudder, Hugh Stubbins: Fifties American Modernism in Berlin, Jovis, Berlin Germany, 2007 4. The Atlantic Times http://www.atlantic-times.com/archive_detail.php?recordID=992
27
Tianyu Feng
LEED Green Associate
Email: tyfengpro@gmail.com tianyu.feng@ryerson.ca Phone: 1+416-956-8647 Address: 33 Bay Street, Unit 302, Toronto, Ontario, M5J 2Z3