High-Rise Sample Standards
from Other Cities
Planning Commission Discussion
May 8, 2024
Design Standard Objectives – High-Rise
Development
• Create objective standards for new residential development that considers the unique aspects of high-rise design with Bergamot context • Shadow & Wind
• Analyze shadow and wind impacts on public streets and spaces • Cross Ventilation & Sunlight
• Maximize cross ventilation and sunlight opportunities in future development • Common Open Space
• Support the development of successful common open space within new development
• Ground Floor Open Space & Pedestrian Pathways
• Require ground floor open space and pedestrian pathways to support pedestrian mobility and public realm improvements
• Human-scale, Pedestrian-oriented Design
• Support ground floor / podium design consistent with human-scale, pedestrianoriented design Review of Sample Standards
• Defining ‘high-rise’
• Tower Massing
• Sky Exposure Plane
• Height to Width Ratios
• Floor Plate Maximums
• Tower Separation & Placement
• Façade Design
• Podium Massing
• Open Space + Pathways
• Solar Access
• Wind
Intent to introduce different approaches from other cities – not recommending any specific standards
➢ Los Angeles, San Diego, Long Beach, Vancouver, New York, San Jose When should “high-rise” standards apply?
City Height (ft) Height (approx.
stories)
DTLA Over 150 ft 14 stories
Long Beach Over 150 ft 14 stories
San Diego Over 125 ft 11 stories
San Jose Over 70 ft 6 stories (‘Skyline level’)
• Separate standards required due to:
• Different building typologies with different types of impacts that differ from the City’s existing low and mid-rise regulations • Prominent visibility in the City, contribute to the City’s skyline • Several cities have high rise standards, and each define high rise differently
• Existing max height in Bergamot – approx. 84 feet
• Current local “high-rise” height for Fire Code in SM is 55 feet 1770 Pendrell St, Vancouver
Tower Massing
Sample standards
• Ground floor setbacks
• Upper floor stepbacks
• Sky exposure plane
• Height to width ratios
• Floor plate maximums
The general focus of many existing tower
standards are to limit massing at upper levels to
support access to light and air, and maintain
views of the sky
Illustration of New York’s sky exposure plane massing regulation. Should there be standards the limit massing for taller buildings? Source: NYC Zoning Handbook Tower Massing: Sky Exposure Plane / Height to Width
Sample standards
• Sky exposure plane (NYC) –
intention to get sunlight to the street
The building or other structure shall not
penetrate the sky exposure plane set
forth in the table. (exceptions allowed in
certain circumstances).
• Height to width ratios (DTLA) –
intention to reduce overall massing
Towers have a ratio of height to width
of about 3.5:1, for example, 100 feet wide
and 350 feet tall.
Illustrations of New York’s sky
exposure plane massing
regulation.
Source: NYC Zoning Handbook
Tower Massing: Floor Plate Maximums
• Tower floor plates drive external
massing
• Tied to project viability
Considerations
Sample standards
• Vancouver
• Corner sites with frontages of 130 ft or more:
• Width: maximum 70 ft – 80 ft
• Floor plate: up to 5,500 sq. ft (Vancouver)
• San Diego
• Maximum floor plate (includes commercial):
Source: Vancouver West End Tower Form, Siting and Setbacks 2023 Should there be floor plate maximums? Should there be a maximum width, and/ or area? Floor Plate Maximums
For illustrative purposes
Smaller maximum tower floor
plates combined with
generous separation of
towers in Coal Harbor,
Vancouver
Tower Separation + Placement
Source: City of LA – Downtown Design Guide 2009
Sample standards
• Intention to allow for
light/air between bldgs
• DTLA
• The portion of a tower
above 150 feet shall be
spaced at least 80 feet from
all existing or possible future
towers, both on the same
block and across the street.
Intention:
Allow for light & air
between buildings
Tower Separation + Placement
620 First Ave, San Diego
Sample standards
• Long Beach / DTLA / Vancouver
• 80 foot minimum to any existing tower on
the same site or across the street
• NYC
• The required minimum distance between the
portion of a building containing dwelling units and
any other building shall vary according to the
height of such buildings and the presence
of legally required windows in
facing building walls:
• 40ft wall to wall;
• 50ft wall to window;
• 60ft window to window
Should there be requirements for tower spacing?
Façade Design
Considerations
• High rise prominence contributes to a City’s
identity
• Visual Interest
Sample standards
• Require balconies
• Require modulation
• Require use of vertical elements, including
modulation to complement form, e.g. no more
than 15 feet without a feature (San Jose)
A residential tower with vertical modules and
articulated with cantilevering balconies. Should there be requirements for façade articulation? 1181 Cadero St, Vancouver Façade Design
Modulated building forms with flat facades.
461 Dean Street, Brooklyn
Residential tower renderings showing modulation and articulation using material changes, emphasizing verticality in tower.
2000 South Bell Street, Arlington, VA
Façade Design
Modulated building forms using massing
and material variation
South Grand Ave Street, Los Angeles
A single, sculpted building module,
articulated with facade features like
screens and balconies
1568 Alberni Street, Vancouver
A residential tower with modules and articulated
with balconies
1100 S Hope Street, Los Angeles
Podium Massing
• Podium massing can establish or continue
a street wall at pedestrian level
• Some podiums cover almost entire lots –
may be a need to break up excessively
long ground floor massing
• Allowances for open space at street level
and pathways through the site
• Podium floor plate maximums or break
requirements may be options for limiting
lot coverage
Considerations
The Dime, Brooklyn:
A four story podium provides
common open space above
and activation on the street.
Should there be standards to shape podium massing?
Podium Massing
Standards apply specifically to the podium level
Sample standards
• Similar concept to existing streetwall
standards (e.g. Downtown Community Plan)
• Consider podium standards for above-ground parking
• Placement of tower relative to podium
San Jose – streetwall
• Create a Streetwall along a Primary
Addressing Street along at least 70% of the
property or setback line.
• Create a Streetwall along a Secondary
Addressing Street along at least 50% of the
property or setback line.
San Jose – podium level massing
• Divide Podium Level building massing facing
Public Space that creates a façade wider
than 100 feet into visibly articulated smaller
masses no wider than 80 feet using
projections and recesses, materials, shadow
relief, or other architectural elements. Source: City of San Jose – Downtown Design Guidelines and Standards 2020
Open Space + Pathways
• Common open space is likely to occur on podiums, rooftops, or ground level • Ground floor /podium footprint maximums could help support ground floor open space and pathways
Considerations
Open space on large podium with
no pathways through large block.
South Park, Los Angeles.
Two towers, not on podium, with ground
floor common OS and pathway through
block (not public). Upper floor is penthouse,
not common OS. San Diego, CA.
Open space on large podium with
no pathways. Rooftop open space.
Vancouver, Canada.
Solar Access
Considerations
• Time of year and time of day to protect spaces
• Maximizing sun in public spaces, especially during Winter hours
• Siting of development and massing
Sample standards
• (San Diego) The Overlay District must maintain adequate sunlight and air to designated areas of Little Italy during the winter solstice (on or about December 21) between
10:30 a.m. and 1:30 p.m. The Overlay establishes a building envelope, which applies to the whole block.
• (Sydney) Identified open spaces must retain a minimum of 3 hours of solar access, to at least 50% of the space,
between the hours of 9am and 3pm on December 21.
Source: City of San Jose – Downtown Design Guidelines and Standards 2020 Wind
Considerations
• Maximizing ventilation for residential units
• Preserving wind flow
• Mitigating vertical wind effect, e.g. canopies or
horizontal elements
• Mitigating wind effects on public streets & spaces
• Complexity of requiring wind studies for individual
projects
Sample standards
• San Jose
• Stagger the heights and locations of tall buildings in and between blocks to avoid blocking wind flows.
• Create gaps of 15-20 feet width in Podium Level
massing in the prevailing wind direction.
• Orient the widest Skyline Level building dimension
within 30 degrees of the prevailing wind direction.
Should there be standards for tower
placement for solar and wind
performance?
Considerations for Bergamot:
Solar / Wind Studies
Considerations for Solar/Wind Study
• Study impacts of building placement and orientation on solar access for on-site open space and public streets & spaces
• Highlight impact of wind/breeze when buildings placed to maximize solar access
• Develop understanding of whether there are objective standards to minimize downdraft
• Identify if building placement and orientation to optimize daylight is also favorable for breeze/passive ventilation.
Local Conditions – Solar + Wind
• Grid pattern about
45 degrees from
NS-EW alignment
• Prevailing winds
from the SW
Figure source: Bergamot Area Plan – May 2023
Prevailing
wind from
the SW
Prevailing
wind from
the SW
Sites for shade/shadow + wind testing
Site 3
A recent
preliminary
application in
the Bergamot
District
Site 2B
Infill site with
a south facing
open space
and through
block
circulation
Site 2A
Infill site with a
north facing
open space and
through block
circulation
Site 1
A typical site
residing at the
edge between
residential and
commercial
zones
Shade / shadow – Site 1
View from Northwest View from Southeast
Shade / shadow – Site 1
Dec 21, 3pm
June 21, 3pm
Dec 21, 10am Dec 21, noon
June 21, 9am June 21, noon
Shade / shadow – Site 2A & 2B
Site 2B
Site 2A
View from South View from East
View from South View from East
Shade / shadow – Site 2A & 2B
Dec 21, 10am Dec 21, noon Dec 21, 3pm
Dec 21, 10am Dec 21, noon Dec 21, 3pm
Site
2A
Site
2B
Shade / shadow – Site 2A & 2B
June 21,
3pm
June 21,
noon
June 21,
10am
Site
2A
June 21,
3pm
June 21,
noon
June 21,
10am
Site
2B
Shade / shadow – Site 3
Shade / shadow – Site 3
Dec 21, 10am Dec 21, noon Dec 21, 3pm
June 21, 10am June 21, noon June 21, 3pm
Wind – Site 1, 2A, 2B
• Wind behavior not as consistent as solar for modelling impacts
• Depending on orientation, building massing can increase or decrease wind impact
• Bergamot grid's parallel orientation to the prevailing wind presents contrasting effects of wind
• Site 1 - Tower spacing allows wind to pass through site Towers need separation to avoid a wind tunnel
• Site 2A/B - Less wind passing through, more
deflection
Site 1
Site 2A Site 2B
Wind
– Site 3
• Very little wind able to
pass through site
• Likely wind tunnel
effect through narrow
spaces
• Leeward side (eastern
side) potentially
turbulent with
disrupted airflow.
• Windward side downd
raught would require
mitigation Windward side
Leeward side
Guiding Questions
• Feedback on design standard objectives
• When should high-rise standards apply?
• Feedback on sample standards from other cities
• Should there be a maximum floor plate? Dimension? Area? • Should there be requirements for tower spacing?
• Should there be façade standards?
• Should there be tower positioning requirements for solar and or wind/ventilation performance?