boston architectural thesis part 2

DESIGNDEVELOPMENT

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OPTION A: FULL VIEW THRU VOID

OPTION B: MINIMIZED VIEW AT CENTER

V O I D R A T I O N A L E

Based on the feedback that I received at the last review, the first major decision I made was to create a major opening straight through the building that would then create a clear connection between Cambridge and Congress Street and offer users a place to gather or occupy.

This central intervention would serve as the focal point of the building, inviting users and visitors into the building during peak hours and also providing a more direct access from one end of the site to the other even during off hours.

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INTEGRATION OF USERSINTERVENTIONTHAT WILL ALLOW FOR

VOID AS CONNECTORUSERS: LOCALS + TOURISTSSYSTEMS: DIGITAL + ANALOGSTREETS: CAMBRIDGE + CONGRESS

CENTRAL INTERACTION BETWEEN SYSTEMS AND USERS

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LONGITUDINAL SECTION

R E V I S I O N S T O T H E C E N T R A L S P A C E

H U B REVISIONSBE MORE BOLDREDUCE SQUARE FOOTAGEOPEN UP ENTRIESGIVE VIEWS INTO BUILDINGCREATE PLACE THAT CATERS TO MULTIPLE INTERESTS AND USER TYPES

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A V I E W I N

VIEW OF DIGITAL/ANALOG WALL RAMP SYSTEM

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V I E W F R O M T H E M A I N R A M P

VIEW FROM TYPE OF MAIN RAMP

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CROSS SECTION

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3

2

1

F U R T H E R R E V I S I O N S T O B U I L D I N G L A Y O U T

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7

6

5

4

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P R O P O S E D U S E O F C E N T R A L S P A C E

VIEW FROM GOVERNMENT CENTER PLAZA

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STRUCTURALDESIGN

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G R O U N D F L O O R : C I T Y H A L L E X I S T I N G

ELEVATORSSTAIRSTEL/DATAPLUMBINGELECTRICALDUCTSESCALATORS

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G R O U N D F L O O R : C I T Y H A L L I N T E R V E N T I O N

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2 N D F L O O R : C I T Y H A L L E X I S T I N G


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2 N D F L O O R : C I T Y H A L L I N T E R V E N T I O N

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3 R D F L O O R : C I T Y H A L L E X I S T I N G


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3 R D F L O O R : C I T Y H A L L I N T E R V E N T I O N

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4 T H F L O O R : C I T Y H A L L E X I S T I N G


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4 T H F L O O R : C I T Y H A L L I N T E R V E N T I O N

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W O R K I N G W I T H T H E G R I DT

H E

R A

M P

S Y

S T

E M

PERSPECTIVE SECTION FROM GOVERNMENT CENTER

CONCEPTUAL DIAGRAM OF RAMP SYSTEM HANGING FROM CABLES TO TRUSSES FOR STRUCTURAL SUPPORT

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A V I E W I N

STRUCTURAL DETAIL MODEL

EXPOSING EXISTING CITY HALL GRID SYSTEM

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MECHANICAL:

Creating such a large void in the center of the building left very few areas to create vertical shafts for my mechanical systems and circulation. I thus decided to downsize the existing shafts on the analog (pink) end and mirror a new set of shafts on the digital (blue) end.

Additionally, because the central ramp traverses the vertical distance of two floors, I used the space below the ramp to store my heating and cooling units that then would extend out to both ends and travel up the through the shafts on the ends of the building.

M E C H A N I C A L S Y S T E M

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S T R U C T U R A L S Y S T E M

MECHANICAL SYSTEMS DIAGRAM

STRUCTURAL SYSTEMS DIAGRAM

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G E T T I N G I N T O T H E S P E C I F I C S

WALL SECTION

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ROOF DETAIL

CURTAIN WALL DETAIL

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REVIEW FEEDBACKThis was by far the most difficult review for me. Because my work experience to date rarely deals with figuring out these types of systems, I relied heavily on the input from my structural and mechanical advisors - Amir Mesgar and Bruce MacRitchie.

The fact that I was removing such a large amount of the center of an existing concrete struc-ture like City Hall meant that I had to resolve a lot of issues structurally. By spanning 6-foot deep S T E E L T R U S S E S across the top of the roof and also creating a canopy similar to the roof, I was able to accomplish such a feat. While the depth of the trusses initially seemed problematic, with a building of this scale it proved to not be as much of an issue as I had originally anticipated since I ultimately decided to cover the trusses with W O O D P L A N K V E N E E R below and D I G I T A L P A N E L S across to help with wayfinding, navigation and signage.

The reviewers seemed to agree with the decisions I had made and liked the idea of covering the structural system to help key users into the happenings of the building since the existing conditions of the site and the building do anything but give passersby any sort of easy visual or physical access.

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FINALREVIEW

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VIEW FROM GOVERNMENT CENTER PLAZA

F I N A L M O D E L

VIEW FROM CONGRESS STREET

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VIEW FROM JFK BUILDING

AERIAL VIEW FROM CAMBRIDGE STREET

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D I G I T A L E N D P E R S P E C T I V E S

COMPUTER LAB

FILM SCREENING ROOMLAPTOP HUB

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A N A L O G E N D P E R S P E C T I V E S

CHILDREN’S READING ROOM

BOOK STACKS SECTION

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T W O E N D S C O M I N G T O G E T H E R

BOOK STACKS SECTIONCOMPUTER LAB

COMMUNAL STUDY SPACE

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G R O U N D F L O O R : F I N A L

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2 N D F L O O R : F I N A L

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3 R D F L O O R : F I N A L

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4 T H F L O O R : F I N A L

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A L O O K I N T O T H E V O I D

CLOSE UP VIEW OF CENTRAL VOID

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T H E C E N T R A L S P A C E

VIEW OF CENTRAL RAMP FROM UPPER FLOOR

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C E N T R A L I N T E R V E N T I ON

S E C T I O N A L V I E W S

AERIAL VIEW OF FINAL MODEL

CROSS SECTION ALONG CENTRAL RAMP

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AERIAL VIEW OF FINAL MODEL FROM CONGRESS STREET

SECTION SHOWING CENTRAL INTERVENTION

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C I R C U L A T I O N O F S P A C E

CIRCULATION OF SPACE + LIFE SAFETY SLOPES

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F I N A L P R E S E N T A T I O N B O A R D

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REVIEW FEEDBACKHaving kept with the same reviewers throughout the entire year, it was helpful to get feedback based on a knowledge of an entire year’s worth of progress and revisions.

Most of the feedback from this final review was that M O R E P E R S P E C T I V E S in and around the exterior of the building would give viewers an even better idea of the building and its concept but they appreciated the C O N S I S T E N C Y of the project, the graphics and the work.

With the current conditions of City Hall being that it is visually impenetrable and hard to access, the decision to cut a void through the center of the brutalist building seemed to offer a G O O D R E L I E F and solution to how to better E N G A G E the building with potential users and the surrounding site.

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APPENDIX

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M E A N S O F E G R E S S + F I R E R A T I N G S

2ND FLOOR MEANS OF EGRESS

*2-hr fire-rated walls to line the perimeter of all stairwells and vertical shafts.

The remainder of the building to be 1-hr fire-rated walls.

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IGHT

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- 4"

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- 10

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"

T.O

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ING

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IT7'

- 4

1/2"

CLEAR SPACE BETWEEN STACKS3' - 6"

STACKS ON CENTER5' - 6"

DISTANCE BETWEEN SPRINKLER HEADS15' - 0"

TYP.

TO

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OF

SPRI

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9' -

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MIN

. ALL

OW

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1/2

"

DUCTS ON CENTER13' - 0"

SCALE: 3/8" = 1'-0"1 ADA STACKS

LF subtotalSFS DFS SFS DFS

linear feet per shelf 21 42 9 18Seventh FloorLF subtotal

Sixth FloorLF Subtotal

Fifth Floor 216LF Subtotal 9072 9072

Fourth Floor 71 228 20 20LF Subtotal 1491 9576 180 360 11607

Third Floor 15 30 30LF Subtotal 315 1260 270 1845

Second Floor 91 158LF Subtotal 1911 6636 8547

Ground Floor 84 10 15LF Subtotal 3528 90 270 3888

3495910

34959085%

297152

250000

547152

ideal capacity

VOLUME SUBTOTAL

Compact Storage

VOLUME GRAND TOTAL

7H 3H

TOTALbooks per linear foot

VOLUME TOTAL

T H E S T A C K S

LIBRARY VOLUME COUNT

ACCESSIBILITY THROUGH STACKS

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S U S T A I N A B I L I T Y

Buildings constructed from robust materials that withstand time serve as prime candidates fore building resuse. Buildings like Boston City Hall, constructed from precast concrete, fit this criteria perfectly.

Adaptability is a key factor underlying the ultimate service life of a building. The design intervention for the HUB may have eliminated a large chunk of the central core of the existing structure, but the rest of the building remains untouched, especially within the interior conditions of the space.

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S O I L S + D R A I N A G E

The existing site is known for its weak soil condition, hence the application of piles and pile caps in the

foundation. Additionally, the tunnels and train system below make the area more susceptible to vibration.

In terms of drainage, runoff will follow along the angle of the ramps on site, collecting at the edge of Congress

Street, where the existing drainage system is located.

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C O D E S R E P O R T

Project: New Boston Public Library

APPLICABLE CODES/REGULATIONS: Massachusetts State Building Code, 780 CMR, 8th Edition International Building Code, 2009 Edition Massachusetts Architectural Access Board (MAAB) 521 CMRADA Accessibility Guidelines City of Boston, Boston Redevelopment Authority - Zoning Ordinance

CODE SUMMARY INCLUDES:

Zoning Compliance Occupancy Classification General Code InformationHeight & Area Limitations Fire Resistance Ratings Fire Protection Systems Means of Egress Accessibility Plumbing Fixtures Interior Finish Classifications

ZONING COMPLIANCE

Site: CITY HALL PLAZA Lot Area: 479, 160 SF (11 acres)Frontage: None designated per BRA, due to Open Space DesignationSetbacks: None designated per BRA, due to Open Space Designation

Zoning Designation: Open Space, Public Ownership Government Center/Markets District (Urban Plaza Open Space Sub-district) (Urban Renewal Area Overlay District)

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Construction Type: Type IA – Fire-Resistive (Chapter 6) 3 Hour Structural Frame 3 Hour Exterior Walls

2 Hour Floor/Ceiling Assembly 1 1/2 Hour Roof Protection

Primary Use Group: B, A-3 Height & Area Allowed: UL (Table 503) Height Restriction: 125/ 155’ (Section 45-7) (Boston Redevelopment Authority) Floor Area Ratio (FAR): 8/10 (Section 45-7) (Boston Redevelopment Authority)

Floor Level GSF

Ground 46104

2 35565

3 41883

4 35612

5 35234

6 39126

7 54843

Total

288367

Boston Zoning Code, Volume II, Section 45-7: “City Hall Medium Density Area. Within that portion of the Government Center/Markets District depicted on Map 1H of the Code as the "City Hall Medium Density Area," a maximum building height of one hundred and twenty-five (125) feet and a maximum FAR of eight (8) are allowed, provided that any Proposed Project shall be allowed a maximum building height of one hundred and fifty-five (155) and a maximum FAR of ten (10) if such Proposed Project is subject to or has elected to comply with Large Project Review and has received a Certification of Compliance pursuant to Section 80B-6.”

Sprinkler System: Automatic Sprinkler System (NFPA 13) OCCUPANCY CLASSIFICATION Proposed Occupancy Classification: Mixed-use Building: B (business) (Section 304.1) A-1 (assembly) (Section 303.1)

A-2 (assembly, (Section 303.1) A-3 (assembly), separated (Section 303.1)

S-2 (low-hazard storage), incidental use (Section 311.1) M (mercantile) (Section 309.1)

GSF

Overall Site 479160

Zoning Poly 213081

Calculation

FAR 1.1

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GENERAL CODE INFORMATION New Building Systems: All new building systems are required to comply with the code requirements for new construction to the fullest extent applicable. Occupant Load: (780 CMR Section 1004.1.1) Ground Floor 49,589 GSF 1126 Occupants Floor One 31,455 GSF 674 Occupants Floor Two 31,455 GSF 549 Occupants Floor Three 31,455 GSF 549 Occupants Floor Four 31,455 GSF 549 Occupants Floor Five 21,207 GSF 424 Occupants Minimum Exits: (780 CMR Section 1010.2) Ground Floor 1126 Occupants 4 Exits Required 4 Exits Provided Floor One 674 Occupants 3 Exits Required 4 Exits Provided Floor Two 629 Occupants 2 Exits Required 2 Exits Provided Floor Three 629 Occupants 2 Exits Required 2 Exits Provided Floor Four 629 Occupants 2 Exits Required 2 Exits Provided Floor Five 424 Occupants 2 Exits Required 2 Exits Provided HEIGHT AND AREA LIMITATIONS The following proposed building use group configuration complies with Chapter 3, 4 5: Ground Floor Use Groups A-1, B, S-2, Floor One Use Groups A-3, B, M Floor Two Use Groups A-2, A-3, B Floor Three Use Groups A-2, A-3, B Floor Four Use Groups A-2, A-3, B Floor Five Use Groups A-3, B Height & Area Allowed:

B 5 floors, 37,500 GSF (Table 503) A-3 3 floors, 15,500 GSF (Table 503)

Proposed fire separation 2

nd, 3

rd, 4

th, and 5

th Floor Ceilings: The project will have interconnected smoke detectors; therefore, no fire rating of the

ceiling/floor assembly will be required (per Chapter 4). Automatic Sprinkler System Increase: (Section 506.3) Where a building is equipped throughout with an approved automatic sprinkler system in accordance with 780 CMR 903.3.1.1,the area limitation in Table 503 is permitted to be increased by an additional 200% for multistory buildings and an additional 300% for single-story buildings. These increases are permitted in addition to the height and story increases in accordance with 780 CMR 504.2.

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FIRE RESISTANCE RATINGS For Type IIA construction, the building elements listed in Table 601 are of noncombustible materials, except as permitted in Section 603. Ratings for Bldg. Elements Type IIA (Table 601) Structural Frame Incl. secondary members 1 hr Bearing Walls Exterior 1 hr (Table 602) Interior 1 hr Nonbearing Walls & Partitions Exterior 1hr Interior 0 hr Floor Construction Incl. secondary members 1 hr Roof Construction Incl. secondary members 1 hr Some incidental use areas are required to have fire ratings and/or a fire extinguishing system. Because the building will have an automatic sprinkler system per 780 CMR 903, fire rated separation assemblies will not be required for incidental use areas. Accessory use areas are not required to be separated with a fire rated barrier provided that it meets certain requirements. Incidental Use Areas (Table 302.1.1) Furnace Room (with 40,000 btu/hr) 1hr rating or auto fire extinguishing system Storage Rooms (over 100 GSF) 1hr rating or auto fire extinguishing system Incidental use areas: (Section 302.1.1) Spaces which are incidental to the main occupancy shall be separated or protected, or both, in accordance with Table 302.1.1 or the building shall be classified as a mixed occupancy and comply with 780 CMR 302.3. Areas incidental to the main occupancy shall be classified in accordance with the main occupancy of the portion of the building that the incidental-use area is located. Accessory Use Areas: (Section 302.1.2) A fire barrier shall be required to separate accessory use area classified as Group H in accordance with 780 CMR 302.3.2, and incidental use areas in accordance with 780 CMR 302.1.1. Any other accessory use area shall not be required to be separated by a fire barrier provided the accessory use area occupies an area not more than 10% of the area of the story in which it is located and does not exceed the tabular values in Table 503 for the allowable height or area for such use. Exterior Walls (Table 602) Fire Ratings for Ext. Walls Type IIA Fire Separation Distance Less than 5 ft 1 hr 5-10 ft 1 hr 10-30 ft 0 hr Over 30 ft. 0 hr Exterior Wall Openings There are limits to how many exterior wall openings when the exterior wall is within a certain distance of a lot line, the centerline of a street or between two buildings on the same lot. For buildings with a sprinkler system, the limits for protected openings can be applied to unprotected openings. Since this project will be fully sprinklered, there is no limit due to project’s setback from surrounding buildings. Fire Separation Distance – Degree of Opening Protection (Allowable %) (Table 705.8) Max. Area 0-3ft. 3-5ft 5-10ft 10-15ft 15-20ft 20-25ft 25-30ft over 30ft Unprotected, Sprinklered: NP 15% 25% 45% 75% no limit no limit no limit not req. Protected: NP 15% 25% 45% 75% no limit no limit no limit not req.

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FIRE PROTECTION SYSTEMS Automatic Sprinkler System The sprinkler system shall comply with 780 CMR 903. Zoning. Specific smoke detector zoning shall be in accordance with 780 CMR 907.0 with smoke detectors spacing no greater than 30 feet unless otherwise allowed via manufacturer’s listing requirements. MEANS OF EGRESS Occupant Load Library (Table 1004.1.1)

Reading Rooms 50 SF/occupant, net Stacks 100 SF/occupant, gross

Business Areas 100 SF/occupant, gross Assembly Concentrated 7 SF/occupant, net Standing space 5 SF/occupant, net Unconcentrated 15 SF/occupant, net Egress Width Min. egress width = 36” (with occupant load under 50 – typical for most spaces in this project) = 44” (with occupant load 50 or over) Because of the small occupant load, the minimum egress width dimension will be set by the standard minimum building code width, not per the width/occupant load table 1005.1 Maximum Door Encroachment = 22” during swing (½ of the required width) Corridor Width: For A-3 see 780 CMR 1024.0. (Section 1016.2) The minimum corridor width shall be as determined in 780 CMR 1005.1, but not less than 44 inches. Exceptions:

1. 24 inches – For access to and utilization of electrical, mechanical or plumbing systems or equipment. 2. 36 inches - With a required occupant capacity of 50 or less. 3. 36 inches - Within a dwelling unit. 4. 72 inches - In Group E with a corridor having a required capacity of 100 or more. 5. 72 inches - In corridors serving surgical Group I, health care centers for ambulatory patients receiving outpatient medical care, which causes the patient to be not capable of self-preservation. 6. 96 inches - In Group I-2 in areas where required for bed movement.

Common Path of Travel Maximum Length = 75 ft. Exceptions:

1. The length of a common path of egress travel in an occupancy in Groups B, F and S shall not be more than 100 feet provided that the building is equipped throughout with an automatic sprinkler system installed in accordance with 780 CMR 903.3.1.1. 2. Where a tenant space in an occupancy in Groups B, S and U has an occupant load of not more than 30, the length of a common path of egress travel shall not be more than 100 feet. 3. The length of a common path of egress travel in occupancies in Group I-3 shall not be more than100 feet.

Required number of exits Every floor area is required to have 2 exits (occupant load 500 and less). (Table 1018.1) Per the IBC 2003 commentary, this requirement applies to the space, not the occupancy of the floor/building. This interpretation should be confirmed with the Building Inspector.

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Length of Travel Max. length of exit access travel Without Sprinklers With Sprinklers (Table 1016.1) Use Group A 200 ft 250 ft Use Group B 200 ft 300 ft Dead Ends Max. length = 20 ft. (length is not limited when the dead-end corridor is less than 2 ½ times the least width) Door width = 36”, minimum ACCESSIBILITY Public Buildings ( MAAB 5.1) A building privately or publicly financed that is open to and used by the public, including but not limited to transportation terminals, institutional buildings, educational buildings, commercial buildings, buildings having places of assembly, hotels, motels, dormitories, multiple dwellings consisting of three or more units, 5% of the units in lodging or residential facilities for rent, hire or lease containing 20 or more units, public use and common use areas of apartment building and condominiums, parking lots of 15 or more automobiles, public sidewalks and ways, funeral homes, and public rest rooms, and public areas of shopping centers and restaurants. Entrances ( MAAB 25.1) All public entrances of a building shall be accessible. Public entrances are any entrances that are not solely service entrances, loading entrances, or entrances restricted to employee use only. All means of egress doors shall have a level space on both interior and exterior sides of the doors. The approach to an accessible entrance shall be a paved walk or ramp with a slip resistant surface, uninterrupted by steps. Entrance(s) shall have a level space on the interior and exterior of the entrance doors. Stairs All stairs are required to comply with 521 CMR requirements for tread/riser configuration and handrails. PLUMBING FIXTURE REQUIREMENTS

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the end.

INTERIOR FINISH CLASSIFICATIONS (Section 8) Flame Spread Index Smoke-Developed Index Class A 0-25 0-450 Class B 26-75 0-450 Class C 76-200 0-450 Required Pill Test per Consumer Safety Commission 16:

Occupancy Critical Radiant Flux Sprinklered

A, B, E, H, I-4, M, R, S Class II FF-1

804.4 Governs the interior floor finish in vertical exits , exit passageways, exit access corridors, and rooms not separated from exit access corridors by full-height partitions extending from the underside of the floor to the underside of the ceiling. The finishes in these conditions are to withstand a minimum critical radiant flux as specified in 804.1.1 Exception: Group A occupancy, when equipped with sprinklers, the amount of flame resistant decorative materials may not exceed 75% of the aggregate area of walls and ceiling per 806.1.2

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the end.

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boston architectural thesis part 2

Documents

i n t e r v e n t i

s i o n s t o t h e

s i o n s t o b u i

c i t y h

t h t h e g r i dt h

centerv o i d r

e w f r o

d i n g