Bridging Documents.pdf

U.S. Department of Health and Human Services Supply and Service Center

Building 14 Perry Point, MD 21902

T: 410.562.2244 F: 410.642.2047

HSS SUPPLY SERVICE CENTER, COLD STORAGE ADDITION

ENGINEERING/ARCHITECTURAL ANALYSIS

September 14, 2011

Prepared by:

Atlantic Design Group, Inc.

8940-F Route 108 Columbia, MD 21045 P: 410.884.9610 F: 410.884.9631 www.adesigngroup.com

HHS – COLD STORAGE ADDITION ENGINEERING/ARCHITECTURAL ANALYSIS

NORTHEAST, MD 14 SEPTEMBER 2011

ATLANTIC DESIGN GROUP, INC 0

ENGINEERING/ARCHITECTURAL ANALYSIS

HHS SUPPLY SERVICE CENTER

COLD STORAGE ADDITON

NORTHEAST, MD

TABLE OF CONTENTS

1 Executive Summary 1

2 Leased Warehouse Site 2

2.1 Floor Plan 3

3 Structural Analysis 3

4 Schematic Layout 3

4.1 Code Compliance Issues 4

5 Mechanical Analysis 6

6 Electrical Analysis 7

6.2 Proposed Source of Power for Cold Storage Facility 7

6.3 Approximate Electrical Load Addition 8

6.4 Generator 8

6.5 Fire Alarm 9

6.6 Refrigeration Alarm 9

6.7 Lighting 9

ATLANTIC DESIGN GROUP, INC 1

1 Executive Summary As Part II for the Cold Storage Addition Deliverables, the following document provides the Engineering and Architectural Analysis. The purpose is to evaluate the engineering and architectural features, concepts and challenges endured for the selected site. After consideration of the three possibilities, Site 1 from the Alternatives Analysis was selected.

Site 1 was surveyed and a geotechnical investigation was performed. The geotechnical investigation last revealed that the proposed building site has trash fill (building debris, pipe, wood, abandoned foundations) to a depth of 7’ to 9’ below ground surface. It appears from discussions with on-site personnel that this area was the location of a sulfate storage building. ADG’s geotechnical engineer proposed two foundation recommendations: One, remove the uncontrolled trash fill and replace with controlled engineered fill and then place conventional foundations and slab-on-grade; two, utilize micro-piles and a structural slab to avoid soil removal. Given the sites previous history as a energetics plant, ADG recommended an environmental investigation to characterize the material and sampling the ground water for contamination to determine if the soils can be removed with no remediation. The Geotechnical Investigation and Site Survey can be found in the Appendix

Presented with these findings, the government to construct the cold storage building inside an existing leased warehouse in Northeast, MD. The subsequent document provides an engineering and architectural analysis of this space and takes the following into consideration:

• Schematic Layout of the cold room with pallet rack spacing, necessary aisle spacing for material handling equipment, locations for doors and location of support steel

• Approximate mechanical (HVAC) sizing

• Approximate electrical load addition

• Existing building electrical service

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2 Leased Warehouse Site The cold storage facility will be located in an existing leased warehouse facility at 4 Center Drive in North East, Maryland. HHS currently leases approximately 85,000 SF. A building permit will be required for this construction.

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2.1 Floor Plan

3 Structural Analysis The original scope was to analyze Building 5 at Perry Point to determine effects of the addition on the existing structure. This was started but the decision to move the facility to Northeast suspended the effort on Building 5.

The leased warehouse facility is a steel framed highbay structure on spread footings with a slab-on-grade floor designed for heavy forklift traffic and highbay racking. The loads imposed by the proposed cold storage addition are minor compared to the designed loading capacity.

4 Schematic Layout The schematic layout proposes a 40’-8”’ wide by 44’-2” deep by 24-6”’ high (interior dimension) cold storage unit. This is approximately 1,800 square feet of usable floor space. Support steel is shown in approximate locations along the exterior walls and down the center of the cold storage unit. Structural bracing is proposed along two of the exterior walls.

The interior layout of the cold storage unit is based on the following:

• Pallets: 40” wide by 48” deep and 54” high

Approximate location of cold storage facility

Current leased area

Approximate location of generator/condensers

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• Material Handling Equipment: Forklift

This layout provides a total of 152 rack positions, when stacked 4 positions high. 4 rack positions are omitted for each pass through between the aisles; only the top two pallet positions are usable at these locations. Each pallet rack beam is 96” wide with 42” deep (48” deep including pallet) by 18’ high frame uprights. These dimensions create 8 rack positions when stacked 4 pallets high. Pallet racks are positioned 12” off the exterior walls and 12” apart where back to back to allow for the structure. There are two 10’-6” wide clear aisles. See the schematic layout and interior elevations for more details.

The main doors into the cold storage unit lead to the warehouse. A sliding entry door is proposed for forklift access. A man door on the north side of the cold storage unit is proposed as well. It will have exit hardware only with an alarm tied into the existing security system. If the door is opened, proper authorities will be alerted. No hardware will be provided on the exterior of the door for security purposes.

4.1 Code Compliance Issues

Although the existing building is not required to comply with current codes, alterations to that building are required to comply with requirements for new construction. Adding the cold storage unit into the warehouse is considered an alteration by the code and should be straightforward in terms of compliance.

These are our preliminary findings. However, it is the responsibility of the design/build contractor to provide a complete life safety and code analysis. The following is taken from IBC 2009.

• Use: Storage S-1, for pharmaceutical and medical surge supplies. No separation is required between the same occupancy.

• Construction Type:

• The new cold storage addition is Type 2B. (Steel framing on concrete slab with insulated metal panels for the walls). The existing building type is unknown, but appears to be Type 1 or 2 construction. It is constructed primarily of steel columns, with concrete exterior walls, concrete floors, and exposed metal roof decking.

• Height and Area Limitations: The existing building is 1 story and 345,756 square feet. The cold storage unit isn’t adding any square footage to the existing building; therefore, height and area limitations are not impacted.

• Fire Protection: The existing building is currently sprinklered. Sprinklers shall be extended to the cold storage facility.

• Egress: The cold storage unit must provide egress to meet current codes.

a. Egress is allowed through an intervening space (the warehouse) per Section 1014.2.

b. Number of Means of Egress: 1 required, 2 provided from the cold storage unit.

The occupant load of the cold storage unit is approximately 4. (Warehouses must provide 500 gross sf max per occupant; therefore, an 1800 sf cold storage unit has an occupant load of 4.) Per Table 1015.1 one means of egress is allowed in a Group S use with an occupant load of less than 29.

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c. Egress Width Factors: The proposed 8’ wide sliding door and 3’ wide man door will provide more than enough egress capacity from the cold storage unit. Once out of the cold storage unit, the existing exit doors, which are spaced at regular intervals, shall be used for egress.

Per section 3404.6, alterations to an existing building shall not be affected by the egress width factors of the code for determining the minimum egress widths and minimum number of exits from an existing building. This means that as long as the cold storage unit is positioned within the warehouse so that travel distances are not exceeded, the existing exits will be sufficient to comply with egress code requirements.

d. Exit Access: In a sprinkered building, Group S use the following is required.

Max Travel Distance: 250’ Max Common Path of Travel: 100’ Max Dead Ends: 50’

The proposed cold storage layout complies, and if the unit is positioned inside the warehouse as discussed, it should comply with the exit access requirements as well.

• Accessibility: The cold storage addition is not required to be accessible per 103.2.15.

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5 Mechanical Analysis The cold storage space shall be provided with multiple split systems, consisting of indoor coolers & outdoor air-cooled condensing units. The cooling load was approximated to be 10-tons. The design/build contractor shall verify final requirements. At a minimum, the space shall be provided with two (2), equally sized split systems to provide full “N + 1” redundancy during the situation of one (1) system undergoing routine service or failing to provide cooling due to indoor or outdoor unit operation. Optionally three (3) equally sized split systems, sized between 50% to 60% of the total load, can be provided to serve the space.

Providing the additional third unit would provide for greater “part load” control of the cold storage unit, however the logistics of installing three (3) indoor coolers within the space must be closely coordinated.

Insulated cooling condensate piping from the drain pans of indoor evaporators shall be provided – final destination within the warehouse shall be coordinated with HHS, but will need to be pumped to the discharge point.

This cooling tonnage is based upon the following assumptions:

(1) Room dimensions of 44’-0” long x 40’-0” wide x 25’-0” high.

(2) Room temperature set point of 40°F DB @ 90% relative humidity.

(3) Insulated wall & roof panels, with a minimum insulation value of R-30.

(4) Concrete floor slab, 0’-6” thick, assumed un-insulated.

(5) Infiltration caused by a single, 8’-0” x 8’-0” normally operating door, opening/quick closing twice per hour, into an existing warehouse, currently provided with heating & ventilation only.

(6) Miscellaneous heating load of forklift operation, overhead lighting, occupancy, and reintroduction of warmer dehumidification air into the conditioned space.

The cold storage space shall be provided with a desiccant dehumidification unit to control relative humidity to a maximum of 55%. The dehumidification load was approximated to be 600 CFM – contractor shall verify final requirements. The proposed system shall include, at a minimum, process booster fan & motor, reactivation fan & motor, electric reactivation heat source, 30% inlet filters.

The HVAC system shall be provided with controls able to equalize run time on the systems, as well as automatic switchover to the “lag” system when the “lead” de-activates. The HVAC controls shall be capable of maintaining an indoor temperature set point range of 36°F DB - 46°F DB. Deviations beyond this range are unacceptable. High and low temperature alarms shall be provided and coordinated with the User. The design shall include thorough temperature mapping within the entirety of the cold storage space to alert for necessary adjustments to provide for uniform temperatures throughout the cold room. Contractor shall coordinate all contacts (connected to a light, a buzzer, a bell etc.) for use in signaling an alarm with the User.

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6 Electrical Analysis The proposed location for the potential cold storage unit is ideal for the electrical systems. The space is served with 1600 Amp 480 three phase service.

6.2 Proposed Source of Power for Cold Storage Facility

The 1600 service feeds Distribution Panels within 120 feet of the proposed cold storage facility location.

There is spare spaces in these panels to serve the cold storage facility.

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6.3 Approximate Electrical Load Addition

The following are approximate load estimates for equipment, which will be located within the addition.

Load Voltage Estimated Load (A) Estimated Load (kVA) VA/SF Total kVA HVAC (Cooling) 480V 36 29.9

65.8 85.5 HVAC - Humidifier 480V 62 51.5

Lighting 277V, 120V 5.5A @277V, 12.5A @120V 2.6 Receptacles 120V 7 1.5

6.4 Generator

A dedicated generator strictly used for the cold storage facility shall be provided.

As discussed above, the power will be obtained from the existing distribution panels and will feed a 125A, ATS (automatic transfer switch). The ATS will connect the generator and the 480/277V panel for cooling equipment for continuous power upon power loss.

It is estimated a 70kW, propane generator will be needed in order to power the cooling equipment in the addition. The propane will come from the existing propane distribution piping on-site. D/B contractor to coordinate service with the building owner.

Generator/Condensing Units to be located outside of egress doors

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Propane distribution and storage

6.5 Fire Alarm

Fire Alarm is required for the proposed cold storage unit. Fire alarm devises can be fed from the existing fire alarm panel if adequate space is available.

6.6 Refrigeration Alarm

A temperature/humidity monitoring and alarm system for the proposed cold storage unit will be required and located within the building.

6.7 Lighting

A lighting level of 50 foot-candles at floor level shall be provided for this facility. T5, high-output, 54W lamps shall be used in reaching the 50 foot-candle level. The fixtures will also need to be rated for cold temperature environments.

The lights may be powered from the 480/277V panel or the 208/120V panel.

For energy efficiency, occupancy sensors shall be located in the cold storage facility and LED exit signs for emergency exit. Emergency lighting shall also be provided throughout the space via battery power. A minimum of 0.1 foot-candles is required at floor level with emergency lighting per NEC 2011.