Building Name:
77 K Street
Location and Site:
77 K Street, NE
Washington, District of Columbia 20001
The project site is located on the southwest corner of 1st and K Streets. This is four blocks north of Union Station, the primary train station servicing the District of Columbia. Additionally, the site is approximately one mile north of the nation’s capitol.
Building Occupant Name:
The tenant’s of the building will be determined at a later date.
Occupancy and Function Type:
77 K Street is primarily composed of typical floors approved for business occupancy. In addition, the first floor has mercantile and retail spaces available for rent with direct accessibility to street level.
Size:
The building sits on 32,314 SF and has a total square footage of 449,130 SF, including an underground parking garage.
Number of Stories Above Grade / Total Levels:
The building is 11 levels above grade and 14 total levels including the underground parking garage.
PRIMARY PROJECT TEAM
Owner: Brookfield Properties
Architect: Davis, Carter, Scott, Ltd.
General Contractor: James G. Davis Construction Corporation
Civil Engineer: Edwards & Kelcey, Inc.
Structural Engineer: Fernandez & Associates
MEP Engineer: Girard Engineering, PC
Dates of Construction:
Start – November 2006
Completion – September 2008
Cost of Construction:
$41,000,000
Project Delivery Method:
Design-Bid-Build
ARCHITECTURE
Design and Functional Components:
The 77 K Street base building project contains a variety of spaces including three levels of underground parking. The first floor contains a two-story lobby, retail space, an exercise facility, managerial offices, and a mailroom. The high-end lobby features honed granite floors, white Venetian plaster, wood veneer, and granite stone walls. Beginning at floor two, the building is designed for office tenants. The core of each floor contains the MEP rooms, elevator shafts, restrooms, and stairways.
The building was designed to reach its maximum height potential. It stands just shy of the 130’ limitation, created in the District of Columbia to prevent any building from standing taller than the nation’s capitol. The building also contains a rooftop terrace that provides views both east and south towards the Capitol Building, an appealing feature for the building’s future tenants.
Major National Model Codes:
International Building Code 2000
International Energy Conservation Code 2000
International Plumbing Code 2000
International Mechanical Code 2000
International Electrical Code 1996
International Fire Code 2000
ICC / ANSI A117.1
ADAAG (Americans with Disabilities Act Accessibility Guidelines)
Zoning:
77 K Street is zoned as type C-3-C under District of Columbia Title 11, Zoning 2002. C-3-C is a “high bulk major business and employment” zone. The code states that C-3-C “Permits matter-of-right development for major business and employment centers of medium/high density development, including office, retail, housing, and mixed uses to a maximum lot occupancy of 100%, a maximum FAR of 6.5 for residential and for other permitted uses, and a maximum height of ninety (90) feet.” Because 77 K Street sits in the NoMa Development District, north of Massachusetts Avenue, the owner was able to obtain a code variance to increase both the maximum FAR and the building height.
Historical Zoning Requirements:
77 K Street is 11 stories above grade measuring 129’-11-1/2” tall, a mere 1/2” below the Washington, DC height restriction of 130’.
Building Envelope:
The exterior façade is predominantly composed of architectural precast concrete panels with punched out windows. Behind the precast panels, which are mounted at each slab level, there are 2” to 3-5/8” light guage metal studs with R-13 batt insulation and either a single or double layer of 1/2” gypsum wallboard. The precast also has metal mullions attached to the outside to visually extend the lines of the windows both vertically and horizontally throughout the building.
At the entrances to the building on the north and east elevations, there are two story granite entries into the lobby. Proceeding up the building from these entranceways there are minimal amounts of precast but rather a façade predominantly composed of insulating vision glass windows, metal mullions, shadow boxes, and metal slab covers at the floor levels. The top two floors of the entire building have similar features. Elsewhere throughout the building façade, the eye is met for the most part by sets of two or three windows separated both above, below, and to the sides by light colored architectural precast.
The mechanical penthouse on the roof has an engineered insulating finish system mounted to structural steel which is not visible from street level.
The roofing system is composed of a hot fluid-applied roofing membrane directly above the concrete slab. Type VI rigid polystyrene insulation is placed above the roofing membrane. Finally, either a size 4 aggregate ballast ranging in size from 3/4” to 1-1/2” or two foot square roof pavers are placed above.
BUILDING SYSTEMS
Contractual Arrangements:
This project was developed via a design-bid-build delivery system. The ownership entity, 77 K Street LLC, sought to invest in a commercial development project in Washington, DC. After Davis, Carter, Scott developed a design the project was put out to bid. The initial general contractor selection was based on a negotiated contract but after the owner sought a lower cost bid, the project was put out for competitive bid to a group of three shortlisted contractors. The ultimate decision was based on a number of criteria including cost, schedule, contractor’s team, reputation, and qualifications with similar sized projects. Davis won the job in November 2006.
The owner-general contractor agreement is AIA A111, a cost plus fee contract with a guaranteed maximum price. The original guaranteed maximum price for the project was $41,005,150 with a stipulated, lump sum fee of approximately $1.4 million. Additionally, there are stipulations for liquidated damages starting at $1,000 per day for delays in substantial completion.
The owner-general contractor agreement requires that James G. Davis Construction Corporation obtain the following insurance policies: Worker’s Compensation, Employer Liability, Commercial General Liability, Automobile Liability, Umbrella Liability with a minimum limit of $50,000,000 per occurrence, Contractor’s Pollution Liability, Pollution Legal Liability, Professional Liability, and All Risk. Davis Construction does require most subcontractors that furnish and install work to be bonded.
Demolition and Excavation:
The project is being constructed on the lot of the former 65 K Street building. 65 K Street was a two story masonry building with a basement. The building sat on 16,486 SF at the northwest corner of the lot. A fifty-two car asphalt parking lot wrapped around the south and east sides of the building. Demolition of the existing building was not included in the scope of work for the 77 K Street contract. The removal of 65 K Street, the asphalt parking lot, select utility lines, and certain site features took place prior to the general contractor selection for the new building.
In order to support the excavation of the three level underground parking garage, a soldier beam, lagging, and tieback system was utilized. Testing by ECS Mid Atlantic estimated that groundwater would be found between 18 an 39 feet below site grade, thus a temporary dewatering system was installed during excavation and construction with a discharge on the southeast corner of the building on 1st street. Discharge rates in the range of 50 to 100 gallons per minute were to be expected and additional sump pumps were needed as excavation progressed. A permanent sump pump is to be installed in the building as well.
Structural System:
77 K Street utilizes a cast in place concrete structural system. The foundation is a 4’-0” thick, 4,000 psi concrete mat foundation resting on undisturbed soil with a minimum 4,000 psf bearing capacity. Below grade parking levels through the first floor are 9” reinforced concrete flat slabs with 5-1/2” drop panels at select column locations. Floors two through the roof are 10” or 11” post-tensioned two-way slabs with 4-1/4” drop panels at all columns and around the slab perimeter. The upper roof of the mechanical penthouse is framed using a combination of concrete and hollow structural steel members with a 8” one-way slab roof. Typical columns have a compressive strength of 5,000 psi with select columns having increased capacity up to 10,000 psi. Slab concrete capacities range from 3,000 psi at the lowest garage level to 5,000 psi for above grade slabs. Concrete is placed using two tower cranes, both staged within the footprint of the building.
Mechanical System:
In order to meet ventilation requirements, the three levels of underground garage parking each receive just over 49,000 CFMs of fresh air via intake and exhaust shafts and fans. Both the intake and exhaust shafts contain two propeller type fans at each garage level.
The first floor of 77 K Street contains two water cooled air conditioning units. One 7200 CFM unit supplies air to the lobby of the building with a smaller 1890 CFM unit controlling air quality within the fitness center. The base building project has mechanical rooms located in the core of each floor with the primary mechanical equipment located on the roof of the building. Three 91,560 CFM cooling tower units supply chilled air to the building. One outside air, gas fired supply unit provides 50,000 CFMs to the mechanical rooms on each floor level. Additionally, each floor contains a 27,000 CFM air conditioning unit for distribution to VAV boxes located in the tenant spaces. At this time, only a limited number of variable air volume units will be installed in order to provide temporary heat to the building’s tenant spaces. The majority of the VAV boxes will be stockpiled and installed during future tenant build out.
Stair pressurization shafts contain supply register diffusers at every second or third floor. Air volume at such diffusers is between 1250 and 1500. The top of stairwell two contains a 7500 CFM in line fan unit supplying outside air to the pressurization shaft. Stairwell one, which services only the above grade levels, contains a smaller 6000 CFM fan.
Plenum spaces range in size from 29” in the core of the building to 22” in the tenant spaces. Typical supply ducts are 16” in height and reduce to a 12”. Plenums in the tenant spaces also contain the recessed light fixtures, VAV units, and sprinkler pipes. They are concealed with two layers of gypsum drywall.
Fire Protection System:
The building is classified as a type 1-B structure and must adhere to the NFPA 13 standard for fire sprinklers. In order to reduce the fire risk to the building, above grade levels have a wet pipe fire suppression system, whereas the garage and loading dock areas have a typical dry pipe suppression system. A 6” incoming fire protection service is located on the P1 level. After passing through a double backflow preventer this service passes through a jockey and service pump to distribute water throughout the building, via two 1-1/2” standpipes with one located in each stairwell. The first level of the building contains a fire department siamese and pump test connection on the north elevation.
Electrical System:
77 K Street contains a standard 408/277V and 208/120V four wire, three phase electrical system. The main switchgear room, located on the P1 level, contains three 4000A switchboards and a single 2000A switchboard. Two of the 4000A switchboards power the normal operations of the building with the third dedicated to emergency systems. The 2000A switchboard is dedicated to the retail space on the first floor. A 750kW diesel powered generator located on the roof powers the emergency systems in case of a power outage. Power is distributed throughout the building by 4000A plug-in feeder busways and panelboards ranging in size from 150 to 400 amps.
Lighting System:
The lighting in the building is a combination of metal halide and fluorescent fixtures. The metal halide lighting systems are located predominantly in the garage levels and loading dock areas. The linear and compact fluorescents located in the core and tenant spaces. On the roof of the building there is an outdoor photocell facing north to control lighting levels within the building. Additionally, under consideration is the possibility of adding occupancy sensors with fifteen minute time-out delay settings to control lighting levels within the tenant spaces.
Transportation:
The building contains two stairwells providing means of egress. Stairwell one, located on the northern side of the building core, services the above grade levels, floors one through the penthouse. Stairwell two extends from the P3 level through the penthouse, though the location of the shaft shifts when the stairwell reaches grade level.
The building also contains nine elevators. Two elevators service the garage, one large service elevator services floors one through eleven, five typical passenger elevators service floors one though eleven, and one additional passenger elevator services floors one through the penthouse. The six passenger elevators located in the core of the building have a rated capacity of 4000 pounds, the service elevator has a capacity of 4500 pounds, and the two garage elevators have a smaller capacity of 3500 pounds. All elevators travel at a rate of 350 feet per minute.
Telecommunications:
The main telecommunications closet is located adjacent to the electrical room on the P1 level. Six 4” PVC coated galvanized rigid steel (GRS) conduits are provided for use by Verizon. Six 4” sleeves located behind the northern elevator shaft provide distribution throughout the floor slabs of the building. Infrastructure for card readers has been provided in both stairwells on floors two through eleven to provide secure access to the building’s tenants.
The main reception desk has direct access to various security and life safety features throughout the building. These include control of the loading dock and garage areas. They also have alerts regarding the operation of the emergency generator and the fire alarm annunciator panel.
