Sidewalk paving can consist of traditional paving materials such as concrete or asphalt or non-traditional materials used as accents or in key locations. Special paving treatments can enhance the aesthetics of public spaces in a city, give circulation areas a stronger sense of place, and enhance the hierarchy of public spaces. Special paving treatments can be selected from a range of options, including natural stone pavers, unit concrete pavers, bricks, textured and colored concrete, stamped asphalt, and concrete with exposed or special aggregate or other finish treatments.

Special paving can be a functional stormwater amenity as well as an aesthetic enhancement, when designed as permeable paving. Permeable unit concrete pavers can provide both function and aesthetic appeal. Permeable asphalt and concrete change the surface function but do not greatly enhance the overall aesthetics of the site.

See Permeable Paving.

Process Overview

A Special Sidewalk Surface Permit grants permission to replace standard concrete sidewalk with alternative paving materials, including permeable paving. A permit is required to ensure that sidewalk paving is properly constructed and maintained in order to maximize environmental benefits, protect public safety and limit conflicts with infrastructure.

Special Sidewalk Surface Permit

See Permit Process for more information

Official Codes & Documents

• Better Streets Plan (street design guidelines)
• ADAAG (Accessibility Standards)

Design Guidelines

Location

Street types: Commercial Throughway, Downtown Commercial; Neighborhood Commercial; Mixed use; Boulevard; Alley; Shared Public Way; Paseo

Sidewalk zones: Frontage; Throughway; Furnishings; Edge; Extension; Parking lane; Full roadway (alleys and paseos)

Sidewalks should use standard scored concrete paving at a minimum. In addition, special paving may be included as a component of any street type. Special paving is most appropriate on downtown, commercial, ceremonial, and other special streets or small streets. Specifically, special paving should be considered in:

• Transit stop areas, including transit curb extensions and medians
• Pedestrian crossings, especially at important civic locations, neighborhood commercial areas, and other special districts
• Mid-block and raised pedestrian crossings
• Pedestrian refuge areas within medians
• The full right-of-way of shared public ways
• Local access lanes of multi-way boulevards
• Pedestrian-only streets, including transit malls, pedestrian malls, and areas that are regularly but temporarily closed to vehicle traffic
• Flexible space in parking lanes
• Street and sidewalk parks
• Curb extensions
• The furnishings zone of sidewalks
• Driveways
• Gateways and other special places

Design

Paving type

Standard Paving

Standard sidewalks should use concrete scored in 3’ x 3’ squares.

Downtown sidewalks should use concrete mix to the specifications of the Downtown Streetscape Plan.

Special Paving

Pavers consist of sand set pavers, mortar set pavers, and permeable or porous pavers over clean drain aggregate. Special pavers include natural stone pavers, unit concrete pavers, unit concrete permeable pavers, textured and colored concrete, stamped asphalt, concrete with exposed or special aggregate, and other finish treatments.

Special aggregates, colors, and textures may also be considered. Maintenance cost of special pavers should be considered during the selection process.

When non-customary materials are used, they should extend at least a complete block for design consistency and maintenance efficiency. Similarly, non-customary scoring should extend for at least one block. Exceptions can be made where special paving is being used to highlight transit stops, parks, plazas, or other site-specific features.

Accessibility

Special attention should be paid to accessibility and comfort considerations of paving materials in selecting appropriate locations for different paving types. Paving materials must meet all accessibility standards per ADAAG and Title 24. Generally:

• Paving materials should not pose tripping hazards or cause excessive vibration for wheelchairs
• Paving should be designed, installed, and maintained to be smooth and level. Surfaces should not be interrupted by steps or abrupt changes in level of more than 1/4 inch.
• Unit pavers must have gaps of no more than 1/4, beveled to no more than a 1:2 ratio.
• Saw cut joints in poured concrete are preferable to troweled joints
  • Surfaces with a slope of less than 6% gradient should be at least as slip-resistant as what could be described as a medium salted finish. Surfaces with a slope of 6% gradient or more must be slip-resistant. DPW Bureau of Street Use and Mapping (BSM) requires sidewalks to have a minimum coefficient of friction – check with BSM for the value.
  • Surface cross slopes should not exceed 1/4 inch per foot except where, due to topography, it creates an unreasonable hardship, in which case the cross slope may be increased to a maximum of 1/2 inch per foot. Check with BSM for conditions that would allow cross slope to exceed 2%.

Refer to the ADAAG and Title 24 standards for more information.

Curb ramps should be treated in either smooth solid concrete or paving treatment to match adjacent paving. See Curb Ramps.

Installation

Special paving materials should follow these guidelines:

• Select surface materials with low maintenance requirements and high durability, slip-resistance, and compressive strength.
• Retain a certified geotechnical engineer and reference a geotechnical investigation report for soil type and loading capabilities.
• Understand soil type and settlement potential when choosing a paving surface material and sub-base thickness.
• A proper sub-base is as important as the surface material. Use of a recycled sub-base is recommended. Ask suppliers of recycled materials to provide material testing results for loading equal to Caltrans classification standards.
• Understand the loading needs per the expected use (trucks, emergency vehicles, vehicles, pedestrian-only). The paver and sub-base depth should be designed for the heaviest expected loading per City standards. A concrete slab with mortar pavers is recommended in high traffic areas with heavy loading for long-term durability.
• Settlement may be an issue in areas of high clay content or over “Bay Mud”. An enhanced sub-base or concrete slab base is typically required per geotechnical recommendations.
• Follow manufacturer recommendations for maximum slopes and minimum recommended sub-base depth and material.
• Conduct percolation tests or soil science reports if permeable or porous pavers are used. Where infiltration is not feasible, an underdrain may be used.

Layout

Special paving can be implemented as a field treatment, consistent across the entire sidewalk, plaza, or shared space, or can define specific areas within the streetscape. Where implemented as a field treatment, it should be organized in regular or organized artistic patterns.

Special paving at specific locations

Special paving should be considered for installation in the following locations subject to the guidance elaborated in the related sections of this document. Recommendations are summarized below.

Furnishings Zone: Special paving in the furnishings zone can visually separate this space from the rest of the sidewalk, highlighting its function as an area to sit or step out of pedestrian flow. Permeable paving, such as pavers set on a clean aggregate gravel sub-base, should be used where possible to allow stormwater infiltration, water, and oxygen to reach tree roots below.

Pedestrian Crossings: Special paving treatments communicate to individual users that the crosswalk is part of pedestrian space, not an encroachment by pedestrians into the roadway. Paving, texture, and color treatments are especially important in places where it is important to make pedestrians more comfortable crossing.

The application of special paving in crosswalks should consider wear and tear caused by vehicles crossing the paving, and requires additional capital and maintenance funding. The paving should be designed and installed to maintain the desired visual and textural appearance. Special paving is not a substitute for standard or high-visibility retro-reflective crosswalk markings. Standard 12 inch transverse lines should still be used outside a decorative crosswalk treatment to establish a marked crosswalk.

Curb Extensions: Where curb extensions are added, they may be designed as useable pedestrian spaces. Special paving can reinforce this intention by visually separating curb extensions from the adjacent sidewalk, and suggesting that these spaces are meant for sitting and relaxing as opposed to just walking.

Pedestrian Refuge Areas in Medians: Special paving should be considered at pedestrian refuges. The pedestrian path through the median and adjacent areas may include special paving. See Medians and Islands for appropriate dimensions and treatments.

Transit Stops: Special paving treatments should be considered at transit stop locations to define the waiting zone and to clarify connections to transit. Curb extensions and transit boarding islands should be paved with finer-grained paving treatments ranging from unit pavers to special scoring and color in concrete. At transit stop locations where there is no curb extension, distinctive sidewalk treatments such as alternative paving or scoring patterns or an edging treatment in the furnishings zone should be considered.

The sidewalk throughway adjacent to transit stops should be treated similarly to the surrounding sidewalk area to distinguish the transit stop area from the sidewalk throughway zone.

Flexible Space in Parking Lanes: Where parking lanes are re-designed as part of a program of flexible use, special paving should be used to differentiate the parking lane from the adjacent vehicular travel lane and the furnishings zone from the throughway zone. Special paving should be used to designate the outdoor rooms meant for people to sit and relax.

Pocket Parks: Special paving should be considered as an edging treatment around sidewalk pocket parks and planting areas. Travel lanes adjacent to these areas can use special paving to indicate a shared space where pedestrians may cross the street from the sidewalk to the open space. Within such spaces, permeable pavers and other alternative permeable surfaces such as decomposed granite are highly recommended for paths, edging, and other hardscape areas.

Shared Public Ways: On shared public ways, special paving is integral to communicating that the entire right-of-way is a space to be shared between pedestrians and vehicles. Paving patterns and layout should be used to convey the location of spaces within the right-of-way, defining the edges for parking, playing, and sitting, and highlighting the edges of planting areas.

Multi-Way Boulevards: Special paving can be used to communicate the function of the local access lane in boulevards. Special paving should be considered for the entire lane to enhance this function. The change in material identifies a space intended for local circulation and that differs from the through lanes in the center of a multi-way boulevard, particularly in combination with a shared public way treatment or raised crossings.

Paseos (Pedestrian-Only Streets): Where a whole right-of-way is converted to pedestrian space or special mixed transit and pedestrian space, or where frequent temporary closure for pedestrian use is considered, special paving should be used to enhance the space for pedestrians. Special paving should be used to define and highlight spaces within the public right-of-way, breaking the space down into a more pedestrian scale.

Driveways: Driveways outside the path of travel can use interlocking pavers, pervious concrete, and other similar materials to add visual variety to the streetscape, and allow infiltration where appropriate.

Environmentally responsible material choices

Many paving surfaces, sealants, coatings, traffic markings, and other products are composed of materials that are harmful to the natural environment. The type of material selected should consider the level of volatile organic compounds (VOCs) and specify zero- to low- VOC agents. Polycyclic aromatic hydrocarbon (PAH)-free sealants and/or asphalt bases should be considered.

Many paving surfaces are composed of natural materials derived from highly impactful quarrying and processing methods that are damaging to the natural environment. The City should encourage the use of recycled or reclaimed materials. Granite curbs removed during retrofit should be reused, either on-site or on other streetscape projects.

Streetscape projects should strive to use sustainable paving materials, including:

• Materials with recycled content: the sum of postconsumer recycled content plus one-half of the pre-consumer content constitutes at least 20% (based on cost) of the total value of the materials in the project
• Regionally-harvested materials: materials or products that have been extracted, harvested or recovered, as well as manufactured, within 500 miles of the project site for a minimum of 20% (based on cost) of the total materials value
• Rapidly renewable materials: materials and products made from plants that are typically harvested within a ten-year cycle or shorter for 2.5% of the total value of all materials and products used in the project, based on cost.

Maintenance

With some exceptions, fronting property owners are responsible for the on-going maintenance and upkeep of sidewalk paving as well as all sidewalk elements directly fronting their property, such as trees, landscaping, streetscape furnishings and alternative paving materials in the sidewalk. Generally, the City is responsible for maintaining roadway paving and other features in the roadway, such as medians.

Typically, if you initiate street or sidewalk improvements, you will be responsible for maintenance of those features. Specific requirements will be described in your permit.

Projects installing permeable paving materials should be mindful that permeable paving is a functioning element of the stormwater infrastructure and must be maintained to serve its required stormwater function. See Stormwater Overview and Permeable Paving for more information.

For a more detailed description of maintenance responsibilities, see Maintenance.

Top of Page