The Laurel District:

How High? How Dense? and Where?

 

Summary of a

community workshop

held Monday, December 8, 2008

at Laurel Café

 

 

Presented by the

Laurel District Association

and the Mills College

Public Policy Program

 

 

 

 

 

 

 

 

February 2009

 

Introduction

The "Envisioning MacArthur Boulevard" process called for increased height and density along MacArthur Boulevard to take advantage of being a major transit corridor, and to create the density necessary to support a vibrant commercial corridor. In the citywide rezoning process we will have the opportunity to define How High? How Dense? and Where?

The Laurel District Association is working with Mills College Public Policy Program to help the community think about MacArthur Boulevard and the issues that will come up as part of the rezoning process. Community members gathered on Monday December 8th at 6:30 p.m. at Laurel Café to hear brief presentations from Mills College graduate students in Public Policy about key issues related to height and density to the Laurel District along MacArthur Boulevard, with examples of floor area ratios, and alternative design solutions.

The workshop concluded with a “visual preference survey” in which participants rated photographs of different design features as to their suitability for future development in the Laurel District. Mills students recorded comments from participants which are summarized here to promote further discussion and input into the citywide rezoning process.

 

 

Key Concepts

Zoning is about regulating land use and protecting property values. Traditionally, cities have designated separate zones for residential, commercial, and industrial uses to keep incompatible activities separate. Zoning ordinances can also control the height and density of buildings, how much parking is required, and other aspects of a community planning and design.

 

Mixed-use zoning is a newer strategy that recognizes that there are benefits to combining some activities within a single zoning district. If jobs and housing opportunities are allowed within the same zone, people may not need to commute as far and traffic congestion can be reduced.

 

Smart growth is a term to describe strategies that promote economic development while preserving or improving environmental amenities and community assets. Mixed-use zoning, transit-oriented developments, and walkable neighborhoods are often cited as examples of smart growth.

 

The citywide rezoning process is an effort by the City of Oakland to update its zoning ordinance to reflect its vision for future development. The current zoning ordinance is not consistent with the city’s General Plan, which was revised over a decade ago, and is widely seen as too complex, making it more confusing and costly for developers to propose new projects. Through the rezoning process, the zoning ordinance may be simplified, while at the same time encouraging neighborhoods within the city to make a positive statement about the types of development they hope to see.

 

Housing needs are an important consideration for planning future development in Oakland. The Association of Bay Area Governments estimates that Oakland will need to provide for an additional 14,629 housing units by the year 2014, distributed over a range of levels of affordability. Increasing the density of residential development or allowing residential units above commercial developments (an example of mixed-use zoning) may be used to promote a balance between jobs and housing.

 

Bulk and density are concerns when new developments in well established neighborhoods. Design techniques can be applied to minimize the impact of new buildings on the existing streetscape. These can include scaling and detailing of building façades; setback requirements to keep larger buildings from overshadowing adjacent lots; height or floor:area ratio limits; and skyplane setbacks (see below).

 

Additional planning tools besides zoning include specific plans, which are more detailed planning documents for a neighborhood, often prepared in conjunction with a proposed development; design standards, to provide guidance on the appearance of new buildings in relation to the surrounding neighborhood; and the environmental impact review process, in which members of the public can comment on potential impacts of new developments on the natural and social environment.

 

 

Building height:Street width ratio

A streetscape is the visual appearance of a neighborhood from the ground level, including buildings, landscaping, sidewalks, and the street pavement itself. When considering design guidelines for a commercial corridor such as MacArthur Boulevard in the Laurel District, an important aspect is the height of buildings to be allowed. While people’s aesthetic preferences may vary, some design principles can be applied to produce more generally pleasing streetscapes.

 

One such design principle concerns the ratio of building heights to the width of the street. Where buildings are low and the street very wide, the streetscape can seem overly exposed or isolating, especially for pedestrians. Conversely, when very tall buildings crowd around a narrow street, they produce a canyon effect, as seen in Manhattan or parts of downtown San Francisco; wind speeds and noise can be amplified and natural lighting is reduced. Between these extremes, a balance between building heights and street widths can give the streetscape the proportions of a “room,” which is a more comfortable space for most people than an open plain or a canyon.

 

Achieving a suitable balance between building height and street width requires consideration of the surrounding neighborhood. While there is no single optimum ratio between these measurements, for commercial districts best practices call for a ratio of 0.5 to 1.0. That is, at a ratio of 1.0, the height of a building would be equal to the width of the street it faces; at a ratio of 0.5, the height would be equal to half of the width.

 

In the Laurel District, the paved surface of MacArthur Boulevard is approximately 54 feet wide (including four lanes of traffic and parking on each side). Sidewalks add an additional 9 feet wide on each side, giving a total street width of 72 feet. Applying the ratios described above, this would suggest encouraging buildings between 36 and 72 feet tall.

 

Google Sketchup simulations of MacArthur Boulevard showing increasing building heights, with building height to street width ratios of 0.342, 0.625, and 1.041. Source: Mills Public Policy Program.

 

 

 

 

Skyplane setbacks

This principle can be extended through the use of skyplane setbacks. These setback requirements limit the height of buildings at the edge of the street (or at the back of a property) but can allow taller construction in the interior of a property. By moving the tallest part of a building away from the street, this can avoid the canyon effect.

 

A possible skyplane setback requirement under discussion in Oakland would require buildings above 30 feet to be set back 1 foot for each additional 1 foot of height. This could be accomplished with a sloped roof (at 45 degrees) facing the street or by having each additional 10-foot-tall story of the building begin another 10 feet further back from the street.

 

 

Google Sketchup simulations of skyplane setbacks. In the “stairstep” building at left, every second floor is set back further from the street. Across the street, the building at right shows a 45º sloped roof above the first floor, with windows or balconies inset. Source: Mills Public Policy Program.

Because of the north-south orientation of MacArthur Boulevard in the Laurel District, shadows move across the street over the course of the day. Recognizing that different kinds of businesses may thrive best with either morning or afternoon sun, it may be helpful to specify different skyplane setbacks and other design features for

 

Floor:Area Ratio

Oakland’s previous zoning ordinances have specified maximum heights for buildings in most zones. In the current zoning update process, the City is considering replacing these height limitations with a Floor:Area Ratio limit. This limit gives more flexibility in designing buildings with increased density while preserving open space.

The Floor:Area Ratio (FAR) is calculated as the area of all floors of a building divided by the area of the parcel. A one-story building that fills its entire lot would have a Floor:Area Ratio of 1.0. A four-story building that covers only one-quarter of its entire lot would also have a Floor:Area Ratio of 1.0, as shown in the example at right. While the FAR approach does not entail an absolute limit on the height of a building, other constraints limit how tall buildings are likely to be. A 100-story building that only occupies 1/100^th of the lot area would be permitted under a 1.0 FAR limit, but would likely not be an economically feasible choice for a developer.

 

In practice, setback requirements limit the amount of a lot that can be covered. Current zoning requires that buildings be set back 15 feet from their back lot line to allow for service access and to avoid overshadowing the adjacent neighborhood. Skyplane setbacks (described above) could also limit the height of buildings at the front lot line by requiring that higher floors be set back from the street.

 

Here is an example based on a typical Laurel District lot measuring 40 feet along the street and 70 feet deep, with a 15 foot rear setback and a skyplane setback above the second floor.

Total lot size	40 × 70	2,800 ft2	FAR:
First floor buildable area	40 × 55 (reduced by rear setback)	2,200	2,200 ÷ 2,800 = 0.785
Second floor buildable area	40 × 55 (same as first floor)	2,200	4,400 ÷ 2,800 = 1.570
Third floor buildable area	40 × 45 (reduced by skyplane setback)	1,800	6,200 ÷ 2,800 = 2.210
Fourth floor buildable area	40 × 35 (reduced by skyplane setback)	1,400	7,600 ÷ 2,800 = 2.710
Fifth floor buildable area	40 × 25 (reduced by skyplane setback)	1,000	8,600 ÷ 2,800 = 3.070
Sixth floor buildable area	40 × 15 (reduced by skyplane setback)	0,600	9,200 ÷ 2,800 = 3.280

 

Note that the skyplane setback requirement effectively limits the maximum height of the building, since there is less floor area allowed as the building gets taller. In this example, a seventh floor could only be five feet wide (and probably not economical to build), as the 15 foot width of the sixth floor would reduced by 10 feet; an eighth floor would not be allowed.

 

The largest lots on MacArthur Boulevard reach about 170 feet in depth. On such a lot, a six-story building would have an FAR of about 4.75, and an eight-story building would exceed an FAR of 6.0. Note that because setbacks here apply to the fronts and backs of lots, not to the sides, these calculations are not affected by the width of a lot. Because the largest lots fall on the west side of MacArthur Boulevard, taller buildings on that side have the potential to block afternoon sunlight from the street, so additional height limitations may be appropriate.

The Visual Preference Survey

A Visual Preference Survey is a participatory exercise in which workshop participants are asked to respond positively or negatively to photographs of different landscape and architectural features. In this workshop, the exercise was used to help participants envision what they would or would not like to see in the Laurel District under future zoning scenarios.

 

The approach used at the workshop built on techniques developed by A. Nelessen Associates of Princeton, New Jersey for the Portland, Oregon regional government in the early 1990s. Mills students contributed over one hundred photographs from around the Bay Area and beyond to illustrate different aspects of “streetscapes,” including buildings, landscaping, sidewalks, and pavement. Large photographs were placed around the workshop room. Every participant was given 20 colored stickers to place on the photographs: red to indicate examples that participants would not want to see in the Laurel District, or green to indicate examples that they favored. Participants could distribute their stickers however they liked—putting more than one sticker on a photo about which they had strong feelings, or putting no stickers on photos about which they were ambivalent. Mills students took notes on the reasons participants gave for placing stickers as they did.

 

At the onset, participants were reminded that they should not just compare the photos with the appearance of the Laurel District in its current form. Under existing zoning rules, the current 1-story buildings that occupy most of MacArthur Boulevard in the Laurel District can already be replaced with buildings of up to 3 stories. An important point of this exercise was to see how that kind of development, or other kinds of development that might be guided by changes in the zoning ordinance, could be guided to reflect the aesthetic priorities of the Laurel District community. The most and least favored photos are shown on the following pages. After participants placed their stickers, the following themes emerged:

 

Positive Design Aspects

·      Traditional architecture with brick, wood, slate, and stone, focusing on details like cornices, arches, and detailing around windows and doors, was seen as charming, warm, inviting and homey. Details that added to accessibility, transparency, varied design features, art, and awnings all rated extremely well.

·      Landscaping with foliage, flowers, and open space was encouraged, with sidewalk eating and seating areas, balconies, or roofs as open space to promote a balance of indoor and outdoor space.

·      For sidewalks, participants favored greenery, wider sidewalks, seating, brick or cobblestone, and the use of setbacks.

·      Regarding building design and bulk, participants chose examples with varied textures, shapes, curves, angles, colors, lots of windows, a mix of different facades, heights, and levels. Building setbacks, upper floor setbacks, skyplane setbacks, higher ground floors, and 3 to 5 story buildings all were positively viewed.

·      Multiple-use buildings were rated highly.

·      Preserving area character through the use of traditional signage for businesses, corner treatments,

 

“Like corner treatment, architectural detail of façade, outdoor spaces.”

 

“Pedestrian-oriented space, trees.”

“Classic signs, local character.”

 

“Charming, transparent and inviting, wood/brick textures and greenery.”

“Sidewalk café, vibrant.”

 

“Local favorite.”

Negative Design Aspects

·      Negative responses were associated with buildings that were described as dense, heavy, flat, boring, bland, cheap, boxy, suburban, cold, or dated.

·      Design flaws cited included buildings with no businesses on the ground floor; ground floor used only for parking, not enough sidewalk space; lack of color, interesting details, height variations; poor or unattractive construction materials; monotonous windows; and a too short ground floor.

·      Other things that rated negatively were overly modern looking buildings; buildings that were visually too large, seen as unfriendly and industrial; and buildings without a uniform design, a hodge-podge of too much detail making the building appear busy.

·      Buildings were also described as not being pedestrian friendly, with narrow undeveloped sidewalks and few if any ground floor windows or businesses, gates or bars over windows and doors, and overly square or rigid architecture.

·      Concern was raised about the possible effects of freeway noise echoing off building facings, especially with the proximity of Interstate 580 to the Laurel District.

 

 

“Uninviting, industrial.”

 

“Undesirable scale.”

 

 

 

“Not for us.”

 

“Out of character with neighborhood.”

 

 

 

“Looks cold, colors do not contrast.”

 

Workshop Feedback

The workshop concluded with a poll of participants concerning the usefulness of this meeting and inviting suggestions for future workshop topics. Responses are summarized here (rated by number of participants mentioning each aspect).

What was the most useful thing presented this evening?	Rating
Visual Preference Survey	10
Introductions by multiple presenters	4
FAR demonstration (with blocks)	3
Height:Width ratio	2
Shadow studies	2
Clear definitions of zoning	1
Interactive discussion	1
Oakland zoning update process	1
Skyplane setbacks	1
Specific Plans	1
Spirit of working together	1
Using lay terms	1
How could the presentation on tonight’s topic have been more useful to you?	Rating
Larger/more visuals for FAR, Height:Width ratios	2
More detail (but difficult in this time/venue)	2
More time for questions/discussion	2
Consider backs of buildings (neighborhood side)	1
Construct model of existing street (2+ blocks)	1
Less superficial	1
More graphics of Laurel District	1
Plot plan of neighborhood	1
Venue too noisy (refrigerator)	1

 

What other topics related to planning and zoning would you like to see covered in future educational sessions?	Rating
Parking (quantity, aesthetics)	7
Economics of development	4
Examples of other successful communities	3
Public space, plazas	3
Traffic	3
Access to process for community, non-professionals	1
Charette	1
Developing design guidelines (from VPS)	1
Funding options	1
Green/sustainable development	1
Historical preservation	1
How to make sure Laurel is an exception	1
How zoning affects development attractiveness	1
Infill housing options and effects on neighborhood	1
Pedestrian flow	1
Public art	1
Security & public safety	1
Specific opportunities on MacArthur Corridor	1
Specific Transit Plans, BRT?	1
Undeveloped lots: short-, medium-, long-term options	1
Variety of heights	1

 

 

 

Acknowledgements

The workshop was convened by Ada Chan, Executive Director of the Laurel District Association, in cooperation with Mark Henderson, Visiting Assistant Professor of Public Policy at Mills College. We are especially grateful to the Laurel Café for hosting this event and to over 20 members of the community who gave of their time on a chilly holiday evening to participate and contribute. The workshop was led by graduate students from the Mills Public Policy Program, including:

MPP Class of 2009 Nicole M. Hudley Katherine M. Puliafico Drennen T. Shelton Mailee C. Wang

MPP Class of 2010 Alexa L. Benedetti Natasha J. Middleton Ayela F. Mujeeb Sarah D. Rosendahl

For further information about this workshop, or to obtain additional copies of this summary, please contact:

Mills College Public Policy Program

http://www.mills.edu/publicpolicy

Professor Carol Chetkovich, Program Director

 

Professor Mark Henderson, Instructor for PPOL 227

mhenderson@mills.edu

(510) 430-3169