Green Village Program Narrative.pdf

SMITHSONIAN INSTITUTION

Green Village Cottages and Site Infrastructure

Smithsonian Environmental Research Center 647 Contees Wharf Road Edgewater, Maryland

Design Narrative and Program Requirements

SMITHSONIAN FACILITIES PROJECT NO. 1282111

March 17, 2021

TABLE OF CONTENTS

1.0 GENERAL PROGRAM REQUIREMENTS

2.0 SITE DEVELOPMENT

3.0 ARCHITECTURE

4.0 STRUCTURAL

5.0 MECHANICAL

6.0 PLUMBING

7.0 ELECTRICAL

8.0 LIFE SAFETY/FIRE PROTECTION

9.0

SECURITY

All material provided herein is for information only and is based on preliminary project planning. The Design-Build Team shall be responsible confirming and/or amending this information to develop a Basis of Design and subsequent construction documents that fully comply with all requirements of the project RFP, including Passive House Design and pre-fabricated modular design and construction.

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1.0 GENERAL PROGRAM REQUIREMENTS

1.1 GENERAL

The Green Village at the Smithsonian Environmental Research Center (SERC) in Edgewater, Maryland, will provide housing for visiting scientists. It will consist of six (6) cottages located on a sloping site north of the existing dormitory building. Future build-out of the

Green Village will also include a new 24 room new Lodge including a common kitchen area, eating area and gathering areas, as well as requisite utility areas.

This project provides for site improvements and utilities to facilitate the construction of all six (6) cottages, as well as the design and construction of the

Cottages themselves. Stub-ups are included for utilities to serve the future Lodge.

Existing Green Village structures include the Schmidt Center and Dormitory building, which will remain in place and fully operational during construction.

1.2 COTTAGES

Each cottage will be approximately 1,200 GSF, comprised of 2 bedrooms, 1 living room, 2 full bathrooms, a full kitchen and requisite utility areas. The first two cottages will be ADA

Accessible on the first level. In order to minimize the building footprint on the sloping site, each cottage will be a two-story structure. The Cottages are proposed to be constructed in pairs of two. Preliminary planning and concept design had envisioned each pair of cottages sharing an exterior deck area and retaining wall (reflected in the drawings and renderings provided); however, the design-build effort shall pursue the construction of each pair of cottages as connected duplexes in order to reduce costs, increase energy efficiency and construction efficiency.

Each cottage will include the following:

▪ A new dedicated heating, ventilation, air-conditioning, and exhaust systems.

▪ Sprinkler system.

▪ Fire Alarm system.

▪ Security system.

▪ Electrical service provided from the existing site electrical system.

▪ Fire protection and toilet flushing water supplied from the existing reclaimed water fire protection water distribution system.

▪ Domestic water supplied from the existing domestic water distribution system.

▪ Sanitary service connected to the existing sanitary system.

▪ Telecom connections for internet and VOIP telephone service.

▪ Sustainable design principles, including Passive House Design.

In addition to this narrative, Design-Build Bridging Documents provided include preliminary floor plans, elevations and renderings to facilitate the development of construction documents. These are provided for information only and may be revised during further

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design-build development.

1.3 APPLICABLE CODES, STANDARDS AND GUIDELINES

• International Building Code, 2015 Life Safety Code, NFPA 101, 2015 International Fire

Code, 2015 International Mechanical Code, 2015

• International Wildland-Urban Interface Code, 2015 National Fire Codes, 2017 Edition, especially:

• NFPA 13, Sprinkler Systems

• NFPA 72, National Fire Alarm Code

• NFPA 90A, Heating, Ventilating, and Air Conditioning Systems NFPA 220 Types of

Building Construction

• SI Office of Safety, Health, and Environmental Management Fire Protection and Life

Safety Design Manual, 2009

• ANSI A117.1, Accessible and Usable Buildings and Facilities, 2010 Uniform Federal

Accessibility Standards

• American with Disabilities Act Accessibility Guidelines Smithsonian Guidelines for

Accessible Design

Maryland Stormwater Management and Erosion & Sediment Control Guidelines for State and Federal Projects (February 2015)

These shall be confirmed by the Design-Build Team.

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2.0 SITE DEVELOPMENT

2.1 GENERAL

2.1.1 EXISTING CONDITIONS

The Green Village is a generally undeveloped site on a sloped area behind the existing dormitory building. It lies to the north of the dorm and trailer and east of the Schmidt Center.

The site is situated mid-way on the hill between the elevated water tanks and parking area

(called Woodland Parking) within what is considered the Core Campus. This site is within the drainage area to an existing stormwater pond at the northwest corner of the Woodland

Parking access and Java Farm Road. This turn off from Java Farm into the Woodland Parking provides almost immediate sight lines to the GV site; thus, there has been due consideration of how development of this site can bolster this particular entrance to campus while still providing a sense of seclusion and privacy inherent to a residential area.

2.1.2 PROPOSED CONDITIONS

The first two cottages which are envisioned to be sited just east of the Schmidt Center across from the existing Dormitory. The remaining four future cottages will be sited from west to east, following the grade along the hillside. This configuration offers a number of advantages:

• Maintains and reinforces sense of residential community

• Allows direct and universally accessible walking path to Schmidt Center

• Minimizes grading into steep slopes by placing the smaller building unit in the more difficult topographic gradient

• Avoids wetland and its buffer

• Remains compact while maintaining sufficient distance for privacy and fire safety

• Efficiently utilizes existing fire access lane

• Builds upon existing utility infrastructure

• Can be phased efficiently

2.2 APPLICABLE CODES AND STANDARDS

Maryland Stormwater Management and Erosion & Sediment Control Guidelines for State and Federal Projects (February 2015)

ADA Standards for Accessible Design (2010)

2.3 CIVIL

2.3.1 ACCESS

The Woodlands Parking Lot and drive aisle directly south of the existjng dormitory building serve as the only vehicular access point to the Green Village site. An asphalt and open grid paver driveway extends from Woodland Parking to the entrance of the Schmidt Center and runs along the length of the dormitory building. This mixed material driveway is the existing fire access to the dormitory and the Green Village facilities. It is also the bike and pedestrian access.

The existing fire lane requires two specific modifications to service the project’s new cottages: 1) A pedestrian access way to all cottages and 2) due to the length, an improved, PAGE -2.4 fire department compliant typical section and turn radii. The former is accommodated by adding an ADA accessible ramp and lead walk system to enter the units. A pedestrian path extension will be required from the end of the fire lane. The latter is accommodated by providing the required 20’ width (as asphalt rather than mixed material) for the full extents of the fire lane and relaxing the turning radii as much as possible to allow the fire truck 3-point turning movement. Also it should be noted that the length of the fire lane proper is restricted to 150’ of “backup movement”.

It is notable that a significant area of the existing lane’s open grid pavers along the east-west access of the drive must be removed for utility construction of the cottages. Thus, new pavement is required, anyway. Also notable is that the pavement cannot be open grid pavers because of the need to provide universal access to (at least) one of the first two cottages.

For cost efficiency, simple asphalt is proposed. Edging or additional materials may be incorporated.

2.3.2 GRADING

The first two cottages should be graded to be ADA accessible from the fire lane access drive.

This is achieved through a series of ramps and lead walks that meet the accessibility criteria.

2.4 UTILITIES

The Green Village site is, in many ways, a utility corridor today. Directly to the northwest of the Dormitory, there is a small maintenance/utility pad attached to the Schmidt Center, which houses a variety of electrical equipment, including a transformer and meter. BGE underground electrical lines run north and south between the Dormitory and Trailer T05 to the Woodlands Parking lot. From the parking lot, the lines turn east and west and transition from underground to overhead at a utility pole on the west side of the lot and remain underground heading east to Java Farm Road. Under the existing driveway north of the existing dorm is a small utility corridor where sewer, domestic water, fire suppression water

(non-potable), and various telecommunication lines run. These utilities are capped where the driveway ends, roughly 200 ft. from the entrance to the Schmidt Center. There is one existing fire hydrant on site that sits to the west of the Dormitory close to the Woodland

Parking lot. An existing MD-378 stormwater management pond- functionally in good repair based on limited observation- is located on the east side of the site at the Woodlands Parking entrance off of Java Farm Road however there is currently limited storm drain in the vicinity-only that directly associated with the existing dorm roof drain system- that would provide direct conveyance to the pond. There is an existing step pool stormwater management system between the existing dorm and woodland parking area, likely sized to address the existing dorm and limited surrounds.

The existing domestic water, sewer and fire protection utilities are adequate to serve all six

(6) cottages. The site utility improvements are to serve all six cottages. Utility pathways to serve the future Lodge are proposed to be stubbed and capped. This will limit future disturbance in the main fire lane corridor.

2.4.1 DOMESTIC WATER

The domestic water design maximizes the use of existing infrastructure running behind the

Dormitory. Each cottage is proposed to be served by a 1.5” copper potable water connections to the existing 4” DI water.

2.4.2 FIRE PROTECTION AND RECLAIMED WATER

In addition to domestic water, there is a requirement for fire protection water (non-potable

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water reclaimed water). There is an existing non-potable water system in the SERC campus which originates at a water tower north of the Green Village site. An 8” DI non-potable water line runs almost parallel to the 4” domestic water line along the Dormitory. Each cottage is proposed to be served by a new 4” DI house connections (for sprinkler service), a new 4” DI

FDC house connection, one new hydrant (for coverage purposes), one new remote FDC, and the portion of the cottage communal FDC system located under the fire lane. The reclaimed water service will also provide source water for toilet flushing and outside hose bibbs.

2.4.3 SEWER

The sewer main servicing the cottage corridor is located downstream of the domestic and non- potable water lines with minimum horizontal clearance. Each cottage is proposed to be served by a new 4” PVC house connections, which ties into the existing sewer system. It is assumed that the existing core campus septic system is adequately sized to accommodate the additional fixture load associated with this development program.

2.4.4 ELECTRICAL & TELECOMMUNICATIONS

Existing electric facilities traverse much of the Green Village site, both north and south on either side of the existing dorm and east west on the dorm and Green Village access road.

Site improvements include the relocation of one of the east-west electrical lines that is within the footprint of the first pair of cottages. This line provides service to the equipment northeast of the Schmidt Center. The equipment can be re-fed from the more recently constructed north south line in the water tank and fire suppression tank access road. This relocation is a nominal cost compared to the potential earthwork, wall, and site costs for relocating the two cottages either further uphill or further out into the forested hill or forested wetland area. In addition to the relocation, this will provide service connections to the first two cottages. Telecommunications will be extended from the existing telecommunications line running along the Dormitory with individual cottage services provided.

2.5 STORMWATER AND DRAINAGE

2.5.1 STORMWATER

The existing stormwater pond, constructed circa 2000 was designed as an “enhanced” extended detention pond. The “enhanced” refers to the creation of various marsh levels in the bottom of the pond. Maintenance and inspection records are not available; however, it is reasonable to assume that time alone has resulted in some sedimentation that could be exacerbated by construction in the drainage shed without proper protections. No owner reported problems are documented nor does the outfall reveal significant signs of washout, sediment, or erosion; thus, it is assumed the pond is performing adequately. Further recent investigations, including as-builts of the existing pond and dam safety inspection check list, have confirmed that the structures are performing adequately and the project has been resubmitted to MDE for approval.

From a regulatory standpoint, the Green Village site is within the drainage shed to the existing MD-378 stormwater management pond. This is both an asset and a challenge for the

Green Village Cottages. It is an asset in the sense that much, if not all, of the stormwater management requirements are already met for the site. Thus, the focus of the site design is capturing and conveying runoff to the pond and costs typically associated with stormwater management facilities are minimized. It is a challenge in that the facility itself is an outdated stormwater treatment type, and although it quantitatively appears to meet all the current requirements, it doesn’t do it in a desirable way from the standpoint of the prevailing agency

(MDE).

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The full build out of the Green Village seeks to reconcile this positive/negative site feature and transform it into a fully integrated, highly functional aspect of the landscape including re-branding as the Wetness Gradient Garden. By adding a forebay plus extending and redefining the marsh levels, the design simultaneously brings the facility more current with regulatory requirements while providing enhanced treatment potential that is both visible and experiential. Upon direct coordination with MDE (which typically occurs in a later phase of design when the first required regulatory plan—the SWM Concept—is prepared), this retrofit can largely be viewed as “intense” maintenance and an attempt to proactively address many of MDE’s likely concerns with using the outdated practice. Should MDE insist on some level of treatment via current preferred processes—defined as Environmental Site

Design (ESD) to the Maximum Extent Practical (MEP)— it is likely that a significant volume reduction to that which would otherwise need to be treated through these type practices will be achieved through credit from the pond. The GV design’s grading and drainage also incorporates several other practices that are be easily and cost efficiently converted to ESD type practices such as the swales on the upslope side of the cottages, as well as Filterras or similar products in the patio area. Further, based on the review of the pond design and outputs, it may be possible to make minor modifications to the riser (control) structure

(such as a plated/slightly smaller orifice, additional release orifices, modified weir, etc.) to address MDE concerns related to treatment volumes and release rates and/or provide some additional treatment enhancements such as a hood or upflow release pipe to help with temperature control downstream.

MDE has been engaged by the SI and A/E of record for the site improvements work and will continue coordinating and obtaining MDE approvals and permits for the project.

2.5.2 DRAINAGE

Overland water from rain events has been a concern for the existing Dormitory in the past, requiring post-construction measures to remedy water problems in the building. Currently, because of the steep slope of the fire access drive and the imperviousness of its surfaces act as a chute, accelerating water toward SERC Drive and across to Woodland Parking and causing mulch washouts and erosion. The steep slope, water velocity, and clay parent soil result in the grass pavers’ inability to grow grass. The upgraded fire lane with roadside drainage on the uphill side mentioned previously presents a simple and efficient drainage solution. Some use of trench drains may also be considered to reduce the volume of water sheeting overland and provide additional upslope/uphill pickup points.

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3.0 ARCHITECTURE

3.1 OVERVIEW

Green Village will provide a variety of housing options for scientists visiting the

Smithsonian Environmental Research Center. The project will provide accommodations in the existing dormitory, new lodge, and a collection of cottages.

Each cottage will consist of approximately 1200 gross square footage of living space on two floors. The first level contains shared common spaces, including a living room, kitchen and dining area, one bedroom with a full bathroom. Level two is proposed to consist of a shared office loft, one bedroom with a full bathroom.

The first two cottages are sited just across from the existing dormitory. The cottages’ architectural language proposes to borrow somewhat from the dormitory, which incorporates traditional features found in local residential design. These include the use of brick, horizontal siding, double-hung windows, simple roof lines and porches. The use of similar materials and color palette will unify the collection of buildings reinforcing the campus feel.

The massing of the cottages has been simplified to reduce construction cost while remaining true to the original aesthetic goals. The cottages have been carefully placed on site to reduce site disturbance and minimize site construction costs. The cottages are proposed to be designed as constructed as pairs. Each pair of cottages should be designed and constructed as connected duplexes.

3.2 APPLICABLE CODES AND STANDARDS

Refer to section 1.3

3.3 SUSTAINABLE STRATEGIES & TECHNOLOGIES

While not pursuing LEED Certification, sustainability is a key focus in the development of the

Green Village Cottages. Cottages are proposed to be designed for easy maintenance with materials that are durable and long lasting. Development of the cottages should investigate and incorporate, to the greatest degree feasible, sustainable strategies and technologies, including, but not limited to, the following:

Sustainable Strategies:

▪ Reclaimed water re-use for toilet flushing, irrigation and fire protection.

▪ Minimized site disturbance

▪ Use of recycled materials and / or locally-sourced materials (low-embodied energy)

▪ Greater insulation / thicker exterior walls.

▪ Reduced infrastructure (density & clustering).

▪ Attic spaces for thermal insulation and evacuation.

Sustainable Technologies:

▪ LED lighting (energy conservation).

▪ Low-flow plumbing fixtures (water conservation)

▪ Energy Star appliances and equipment (energy conservation)

▪ Insulated glazing windows units (reduced solar heat gain and ambient air loss).

▪ Low maintenance / high performance cladding materials (cement board, fiberglass entry doors)

▪ Porous pavers or grass paver systems.

▪ Ceiling Fans (air circulation to reduce cooling load).

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▪ Operable windows for natural ventilation

▪ Photovoltaics

▪ Solar Hot Water

Passive House Design:

• Utilize passive house design principles as deemed appropriate for the site and construction type.

• Reference the following information resources:

• Passive House Institute U.S. (Phius.org)

• Zero Energy Project (zeroenergyproject.org)

• International Passive House Association (passivehouse-international.org)

3.4 GENERAL COTTAGE PROGRAM

The SERC Master Plan identifies 6 cottages to be built as part of the Green Village.

Individual cottages are approximately 1200 gross square feet. Each unit is designed to accommodate a family, a single scientist, or combination of visiting scientists, depending upon need. General program requirements for each cottage are listed below:

▪ 1 Full Kitchen

• 1 Range with hood

• 1 Refrigerator

• Microwave on wall cabinet shelf

• 1 sink

• Full height pantry with pull out shelves

▪ Double height shared Living & Dining room with oversized ceiling fan

• bedrooms with 1 dedicated closet each and ceiling fan

• bathrooms with linen cabinet and open shelving, 1 ADA compliant

▪ 1 shared office loft

▪ Common laundry in each cottage

▪ Common coat closet near the front door

▪ Common Supply closet

3.5 COTTAGE CONSTRUCTION ASSEMBLIES

General descriptions of the proposed construction assemblies utilized for the cottages are identified below. These may be amended by the design-build team as required to comply with Passive House Design and Certification.

Foundations:

• Concrete slab on grade

• Single retaining wall / foundation wall along the North side of the cottages to minimize site disturbance.

Floor & Exterior Walls:

• 2x6 & 2x10 wood frame construction with plywood sheathing and vapor barrier. 2x10 construction for double height spaces can result in higher insulation values improving thermal performance

• Wood floor joists and plywood subfloors

• R20 minimum fiberglass insulation value or greater at exterior walls

• R20 minimum rigid insulation under first floor slab

Interior Walls:

• Typical walls: 2x4 wood studs with 5/8” GWB each side.

• Wall construction at mechanical closet: 2x6 wood studs, 5/8” GWB each side with

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acoustic batt in the cavity

Roof:

• Gable roof trusses.

• R30 minimum insulation value or greater.

• Continuous ridge and soffit vents.

3.6 MATERIALS

Provide durable, long-lasting materials, which are easy to maintain. Long lasting materials result in reduced environmental waste long term, while reducing the need for virgin materials to be extracted. The following are examples of proposed materials which may be utilized. These may be amended by the design-build team as required to comply with Passive House Design and Certification.

Exterior Materials:

▪ Standard brick at building base to cover foundation with precast concrete cap

▪ Cement board siding, wall shingles and trims

▪ Fiberglass roofing shingles laid on top of a peel and stick membrane

▪ Fiberglass windows with insulated glazing

▪ Insulated fiberglass entry door

▪ Galvanized gutters

Interior Materials:

▪ FSC certified wood cabinets in kitchen and bathrooms with quartz countertops and tile backsplashes

• Gypsum wall board for all interior walls and ceilings

• Low VOC carpet for bedrooms, loft, and stairs

• Low VOC luxury vinyl tile flooring in living, dining, and kitchen space

▪ Tile floors in bathrooms with tile base

▪ Square profile recycled rubber base in rooms with carpet or wood flooring

• Low-VOC paints and water-based finishes.

• All MDF and plywood shall be zero-VOC and use non-urea formaldehyde. Kirei or wheat board uses post-agricultural waste from sorghum or wheat. The discarded stalks are cut, pressed and formed using a non-toxic binding agent to create highly stable boards with structural properties comparable to MDF, OSB, and plywood. Wheat board emits no gasses or toxins, is easily machined and cut, resists moisture and rot, weighs less and is stronger than particle board or MDF.

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4.0 STRUCTURAL

4.1 DECRIPTION

The proposed structures are individual two-story cottages based on typical residential construction appropriate for the project location.

4.2 FOUNDATION SYSTEM

Based on recommendations from a preliminary geotechnical investigation, a shallow foundation system is appropriate for both the cottages. The anticipated allowable bearing pressure will be between 2000-psf and 3000-psf. A final geotechnical investigation will be required once the structures have been located on the site.

Foundations will be cast in place reinforced concrete. Isolated spread footings and pedestals will support columns and continuous strip footings will support concrete foundation walls and bearing walls. Where the structures extend into the hillside, creating a grade differential or daylight basement condition, cantilevered concrete retaining walls will be required. Temporary support and dewatering should be anticipated where proper soil layback cannot be achieved during excavation.

Interior slabs on grade will be 5-inches thick reinforced with welded wire fabric. A 4-inch layer of clean crushed stone over a 15-mil vapor barrier is required below all interior slabs.

A perimeter foundation drainage system will be required around each building. Where there are finished interior spaces below grade, an under-slab drainage system will also be required.

4.3 SUPERSTRUCTURE

The Cottages are proposed to be two-story units constructed of conventional sawn lumber and pre-engineered beams. Load bearing stud walls will typically be Hem Fir #2, 2x6 sawn lumber spaced at 16- inches. The clerestory double height space will have larger studs.

Floor framing will be 2x10 joists spaced at 16-inches. Floor sheathing will be 23/32 APA rated tongue and groove glued and nailed STURD-I-FLOOR.

Roof construction is proposed to be pre-engineered gable roof trusses spaced at 24-inches maximum. Roof sheathing will be 19/32 APA rated plywood or oriented strand board perpendicular to supports.

The primary lateral system for the cottages will be plywood or oriented strand board shear walls. At areas of discontinuity, strap ties will be used to drag load into the shear walls.

Hold-downs into foundations may be required. Where there is not enough length of shear wall, diagonal strap bracing may be required.

4.4 APPLICABLE CODES AND STANDARDS

IBC 2015 2015 International Building Code

ASCE 7 American Society of Civil Engineers - Minimum Design Loads for Buildings and

Other Structures

ACI 318 American Concrete Institute – Building Code requirements for Structural

Concrete AISC 360 American Institute of Steel Construction - Specification for Structural Steel Buildings SJI Steel Joist Institute

AISI American Iron and Steel Institute SSMA Steel Stud Manufacturers Association ASTM American Society for Testing and Materials

AWS D1.1 American Welding Society - Structural Welding Code for Steel

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4.5 STRUCTURAL DESIGN CRITERIA

ASCE 7-10, Table 1.5-1

Risk Category of Buildings and Other StructuresII

4.5.1 DESIGN DEAD LOADS

Dead loads for the purpose of structural design will be the actual weight of construction material and fixed equipment but will not be less than the unit dead loads prescribed in

ASCE 7.

4.5.2 DESIGN LIVE LOADS

Common / Public Rooms 100 psf

Stairs / Corridors / Exits 100 psf

Private Rooms 40 psf

4.5.3 SNOW LOAD CRITERIA

Ground Snow Load PG = 25 psf

Snow Importance Factor IS = 1.0

Exposure Factor (Partially Exposed) CE = 1.0

Thermal Factor CT = 1.0

4.5.4 SEISMIC LOAD CRITERIA

Soil Site Classification D*

(*Based on preliminary geotechnical investigation)

Seismic Importance Factor

IE =1.0

Mapped MCE Spectral Response

Accel. at Short Periods

SS = 0.116g

Mapped MCE Spectral Response

Accel. at Period of 1-Sec

S1 = 0.050g

Design Earthquake Spectral Response

Accel. Parameter at Short Periods

SDS = 0.124g

Design Earthquake Spectral Response

Accel. Parameter at 1-Sec Period

SD1 = 0.080g

Seismic Design Category B

4.5.5 WIND LOAD CRITERIA

Type of Structure Enclosed

Basic Wind Speed (3 second gust) 115 mph

Exposure ‘B’

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4.6 MATERIALS

Anchor Bolts ASTM F1554 Gr. 55

Structural Bolts ASTM A325

Wire Mesh ASTM A1064

Wood HF#2 or SPF#2

Glu-laminated Beams 24F-V4

Bar Joists K-type (2½” Brg)

Reinforcing Bars A615 Gr 60

Concrete Strength at 28 days:

• Foundations, piers and pedestals 4500 psi

• Foundation walls 4500 psi

• Exterior slab on grade 4500 psi

• Exterior equipment pads 4500 psi

• Slab on metal deck 3500 psi

• Interior slab on grade 3000 psi

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5.0 MECHANICAL

5.1 APPLICABLE CODES AND STANDARDS

International Building Code (IBC) 2015

International Energy Conservation Code (IECC) 2015 International Mechanical Code

(IMC) 2015

NFPA 70, National Electric Code NFPA 72, National Fire Alarm Code

NFPA 90A, Standard for the Installation of Air-Conditioning and Ventilating Systems

Occupational Safety and Health Act (OSHA)

ASHRAE Standard 55-2017: Thermal Environmental Conditions for Human Occupancy

ASHRAE Standard 62.2-2016: Ventilation for Acceptable Indoor Air Quality

ASHRAE Standard 90.1-2016: Energy Standard for Buildings except Low-Rise Residential

Buildings ASHRAE HVAC Systems and Equipment Handbooks

ASHRAE HVAC Fundamentals Handbooks ASHRAE HVAC Applications Handbooks

5.2 DESIGN CRITERIA Outdoor

Summer outdoor design conditions shall be based upon the ASHRAE Fundamentals

Handbook 0.4% conditions for Baltimore, MD.

Winter outdoor design conditions shall be based upon the ASHRAE Fundamentals

Handbook 99.6% winter conditions for Baltimore, MD.

Indoor

Bedrooms / Office / Living Room - Summer

Occupied: 70°F to 75°F (adjustable) and 55% RH max Unoccupied: 85°F (adjustable) and 60% RH max

Bedrooms / Office / Living Room - Winter Occupied: 67°F to 72°F (adjustable)

Unoccupied: 45°F (adjustable)

Ventilation

The Bedroom, Office and Living room spaces have windows and/or doors opening directly to the building exterior and the amount of openable area meets or exceed the minimum requirement for the use of natural ventilation required by the International Mechanical

Code (IMC). Please note that the proposed design does not include the mechanical ventilation system required by ASHRAE

62.2 for buildings that are thermally conditioned for more than 876 hours per year.

Bathrooms will be exhausted at a rate equal to the greater of: 10 Air Changes per hour, or IMC code minimum.

Kitchen Area to be exhausted at a rate equal to the greater of: IMC code minimum, or

Kitchen Hood Exhaust Air Flow Rate.

5.3 PRPOSED HVAC SYSTEMS

Note that the following may be amended by the design-build team as required to comply with Passive House Design and Certification.

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Cottage Heating and Cooling

Each Cottage is proposed to be provided with a vertical Split Heat Pump Unit for heating and cooling. The indoor air handling unit (AC) will have a variable speed supply fan, 30% pleated filter and a supplemental electric resistance heating coil. Integral unit controls will reduce fan speed when dehumidification is required. The supplemental electric resistance heating coil will provide heat under extremely cold conditions when the heat pump is unable to provide enough heat to maintain the temperature setpoint. The indoor unit will be housed in a new closet, constructed to minimize noise transmission to the adjacent spaces. A concrete pad will be provided behind the cottage for the condensing unit (CU).

Each cottage will be controlled through centrally located space temperature and humidity sensors which will be used to control the heat pump. Supply air will be ducted to each occupied space, and the return air will be drawn to a single inlet point in the living room.

Door undercuts or transfer grilles will be provided for each bedroom to serve as a return air pathway. Soffits will be provided along the edge of the bedrooms and living room to enclose all horizontal ductwork.

Ceiling fans will be provided in each bedroom, and above the high-bay living area to promote air mixing and improve overall occupant comfort. Each ceiling fan will be controlled by a local wall switch.

Electric Radiant Ceiling Panels (ERP) will be provided in each Bathroom.

5.4 PROPOSED EXHAUST SYSTEMS

Each bathroom and shower room will be provided with a ceiling-mounted exhaust fan.

The fans will be ducted to exhaust louvers in the exterior wall. A duct mounted backdraft damper mounted adjacent to the exterior wall eliminates the need to insulate this duct runout. Each fan will be controlled by a local fan switch, located adjacent to the light switch.

A hood will be provided above the residential-grade range in the kitchen. The hood will be equipped with an integral fan and local fan speed control. It will be ducted directly to a vent in the exterior wall.

Each clothes dryer will be directly ducted through the exterior wall to a dryer exhaust wall cap with integral backdraft damper (flapper type).

5.5 BUILDING AUTOMATION SYSTEM

All HVAC systems will be direct digital control and connected to the Siemens campus network.

The vertical Split Heat Pump Unit will be equipped with self-contained controls to maintain space temperature and humidity at setpoint. A BAS interface will be provided to permit the unit to be remotely enabled/disabled and alarmed. The BAS shall also monitor space temperature and humidity. An unoccupied mode override push button shall be provided.

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6.0 PLUMBING

6.1 OVERVIEW

Each of the cottages is proposed to have two bathrooms, each with a shower, water closet and a lavatory. The First-Floor bathroom will be designed with fixtures that meet ADA requirements. Additionally, there is a residential style kitchen with a sink, and residential-type clothes washing machine.

6.2 DESIGN CRITERIA

The design and installation of all drainage and service piping shall be in accordance with all prevailing codes, standards and guidelines including but not limited to the following:

• 2015 International Plumbing Code

• 2015 International Building Code

• ASME/ANSI B31: Code for Pressure Piping

• ASME Boiler and Pressure Vessel Codes

• ANSI A13.1: Scheme for Identification of Piping Systems

• NSF/ANSI 61: Drinking Water System Components

6.3 PROPOSED DESIGN

Plumbing and piping systems will be provided as required to serve the cottages. These systems will consist of domestic hot and cold water, reclaimed water to serve fire protection needs, toilet flushing, and exterior hose bibs / irrigation needs, sanitary waste and vent, and storm water. There is no natural available gas on site.

6.3.1 GENERAL

All domestic water piping, and reclaimed water piping, services will be provided with branch isolation valves for each floor, each room or area they supply, at each fixture or piece of equipment.

Sleeves shall be provided for all piping penetrations at walls and floors and through roofs.

Fire stopping shall be provided for all piping penetrations at walls, floors, and through roofs. The fire stopping materials shall be tested to meet ASTM E814 standard. Fire stop material shall not contain refractory ceramic fibers and shall meet the requirements of

NFPA 101.

Identification shall be provided for all piping systems, valves, equipment, etc. Marker and color legend shall comply with ANSI and OSHA standards.

6.3.2 SANITARY WASTE & VENT

Each cottage is proposed to have a 4” sanitary main exiting the cottage by gravity.

All sanitary waste piping will be located under the building slab or above ceiling elevations with vertical stacks located in chases in finished spaces. All cleanouts in the drainage system shall be completely accessible.

The sanitary drainage flow rates and pipe sizes shall be based on drainage fixture unit values of the actual fixtures and appropriate plumbing code specified diversity factors and allowances.

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Floor drains will be provided in the mechanical rooms where the water heaters are located and any other equipment requiring a drain. Drains and traps that are subject to evaporation shall be provided with trap primers.

6.3.3 STORM WATER DRAINAGE

A gutter and downspout system on the exterior of each cottage will be used to direct storm water to the underground storm sewer.

The building storm drainage system shall be sized in accordance with tables and flow rates as stated in the plumbing code.

6.3.4 POTABLE COLD WATER

A new 1-inch domestic water service will be provided for each cottage. Each new water service will have a reduced pressure zone assembly type backflow preventer and water meter with strainer assembly located in the mechanical room.

There is adequate water pressure on site to maintain pressure at the second floor.

The potable cold-water piping will be sized to maintain 35 psig at the most remote flushing fixture. Backflow preventers and pressure regulators will be provided for domestic and mechanical equipment water connections where necessary.

Water velocity in the cold-water distribution piping shall not exceed 8 feet per second and provisions shall be made to arrest water hammer. System capacities for cold water will be based on fixture unit values with appropriate diversity factors and actual equipment demands.

A non-freeze exterior wall hydrant shall be provided at each cottage.

The entire distribution system shall be insulated with ½-inch mineral fiberglass insulation.

The distribution system shall be sterilized with hypochlorite solution.

6.3.5 POTABLE HOT WATER

Each cottage will have an electric, high efficiency, storage type water heater. The water heater will have a storage capacity of 40 gallons.

Domestic hot water shall be generated at 120 degrees F by the water heater. A thermostatic mixing valve shall be provided to deliver hot water at a temperature of 110 degrees F to plumbing fixtures and domestic equipment.

The potable hot water piping shall be sized to maintain 30 psig at the most hydraulically remote fixture or equipment connection. Water velocity in the hot water distribution piping shall not exceed 6 feet per second. System capacities for hot water will be based on fixture unit values with appropriate diversity factors and actual equipment demands. Backflow preventers and pressure regulators will be provided for equipment water connections where necessary.

The entire potable hot water system will be insulated with 1-inch mineral fiber type insulation.

The potable hot water system will be sterilized with hypochlorite solution.

6.3.6 NON-POTABLE RECLAIMED WATER

A new 1-inch domestic water service will be provided for each cottage. Each new water service will have a reduced pressure zone assembly type backflow preventer and water meter with strainer assembly located in the mechanical room.

There is adequate water pressure on site to maintain pressure at the second floor.

The potable cold-water piping will be sized to maintain 35 psig at the most remote flushing fixture. Backflow preventers and pressure regulators will be provided for domestic and

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mechanical equipment water connections where necessary.

Water velocity in the cold-water distribution piping shall not exceed 8 feet per second and provisions shall be made to arrest water hammer. System capacities for cold water will be based on fixture unit values with appropriate diversity factors and actual equipment demands.

A non-freeze wall hydrant shall be provided at each cottage.

The entire distribution system shall be insulated with ½-inch mineral fiberglass insulation.

The distribution system shall be sterilized with hypochlorite solution.

6.3.7 PLUMBING FIXTURES & SPECIALTIES

Water Closets: 1.1 gpf, floor mounted, floor outlet, pressure assisted or high performance, 10-year warranty.

Lavatories: Countertop type units with 1.5 gpm flow, manual faucets with single lever actuation.

Kitchen Sinks: Countertop type units, undermount stainless steel with 1.5 gpm flow manual faucets with single lever handles and side sprays.

Showers: 60” x 30” acrylic enclosures with exposed thermostatic shower valve assemblies and 1.5 gpm flow restrictors. ADA units shall be provided with ADA thresholds, hand sprays on sliding mounts, fold-up seats and ADA grab bars.

Backflow Preventers: Reduced pressure zone.

Wall Hydrant: ¾-inch wall hydrant with vacuum breaker – recessed box type wall hydrant.

6.3.8 MATERIALS OF CONSTRUCTION

Listed below are the materials that will be provided and specified.

Piping Specifications:

San. Waste & Vent Above Grade: No-Hub service weight cast iron soil pipe with heavy duty couplings and DWV copper tubing with lead free soldered joints.

Below Grade: Service weight cast iron soil pipe with bell and spigot push on gasketed joints.

Storm Water Above Grade: No-Hub cast iron soil pipe with heavy duty couplings.

Below Grade Service weight cast iron soil pipe with bell and spigot push on gasketed joint

Insulation: Fiberglass on horizontal piping within the building.

Domestic Type L copper with lead free soldered joints

Cold and Hot Water Insulation: Fiberglass

Valves: Bronze ball type for sizes 2 ½” and smaller, epoxy coated iron ball valves for sizes 3” and larger.

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7.0 ELECTRICAL

7.1 GENERAL

The Green Village Cottages at the Smithsonian Institution’s Environmental Research Center

(SERC) in Edgewater, Maryland, provide housing for visiting scientists. Each two-story cottage is approximately 1,200 GSF, comprised of 2 bedrooms, 1 office loft, 1 living room, 2 bathrooms, and a kitchen space. Each cottage will be equipped with new dedicated heating, ventilation, air-conditioning, and exhaust equipment.

7.2 APPLICABLE CODES AND STANDARDS

International Building Code (IBC) 2017

International Energy Conservation Code (IECC) 20015 National Electrical Code, NFPA 70

(NEC), 2017 Edition NFPA 72, National Fire Alarm Code

National Electrical Safety Code, ANSI C2, Latest Edition Occupational Safety and Health Act

(OSHA)

Smithsonian Institution Codes, Standards and Guidelines, Latest Edition National Electrical

Manufacturer’s Association (NEMA)

Underwriters’ Laboratories, Inc., (UL) Baltimore Gas & Electric Company (BG&E)

7.3 EXISTING CONDITIONS

BG&E supplies electrical power to the entire SERC campus at medium voltage of 13.2kV via

Contees Wharf Road. The medium voltage line extends throughout the campus on overhead poles and underground cables to (BG&E) pad-mount transformers suppling secondary service to all the buildings on the SERC property. Secondary service to each or group of buildings is either 480/277V or 208/120V Wye. The secondary service at the Schmidt utility yard consists of a 225kVA, 208/120V-Y, 3-phase BG&E outdoor pad-mount transformer and utility revenue meter that serves an outdoor switchboard in the utility yard suppling power to the Schmidt Building, the Dormitory and Trailer. BG&E’s primary underground line to their transformer comes from Java Farm Road onto the maintenance drive in front of the

Dormitory and north along the east side of the Dormitory to the utility yard on the fire access lane north of the Dormitory. BG&E’s primary line continues down the maintenance road to other buildings on the Research Campus and also north to the old water tower alongside of the Schmidt utility yard.

The Schmidt utility yard also has an 180kW, 480/277V, 3-Phase diesel drive standby generator for electrical power supply upon loss of BG&E. This generator supplies standby electric power to the Schmidt building, the Dormitory and Trailer via an automatic transfer switch and step-down transformer located in the outdoor switchboard only when the utility power is lost.

The outdoor switchboard feeders to Schmidt, the Dormitory and Trailer are located underground and will need to be marked when construction of the fire lane and its underground utilities for Phase 1 construction, in order to maintain power to these facilities.

Under the utility yard project circa 2009 a distribution panel was added to the exterior east wall of the Dormitory for the potential of supplying power to GV cottages. In accordance with the 2008 contract documents, this panel has the potential for service in Phase 2 (4

Cottages) in lieu of power from the Schmidt utility yard. This will have to be confirmed by an equipment survey.

7.4 GENERAL REQUIREMENTS

Each Cottage will need Life Safety emergency egress lighting and exit signs with individual battery back-up per code. The purpose of the standby generators at SERC are strictly for utility back-up power; they are not for code required ‘Emergency’ and not arranged according to code requirements.

Each Cottage will require a minimum of 150A, 208/120V single-phase service based on the preliminary load calculations. Relay panels will allow demand control by the BAS for load curtailment during peak power demand as necessary for load curtailment on the existing standby generator, since the generator does not have the capacity to power the existing loads and the two additional cottages during peak time(s).

Each Cottage will require UL listed service equipment and service grounding electrodes consisting of 10 foot copper-clad ground rods and bonding of the domestic water pipe.

Arc-Fault circuit breakers are required by code for each Cottage. Minimum wire size and type shall be #12AWG THHN/THWN-2 copper. Minimum raceway size shall be ¾ inch in accordance with SI standards.

EMT raceways will be utilized for all low voltage drops in walls from accessible ceiling/area for cable pathways TBD.

All receptacles and light switches will be commercial grade with Lexan cover plates.

Residential grade will not be allowed due to longevity of commercial grade devices.

All light fixtures shall be LED low-medium commercial grade. Residential grade will not be allowed due to longevity of commercial grade units.

Panelboard construction will be utilized for cottages and Lodge. Load centers will not be allowed.

All disconnect switches shall be heavy duty (HD) commercial grade. General Duty (GD) switches will not allowed.

All junction boxes shall be metallic. Plastic will not be allowed.

Nonmetallic-sheathed cable Type NM will be used in the cottages and armored cable (AC) will be used in the Lodge for branch circuits. Although Type NM cable is allowed by code in the Lodge, this will only be considered as an acceptable VE item.

The following determinations are based on preliminary load calculations while maintaining utility and emergency power services to the existing Schmidt and Dormitory buildings. The load calculations will be refined and confirmed during detail design of the new buildings. The maximum meter reading to date on the Schmidt switchboard is approximately 75kVA total and 280.9A maximum on Phase A. This allows approximately 78kW spare capacity on the generator at 85% continuous load or 100kW momentary load. Preliminary load calculations on the service feeders to each building type and the three construction phases are located in the Appendix.

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7.5 EXTERIOR LIGHTING

All the following site lighting will be on TOD schedule through the BAS, except where otherwise noted.

a) Fire Access Lane: The existing two existing lamp posts (north of Dormitory along drive) will remain. Reference Site Infrastructure drawings for new and existing lamp post locations.

b) Cottages: Wall LED sconces at entrances/shared terrace spaces will be controlled within the cottage.

c) Path between Lodge and cottages: Phase 2 will include bollards @ 15’OC on one side of path (+/- 9 bollards in total).

7.6 PHOTOVOLTAICS

The cottages should be designed and constructed so as to allow for the possible future installation of photovoltaic arrays. Note that the proposed PV array for each Cottage should include PV control equipment and DC to AC inverters for connection into the main distribution panel at each Cottage via branch circuit breaker(s). Inverter sizes and wiring arrangements will be coordinated with final array layouts and panels. Coordination of net metering requirements for the PV installation will need to be coordinated with BG&E utility requirements.

a) ADA Cottage to have 18 PVs

b) Non-ADA Cottage to have 24 PVs

c) SunPower X-Series Commercial Solar Panels X21-345-COM

8.0 LIFE SAFETY / FIRE PROTECTION

8.1 GENERAL

The Green Village Cottages at the Smithsonian Environmental Research Center (SERC) in Edgewater, Maryland, provides housing for visiting scientists. Each two-story cottage is approximately 1,200 GSF, comprised of 2 bedrooms, 1 office loft, 1 living room, 2 bathrooms, and a kitchen space. Each cottage will be equipped with new dedicated heating, ventilation, air-conditioning, and exhaust equipment.

The buildings will be fully sprinklered in accordance with NFPA 13.

8.2 APPLICABLE CODES AND STANDARDS

International Building Code, 2015 Life Safety Code, NFPA 101, 2015 International Fire

Code, 2015 International Mechanical Code, 2015

International Wildland-Urban Interface Code, 2015 National Fire Codes, 2017 Edition, especially:

NFPA 13, Sprinkler Systems

NFPA 72, National Fire Alarm Code

NFPA 90A, Heating, Ventilating, and Air Conditioning Systems NFPA 220 Types of Building

Construction

SI Office of Safety, Health, and Environmental Management Fire Protection and Life

Safety Design Manual, 2009

ANSI A117.1, Accessible and Usable Buildings and Facilities, 2010 Uniform Federal

Accessibility Standards

American with Disabilities Act Accessibility Guidelines Smithsonian Guidelines for

Accessible Design

8.3 USE GROUP AND OCCUPANCY

Under the International Building Code (IBC) Cottages will be classified as R-3, Congregate Living facilities with fewer than 10 transient occupants.

Under the Life Safety Code, the Cottages will be classified as Lodging or Rooming House, under Chapter 26. These are defined as buildings that provide sleeping accommodations for 16 or fewer persons on a permanent or temporary basis, with or without meals, but without separate cooking facilities for individual occupants.

There are no other building occupancies or auxiliary uses.

8.4 BUILDING CONSTRUCTION AND HEIGHT/AREA

Proposed construction type for the Cottages is Type VB, unprotected wood frame construction. SI-OSHEM approval of this construction type will be required. Under VB construction type there is no fire resistance rating for the structural elements.

Allowable construction height is 4 stories or 60 feet for an R-3 occupancy that is fully sprinklered in accordance with NFPA 13. The building is 2 stories with an attic. There will be a sprinkler system installed in accordance with NFPA 13.

Allowable area under the IBC is unlimited for an R-3 occupancy of Type VB construction.

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The cottages are located 27 feet apart at the closest point. Taking fire separation distance

(FSD) line as equidistant from each building, this gives a FSD of 13.5 feet. Based on IBC

Table 602 for Type VB construction…