1 Introduction

Hord Coplan Macht recognizes and has restaurant and/or residential units at responded to our client’s desires to create the street-level and residential units at high-density, multi-family projects that the upper-levels, while mitigating the harmonizes into the urban context. Very impact of parking for these mixed-use often the project’s viability requires the buildings on the urban scene by providing integration of mixed-uses all within a parking below grade or in a structure single building. Aside from residential, behind and/or within the mixed-use these uses often include retail, restaurant, buildings. Depending on the challenges office and structured parking. A cost and opportunities of the project, these effective means to achieve this is through buildings can be designed as podium podium and wrapper buildings. While buildings (residential above mixed-use or designing these complex projects, we parking), wrapper buildings (residential have identified an opportunity to answer or mixed-use around parking) or a our clients’ questions on some of the combination of both. Properly designed, design strategies that can be used for these mixed-use developments maximize these mixed-use buildings. In an effort the density of the site and encourage to further educate our clients on design the active, pedestrian environment for a strategies, this white paper identifies the successful urban project. opportunities and challenges that the building code provides for podium and This paper identifies some successful wrapper buildings, while also identifying design strategies, which can be used to some additional design challenges of the develop these projects as podium and/ buildings and construction types we have or wrapper buildings. Our interpretations encountered through our experience. of the International Building Code 2012 (IBC) are based on our experience Architectural and land planning and discussions with a building code design in dense urban environments consultant; however, local building provides opportunities to focus on code officials have the final authority core placemaking principles. This is in determining the applicability and accomplished by designing mixed- interpretation of building codes to specific use buildings to reinforce the public projects. street, strengthen existing pedestrian circulation, define public open space and create private courtyards for residents. Design solutions include creating retail,

2 Crosswinds at Annapolis Town Center, a Market-rate Apartment Podium Building in Annapolis, MD Client: The Bozzuto Group

3 Podium Buildings

Construction Applicable Materials Building Height Range Stories Allowed Type B Building fully sprinklered Residential use / Building fully sprinklered

I and II Concrete, Steel, Metal Studs Unlimited Unlimited

Exterior - Metal Studs or Fire-Re- III tardant Treated (FRT) Wood 75’-85’ 5 Building Code (IBC) Interior - Standard Wood

V Standard Wood 60’-70’ 4 An important factor in developing these buildings is understanding In today’s market, the price of framed construction pushes the exterior walls and the wood the limitations and opportunities Type I and II construction and limit of the structural abilities of framed interior walls needs that the building code provides. the affordability of the housing the wood framing. This presents to be taken into account. A For these buildings, four types market are limiting a developer’s challenges including the spacing possible strategy that addresses of construction materials are ability to make a project work and size of the studs on the lower these concerns is designing a typically used for the structure. financially. Type V construction floors. Additionally, if the load- composite structure in which These include concrete, steel, is the most economical option, bearing walls are constructed the non-load bearing unit walls metal studs and wood. The IBC but has the greatest limit on with wood framing, wood and floors are framed out of designates construction using the number of stories and shrinkage needs to be accounted wood and a structural load concrete, steel and metal studs height per the IBC, limiting the for in the design. Typically, wood bearing metal frame is used. (non-combustible) as Type I density of the development. framing shrinks about 3/8” per Coordination amongst the or Type II construction, wood Type III construction provides a floor, or almost 2” over 5 floors, building trades needs to be taken construction (combustible) compromise between these other which must be accommodated into account when considering as Type V construction and construction types by taking in design and construction. The this composite structure. construction using non- advantage of the affordability of shrinkage mostly occurs during In this ever changing market, combustible or fire-retardant wood framed construction on the the first year of occupancy due structural design options need to treated wood exterior walls interior and the additional density to the moisture absorbed by be developed and estimated early and any construction type provided through the allowance the wood during construction in the design phase to determine on the interior as Type III of extra building height and and the acclimatization of the the most cost effective system construction. Generally, the stories with a non-combustible wood to the conditioned indoor for each project. lower the construction type, the or fire-retardant treated (FRT) environment. This shrinkage more building area and building wood exterior walls. Type III can be most problematic when height allowed (i.e., Type I construction presents some a masonry veneer is used on construction allows more building additional technical challenges the exterior, creating differential area and height than Type V because of the increased movement between the veneer construction). Understanding height and stories allowed in and the wood framed walls. If these basic limitations is critical the construction type. If fire- non-combustible walls are used to understanding the constraints retardant treated wood is used, on the exterior, the differential that the building code has on the five stories of load-bearing wood movement between the metal construction type and building.

4 For the purposes of this paper, podium buildings are defined as buildings in which an extra story is allowed for the construction type by creating a horizontal fire separation between the first floor above grade and the floors above. The upper floors are built above a podium structure. The building code has historically provided special provisions for podium buildings to allow for mixed-use and/or parking below the building to address the needs of cities that are aggressively focused on urban renewal. These special provisions have been refined through code revisions over the years. Crosswinds at Annapolis Town Centre, A Type V Podium Building Under Construction Client: The Bozzuto Group As of this publication (January 2014), there is a pending change to the 2015 IBC that would not limit the number of stories below the podium level to only one story. However, the height limit remains to be governed by the lesser construction type above the podium and is not a modification of the 2012 IBC. The potential new change is an interesting proposition that could allow a “5 over 3” podium building where the building is designed within the height limit of 85 feet using Type IIIA construction. Since the code modification is pending and state and local jurisdictions will still need time to adopt the new code, the risks of designing to this potential change must be understood by the designer and developer. Leake Hall - A Type V Podium Building Under Construction Client: MICA

Tysons West located in Tysons, VA. Client: The JBG Companies

5 Podium Option 1

GRADE GRADE PLANE PLANE

Diagrams Indicating Design Options of Construction Type VA, Podium Option 1 Building. Indicating Height, Story and Occupancy Limitations

Legend

CIRCULATION RESIDENTIAL/RETAIL/BUSINESS RESIDENTIAL

PARKING RESIDENTIAL/RETAIL/BUSINESS/RESTAURANT/PARKING

Option 1 utilizes special provision building above the fire separation type, which is the building over building above the horizontal 510.2 in the 2012 IBC. This can be of any construction type the fire separation. It is important fire separation due to building provision provides the greatest and can include residential, to understand that the building area, the fire wall is permitted to flexibility and creativity to restaurant, retail or offices. Wood height is determined from the terminate at the horizontal fire the design team and is most framed construction is the most calculated grade plane, which separation, or podium level. appropriate for mixed-use affordable for this portion of includes the building below the buildings designed as podium the building. The story below horizontal fire separation. In structures. By separating the the horizontal fire separation order to maximize the height, first floor above the average must be of Type IA construction the number of stories and grade plane with a three-hour and allows parking, residential, occupancies allowed, fully fire resistance rating from the restaurants, retail or offices in sprinklered buildings using building above, the building code any combination. The provision to NFPA 13 sprinkler systems are essentially allows an additional allow residential use below the required. However, NFPA 13R story for the most restrictive podium was adopted in 2009 sprinkler systems are permitted construction type (in stories) IBC as previous versions of the in the residential building above because the number of stories code did not list ‘residential’ as the fire separation when that allowed for the building is a permitted use. The maximum portion is a maximum of four determined from the horizontal height of the overall building is stories and no more than 60’ fire separation, not from the limited by the most restrictive above the calculated grade plane. calculated grade plane. The (in building height) construction If a fire wall is required in the

6 GRADE GRADE PLANE PLANE

Diagrams Indicating Design Options of Construction Type III, Podium Option 1 Buildings. Indicating Height, Story and Occupancy Limitations

Option 1 Summary

• Provides greatest flexibility and creativity to the design team

• Allows an additional story of construc- tion for Type III and Type V construction

• Allows residential, restaurant, retail, Crosswinds at Annapolis Town Centre - A Type V Podium Building Under Construction, business or parking occupancies above described as Option 1 Client: The Bozzuto Group the podium

• Allows parking, residential, restaurant, retail or business occupancies below the podium

• Any fire walls in the building above the podium can be terminated at the podium

The design of outdoor terraces is typically a feature of podium buildings. Above is pool courtyard at Crosswinds at Annapolis Town Centre. Client: The Bozzuto Group

7 Podium Option 2

GRADE PLANE

Amenities are easily incorporated into podium buildings such as The Galvan in Rockville, MD. Client: The JBG Companies Option 2 utilizes the special system. However, If an NFPA 13R provisions found in 510.4 in the sprinkler system is used in the IBC where parking is the only residential building above, (with use provided below the podium Type V construction) a two-hour GRADE with residential use above. separation is required. The building PLANE This provision also allows an height is determined from the additional story for the most calculated grade plane from the restrictive construction type (in ground level adjoining the finished stories) because the number of parking level below. Any fire walls stories allowed for the building is that are required in the building determined from the floor above above the separation because the parking level that is located of floor or building area must be no more than one story above the extended to the footings and may calculated grade plane. not be terminated at the horizontal The building above the podium separation. parking garage can be of any construction type, though wood Option 2 Summary framed construction is the most affordable. The provision • Allows an additional story of construction GRADE is more limiting than 510.2 PLANE because it only allows parking • Allows only residential above the podium Legend in the lowest story and only residential occupancies above CIRCULATION the separation. The separation • Allows only parking below the podium PARKING is only required to be one hour,

if the building is fully sprinklered • Any fire walls in the building above the RESIDENTIAL with an NFPA 13 sprinkler podium must be extended through the parking structure

Diagrams Indicating Design Options for Option 2 Podium Buildings

8 CASE STUDY: Village Lofts A Podium Building in Baltimore, MD

FIFTH FLOOR

FOURTH FLOOR

THIRD FLOOR

SECOND FLOOR

FIRST FLOOR

Village Lofts is a mixed-use development near the Johns Hopkins University Homewood campus in Baltimore, Maryland. The project GARAGE FLOOR is comprised of loft apartments, structured parking spaces and (SUBGRADE) neighborhood retail space. The exterior was designed to invigorate the street level with retail, awnings and outside dining on a wide, carefully landscaped sidewalk. The building facades pick up detail from neighborhood buildings while expressing that this is an exciting, vibrant midtown community.

Prototypical Site Plan Density Analysis Analysis based on 2 buildings in a typical block Stacking Diagrams

Site Area: 73,334 SF [1.68 AC] Residential Units: 136 in 2 buildings Yield: 80.95 DU/AC Parking: 174 private garage spaces in 2 buildings

Prototypical Site Plan

9 Wrapper Buildings

parking structure, wrapper buildings are a more viable solution than podium buildings when the local zoning ordinance limits the overall building height and there is ample site available to accommodate the separate parking structure.

Although the building code does not provide any special provisions specifically for wrapper buildings, it does provide opportunities for creative building code strategies that may minimize the fire resistance separation requirements and the mechanical ventilation and sprinkler requirements of the parking garage. These strategies include: This perspective shows a mix of uses including a Wrapper Building in the upper right. The design calls for market designing the residential/retail rate apartments around a parking structure with ground-floor retail space. The image depicts the plaza between the buildings with a wrapper building beyond. building as a separate building from the parking structure Wrapper buildings (also known in which a fire wall is shared as donut buildings) provide between the two buildings or another design option to develop designing the residential/retail a successful urban project that building as a separate building incorporates core placemaking from the parking structure where principles. By providing a pre- the two buildings are separated cast or cast-in-place parking by more than ten feet, potentially structure in the center of the allowing the parking structure to building and surrounding the be considered an open parking parking structure with residential garage. Each of these options is and/or mixed-use buildings, dependent on the opportunities the sidewalk at the street-level and challenges presented by is activated with traffic at the each specific project and site. pedestrian scale. Because the height of the residential/retail building is independent of the

10 Wrapper Option 1: Buildings Separated by More Than 10 Feet This option classifies the parking than 13 feet, the exterior wall of structure as a separate building the residential building can have from the retail/residential limited openings. Furthermore, building. By separating the consideration to create an open parking garage by more than separation on only a single 10 feet, the parking garage may side of the garage can be be considered open, eliminating incorporated into the design if the need for sprinklers and the limitation of an ‘open’ garage mechanical ventilation in the is maintained. garage. This option works well for single-loaded corridor GRADE PLANE configurations because openings are not permitted in Diagram indicating design option for a wrapper building in which the parking the residential building wall garage is separated from the residential building facing the parking garage. If the separation is increased to more

Wrapper Option 2: Separate Buildings Connected by a Fire Wall

This option classifies the parking structure as a separate building from the retail/residential building GRADE PLANE and requires a three-hour fire wall separating the buildings. If the parking structure is lower in height than the adjacent retail/ residential building, the building code will allow the fire wall to be terminated at a one-hour roof assembly on the parking garage. This design option allows for a Legend tighter footprint, however, this GRADE likely will classify the garage CIRCULATION PLANE as “enclosed” in which a PARKING sprinkler system and mechanical Diagrams indicating design options for a wrapper building in which the ventilation will be required. RESIDENTIAL parking garage and residential buildings are separated by a fire wall

11 Design Challenges of Wrapper Buildings

Circulation Diagram 1 Circulation Diagram 2 Parking and residential floors at different levels Parking and residential floors aligned

Circulation Construction Phasing Lot Size

Because of the potentially The parking garage in a wrapper Ramped parking garages Alternate design to address inherent different floor-to-floor heights building is typically of pre-cast require a minimum deck size to inefficiency of wrapper building between the parking structure construction. Though these are be efficient and to provide the and the residential/retail less expensive than poured- ramping between parking levels. building, circulation between in-place parking garages, they Providing a speed ramp in the Inefficiency the two buildings is complicated require a longer lead time for parking garage can address this Depending on the site, wrapper [Circulation Diagram 1]. This production. Additionally, the minimum size, but will increase buildings may be developed as can be addressed by providing erection of the parking garage is the amount of gross square feet single-loaded corridors, creating a pedestrian ramp between the more efficient and construction in the garage because parking a less efficient building plan and parking garage and the building, conflicts are avoided if the cannot be provided on the slope less residential units per floor. providing separate means parking garage is erected prior required for a speed ramp. There are creative options to of circulation in the parking to the start of construction of the design the residential building garage and the residential/retail residential/retail building. This with a double-loaded corridor. building, which are connected can be avoided by building a This includes creating wings with by a walkway at the first level cast-in-place concrete garage; double loaded corridors that do or aligning the floor heights however, the additional cost of not overlook the parking garage. of the parking garage with the cast-in-place garage has to [See diagram] the residential/retail building be weighed against the additional [Circulation Diagram 2]. This construction time cost inherent in last solution will address the the pre-cast garage. circulation concerns, but will increase the floor-to-floor height of the parking garage. Legend Therefore, the cost of the garage CIRCULATION will increase and the efficiency of the garage may decrease if PARKING the increased floor height of the RESIDENTIAL garage eliminates a parking level.

12 Combined Podium and Wrapper Buildings

In order to provide mixed-use projects (including residential, retail and restaurant) within wrapper buildings, a podium building may also be provided around the perimeter of the parking garage. This is accomplished through a combination of the strategies Diagram of design option combining a wrapper and podium building with a fire wall indicated above using Option 1 for podium buildings with Option 1 or 2 for wrapper buildings. Another alternative solution would be to design the building utilizing Option 1 of the podium building as a non-separated mixed-use building between the mixed-use building below the podium and the parking garage.

Legend

CIRCULATION

PARKING

RESIDENTIAL Diagrams of design options using podium and wrapper buildings as non separated RETAIL / BUSINESS / RESTAURANT mixed use buildings

13 CASE STUDY: Union Wharf A Combined Podium & Wrapper Building in Baltimore, MD

FIFTH FLOOR

Located on the waterfront in historic Fells Point, Union Wharf is a

FOURTH FLOOR 281 unit mixed-use development that embodies the character of its unique setting. The project features open, loft-like residences overlooking the harbor and multiple courtyards. A series of community amenity spaces wrap the main court and features a THIRD FLOOR dramatic pool and water element stretching from the building lobby to the water’s edge. A combination of residential units and retail uses are designed below the podium level.

SECOND FLOOR

Prototypical Site Plan Density Analysis Site Area: 148,000 SF/3.4AC FIRST FLOOR Residential Units: 281 Yield: 82.65 DU/AC Parking: 472 Private Garage Spaces in 2 buildings

Stacking Diagrams

14 Union Wharf, Baltimore, MD Client: The Bozzuto Group

Summary

Design solutions for dense urban environments are dependent on the program, lot size, zoning requirements, parking requirements, building height, and topography, to name a few. Generally, podium buildings tend to be more appropriate when the lot size is limited and the zoning allows a higher building height. Wrapper buildings work well when there is more land area available and less building height allowed per zoning. Other factors, such as financing and the target market, also affect the best design solution for a specific project.

This paper has identified some creative design solutions that can be used to maximize the density of the development and limit the cost of the project while still maintaining the core place-making principles Street-level retail is often integrated into the design below the that we feel are critical for an urban environment. podium level.

15 Project Experience

Podium Buildings Wrapper Buildings

Crosswinds at Annapolis Hunt Valley Mixed-Use Towne Centre Development Annapolis, MD Hunt Valley, MD The Galvan Oxford Square Rockville, MD Hanover, MD Tysons West Annapolis Junction Tysons Corner, VA Annapolis, MD Seminary Hill Seminary Overlook Alexandria, VA Alexandria, VA Leake Hall, MICA Baltimore, MD Combined Podium & Park Potomac Wrapper Buildings Potomac, MD Hawthorne Place Union Wharf Laurel,MD Baltimore, MD Cameron Park Mark Center Alexandria, VA Alexandria, VA 6410 Arlington Blvd South Alex Arlington, VA Alexandria, VA HORD COPLAN MACHT was founded in 1977 Evergreen at Columbia Vienna Crossing Vienna, VA Town Center with the goal of providing the highest quality architectural, Columbia, MD AVA Wheaton landscape architectural and planning services to our clients. Wheaton, MD Village Lofts Since our founding, we firmly believe in a collaborative, multi- Baltimore, MD Scout on the Circle City of Fairfax, VA disciplinary approach to problem solving. We strive for the The Marque at Heritage Hunt Gainesville, VA highest quality design which will, through the clarity of ideas Waverly Gardens and sensitivity to the environment, produce a compelling Columbia, MD project. We integrate our client’s financial, functional and Ellicott Gardens Laurel, MD aesthetic goals into buildings, landscapes and land plans that Ashbury Courts will be enjoyed by the end user. HCM has a diverse studio Laurel, MD environment with award-winning residential, healthcare, Patuxent Place education, landscape architecture and planning studios to Laurel, MD Remington Row serve the diverse needs of our clients. Baltimore, MD Brompton House The architects, landscape architects and planners at HCM Elkridge, MD believe in the creation of meaningful places. The notion of National Harbor “place” transcends throughout our studios in that we strive National Harbor, MD to create places to live, places to heal, places to learn or 530 First Street Alexandria, VA places to play. The planning of places collectively, form the Station Square East basis for everyday civic life. We draw our inspiration from the Pittsburgh, PA fundamental understanding that humans connect with places they clearly and empathetically understand. We recognize that places we create have value and an obligation to coexist with the environment. We embrace sustainability through BALTIMORE innovation and our commitment to a holistic design project. DENVER ALEXANDRIA www.hcm2.com