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Credit originated in LEED-ND
This credit originated in the LEED for Neighborhood Development rating system, but the Location and Planning Technical Advisory Group (LP TAGLEED Technical Advisory Group (TAG): Subcommittees that consist of industry experts who assist in developing credit interpretations and technical improvements to the LEED system.) has modified it to fit within the building design and construction (BD&C) rating systems. The LP TAG has added it to the BD&C rating systems because they previously did not address the walkable environment on the project site and therefore did not incentivize high quality design for pedestrians and bicyclists. The LEED-ND version has been modified to remove the LEED-ND requirements that are inappropriate for single-building projects and to revise those need-ing different metrics or thresholds for single-building projects. The credit’s intent, however, largely mimics that of the LEED-ND version: to promote non-motorized transportation by designing safe and pleasant environments for pedestrians and bicyclists. The building-specific version of this credit is further intended to incentivize catalytic projects, whereby single buildings improve the walkability on the project site and motivate walkability improvements on surrounding sites.
Credit Submittals
General
- Register for Pilot Credit(s) here.
- Register a username at LEEDuser.com and participate in an online forum
- Submit feedback survey; supply PDF of your survey/confirmation of completion with credit documentation
Credit Specific:
- A site plan that locates:
- The LEED project boundary
- All principal functional entries
- All sidewalks (with typical dimensions shown), streets, alleys, non-motorized rights of way
- All public spaces, including squares, parks, paseos, and plazas
- All off-street surface parking lots, driveways, garage and service bayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession. openings
- The street frontage that does and does not qualify for the building-height-to-street-width ratio requirements and the corresponding measurements for each frontage.
- The blank walls per façade and the lengths of each blank wall
- All driveway crossings and their widths)
- All street tree locations and dimensioned intervals between street trees
- If the project is a historic building, one or more documents confirming the desig-nation status of the historic building. Acceptable documents may be from the Na-tional Park Service, the State Historic Preservation Office, or local body and in-clude: a public notice such as the Federal Register, a screen capture of a webpage, or another document from one of those bodies.
Additional Questions
- Is this credit the best method to incentivize the inclusion of walkability features on a single-building project, or is another LEED credit strategy better?
- Do the credit requirements provide the right balance between requiring essential walkability features and providing an assortment of additional, optional features?
- Are the requirements overly prescriptive, or do they allow a sufficient level of flex-ibility to create project-appropriate walkability features?
USGBC
Excerpted from LEED 2009 for Core and Shell Development
COPYRIGHT © 2009 BY THE U.S. GREEN BUILDING COUNCIL, INC. ALL RIGHTS RESERVEDSS Pilot Credit 14: Walkable project site
Intent
To promote walking, biking, and other non-motorized transportation that results in reduced vehicle miles traveled (VMTVehicle Miles Traveled (VMT): The number of miles traveled by motor vehicles in a specified period of time, such as a day or a year, by a number of motorists in absolute or per capita terms.), increased public health, and enhanced community participation.
Requirements
Design and build the project to achieve all of the following features:
- A principal functional entryAn entryway that is designed to be used by pedestrians and is open during regular business hours. This does not include any door that is exclusively designated as an emergency exit, or a garage door that is not designed as an entrance for pedestrians. on the front façade faces a public space, such as a street,1square, park, paseo,2
or plaza, but not a parking lot, and is connected to sidewalks or equivalent provisions for walking.- A historic building3is exempt if its historic principal functional entry does not face a public space and/or the entry is not connected to sidewalks or equivalent provisions for walking, and the building cannot be modified without altering key historic features of the building.
- All street frontages have a minimum building-height-to-street centerline ratio of 1:1.5 (i.e. a minimum of 1 foot/300 millimeters of building height for every 1.5
feet/450 millimeters width from street centerline to building façade), measured to the centerline of the street.- Non-motorized rights-of-way may be counted toward the requirement, but frontages facing those rights-of-way must have a minimum 1:0.5 ratio of building height to street width.
- Building height is measured to eaves or the top of the roof for a flat-roof structure, and street centerline is measured from the façade. For building frontages with multiple heights or widths, use average heights or widths weighted by each segment’s linear share of the total block length.
- Alleys4and driveways are excluded.
- A historic building is exempt from these requirements if its dimensions do not meet the ratio requirements.
- Any new off-street parking lots are located at the side or rear of the building.
- Continuous sidewalks or equivalent all-weather route for walking on the project site serve all building entrances and connect them with public sidewalks. Newly constructed sidewalks must be at least 8 feet (2.5 meters) wide on retail or mixed-use blocks and at least 4 feet (1.2 meters) wide on all other blocks. Equivalent provisions for walking include woonerfs5and all-weather-surface footpaths. Alleys and driveways are excluded from these calculations.
- No more than 20% of the street frontage of the project is faced directly by garage and service bayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession. openings. Alley access is used instead, if available.
- If a façade extends along a sidewalk, no more than 40% of its length or 50 feet(15 meters), whichever is less, is blank (without doors or windows).
- At-grade crossings with driveways account for no more than 10% of the length of sidewalks within the project
- Street trees are provided between the vehicle travel way and walkway at intervals averaging no more than 40 feet (12 meters) (excluding driveways and utility
vaults).
- 1a dedicated right-of-way that can accommodate one or more modes of travel, excluding alleys and paseos. A street is suitable for primary entrances and provides access to the front and/or sides of buildings and lots. A street may be privately owned as long as it is deeded in perpetuity for general public usePublic or public use applies to all buildings, structures, or uses that are not defined as private or private use.. A street must be an addressable thoroughfare (for mail purposes) under the standards of the applicable regulating authority.
- 2a publicly accessible pedestrian path, at least 4 feet wide and no more than 12 feet wide, that provides shortcuts between buildings and through the block, connecting street frontages to rear parking areas, midblock courtyards, alleys, or other streets. A paseo may be roofed for up to 50% of its length and may be privately owned or publicly dedicated.
- 3a building or structure listed or determined to be eligible as a historic structure or building or structure or as a contributing building or structure in a designated historic district, due to its historic, architectural, engineering, archeological, or cultural significance. The building or structure must be designated as historic by a local historic preservation review board or similar body, be listed in a state register of historic places, be listed in the National Register of Historic Places, or have been determined eligible for listing in the National Register.
- 4a publicly accessible right-of-way, generally located midblock, that can accommodate slow-speed motor vehicles, as well as bicycles and pedestrians. An alley provides access to the side or rear of abutting properties for loading, parking, and other service functions, minimizing the need for these functions to be located along streets. It may be publicly dedicated or privately owned and deeded in perpetuity for general public use.
- 5a street, also known as a home zone, shared zone, or living street, where pedestrians have priority over vehicles and the posted speed limit is no greater than 10 miles per hour. Physical elements within the roadway, such as shared surfaces, plantings, street furniture, parking, and play areas, slow traffic and invite pedestrians to use the entire right-of-way.
Potential Technologies & Strategies
- A principal functional entryAn entryway that is designed to be used by pedestrians and is open during regular business hours. This does not include any door that is exclusively designated as an emergency exit, or a garage door that is not designed as an entrance for pedestrians. on the front façade faces a public space, such as a street,1square, park, paseo,2
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC.
45 Comments
Historic Building Project
Our project is a major renovation of a historic building in a historic distric. Does uploading National Park Service documentation stating the status os the historic building meet the credit specific requirements?
Hi Pamela. Yes, NPS documentation sufficiently meets the documentation requirements to prove that it is a historic building.
Would a site plan locating the 9 requirements have to be uploaded also?
Yes, you will need to provide a site plan that indicates the location and dimension of the required elements, except for those from which the project might be exempt because of its historic status (the principal functional entryAn entryway that is designed to be used by pedestrians and is open during regular business hours. This does not include any door that is exclusively designated as an emergency exit, or a garage door that is not designed as an entrance for pedestrians. and building-height-to-street centerline ratio requirements).
Building Height Requirements
I agree with Andrew about the building height requirements for this credit. It is the one area that may need to be looked at further. It is true that developing a street frontage is a good design idea, it may not always be applicable in certain places. New York City versas a small town have very different scales which would be appropriate for each, both could be very walkable, both could create a nice relationship with the street. I don't know the complete answer, but I feel it is something we should look into further.
Yes, the building height requirements seem to conflict with the intent of the credit to provide walkable streets. It does not seem to relate to urban fabric project sites. This needs to be modified in subsequent versions of the pilot credit.
I'd agree with both Andrew and Richard and I'll offer the following potential strategy for improving this credit: Perhaps the proportional requirement between building height and distance of building from the center of the street can be based on the surrounding density of the area. For example, in lower density areas, perhaps the ratio could drop to 1:2. Inversely, for higher density areas the proportions could be increased to 1:1. The density of the surrounding area of a project could be determined similarly to how it is determined in SS credit 2, Development Density & Community Connectivity.
Non-Motorized Right-of-Way
Two items:
1) A clarification of the language on non-motorized rights-of-way guidance.
2) A question whether the minimum height ratio is an appropriate measure of walkability in campus settings.
1) We are applying the pilot credit in a campus setting, where many of our projects front walks and greens, as opposed to streets. I assume then, for the purposes of buiding height ratios, that we should treat a walk that crosses parallel to the facade of the building as a non-motorized right-of-way.
The non-motorized ROW guidance requires "a minimum 1:0.5 ratio of building height to street width." Although the "street width" term is used, which might imply the sidewalk width, I take it that this ratio should instead refer to the distance from the walk centerline to the facade of the building. This would be consistent with the motorized street calculation method.
2) While our project satisfies this minimum 1:0.5 requirement, I would expect that there are many existing buildings in campus settings that will not satisfy this requirement. In the case of a 10' walk placed 30' from the facade, the minimum height ratio would require a 70'+ building. Yet many observers are likely to consider a four-story campus building as described above to be very walkable. I wonder if the building height ratio is an appropriate requirement for walkability for projects in campus settings.
Hi Andrew,
To answer your questions in order:
1. You've correctly assumed that you should tree the walkway that's parallel to the facade as a non-motorized right-of-way.
2. I appreciate your insight on walkability in the campus context. The distance between buildings and the minimized presence of traditional ROWs on (most/some) campuses might necessitate different metrics.
Please note that - for the requirement to which you've referenced - the language should actually read "1:0.5 ratio of building height to street centerline distance." This will change the needed height of your building, and I hope that this brings it more in alignment with its surrounding context.
Existing sidewalk inclusion?
Hi,
I would like to attempt this credit for several of my current and future LEED projects. I am trying to determine the following:
There are existing sidewalks within the LEED boundary that are not being changed. They are immediately adjacent to the bordering streets. Since they are not in the scope to alter, we cannot move them in order to have trees between the sidewalk and vehicle travel way.
Can we exclude the existing sidewalks from the tree requirement since we cannot change them? Obviously, any new sidewalks would meet the requirement. I ask b/c only "newly constructed" sidewalks are required to meet the width criteria of the credit, but it does not specifically address it for the trees...
Help?
No one? I'd like to consider this credit for at least 6 different projects right now, and the answer kinda affects all of them...
Hi Emily, I'm sorry for the delayed reply. We've actually been discussing it internally for the past few weeks. Regardless, I should have at least acknowledged reading your post...
In short, we've concluded that the street trees requirement applies to both new and existing sidewalks. We say so for two reasons:
1. The continuous sidewalk requirements earlier in the credit have new sidewalk-specific requirement. But existing sidewalks can/must also meet the requirements, provided that they’re continuous and serve all building entrances. So, there’s an implied intent that existing sidewalks are held to some sort of requirements throughout, including the addition of street trees.
2. Street trees are very, very important to the pedestrian experience, and we want to ensure that a credit-worthy walkable project site has them.
We'll soon update the pilot credit language to reflect this decision.
I am currently working on an urban infill project with retail at the ground floor and apartments above. We meet all the requirements for the walkable project site and provide adequate street trees. Our building site differs from yours, Emily, in that the sidewalks will be replaced to accommodate updated city zoning policy but with that said, the street tree locations are also designated by the policy which creates a spacing of 42'-0" versus the required 40'-0".
I have been researching others past comments regarding street trees and have not seen this brought up. I am assuming that there is a variance given for the spacing and that the tree canopy will eventually create the required aesthetic this credit is pursuing - can someone please clarify if this has been discussed previously?
Thank you!
Updated question:
The credit language now states the following:
"Street trees are provided between the vehicle travel way and walkway at intervals of no more than 450 feet (15 meters) (The width of driveways, utility
vaults and alleyways intersecting the vehicle travel way or walkway may be excluded from these calculations)."
^ That is copied/pasted directly from the credit page. Can you verify that 450 feet is a typo? I'm assuming the requirements didn't change THAT much from a few months ago...also, 15 meters definitely does not equal 450 feet; it's 49.21 feet. Please clarify. Thanks.
Unusual circumstances
We are considering using this pilot credit in order to demonstrate siting a project in order to take advantage of the walkability of the project itself and put less emphasis on the parking lots designed for it will make an impact on human behavior. The project is a National Wildlife Refuge and is, therefore, outside of a neighborhood, but is highly oriented for pedestrian and bicycle traffic. Does anyone have input on whether or not a project such as this can contribute in theory to the focus of this pilot credit? Thank you!
I believe that - even with your project's surroundings - it still can safely pursue earning this pilot credit. Remember that this BD&C pilot credit focuses entirely on what a single-building project can do on the project site and not necessarily what is needed of its broader surroundings. You desire to minimize the prominence of parking lots is well-aligned with the credit intent. So I recommend attempting to earn the credit!
Facade along the Sidewalk
I am looking for guidance on the following credit requirement:
“If a façade extends along a sidewalk, no more than 40% of its length or 50 feet (15 meters), whichever is less, is blank (without doors or windows).”
A portion of the building is set back about 18’ from the centerline of the sidewalk. The 80’ long façade does not have any windows, but is a ‘green wall’ covered in vegetation. The rest of the building is set back about 75’ from the centerline of the sidewalk and contains the required amount of windows.
Is this facade considered to extend along the sidewalk? Or, is it not of concern since it is not directly adjacent to the sidewalk?
Hi Candace. While a specific distance hasn't been specified to define "along a sidewalk," the portion of the building 18' from the centerline of the sidewalk is most likely to be counted as the facade extending along the sidewalk. However, landscaping/vegetation has traditionally not counted towards achieving the requirement, at least not in LEED-ND 2009 (NPDc1: Walkable Streets). Since the BD&C pilot credit is largely based on NPDc1, the green wall will likely not meet the requirements here. Therefore, I encourage you to incorporate doors and windows to the fullest extent possible.
Chris, would any of the internal discussions impact my July 17 question listed above? Due to the program in the building, windows and doors are not feasible.
Hi Candace, I'm sorry for the delayed reply. When attempting to earn this credit, you might be able to describe the special circumstances for why windows and doors aren't feasible. However, those of us who developed the pilot credit believe that doors and windows are a part of the complete package that a building needs to provide in order to have a walkable project site. Therefore, programming that prevents doors and windows would make the building ineligible for the credit.
Safe pedestrian access to the building please!
I would like to see this credit evolve to include pedestrian access to the building. Most cities in my country are very pedestrian oriented and can comply with this credit´s requirements. However a problem that I have discovered is that sometimes pedestrian crossings are badly located or non-existing. So I would like the safe walking path to near amenities and public transport to be included into this credit. Having windows, sidewalks and no parking lots is not a problem for us.
Thanks, Maria, this is very helpful feedback. WIth respect to safe walking paths to amenities and transit, rest assured that - in actuality - the proposed "walking distance" definition for LEED 2012 already stipulates that such paths be safe and include (among other things) cross walks. That definition is in the 4th Public Comment period glossary and can be downloaded here: https://www.usgbc.org/ShowFile.aspx?DocumentID=18949
Walkable Streets - Historic
Our project is an adaptive reuseAdapted reuse is the renovation of a space for a purpose different from the original. of a historic building in a historic district. Walkability is key since it is a hotel with no parking in a neighborhood which supports walking for business, pleasure, residential and tourism. Our design meets all the credit requirements except length of blank walls per facade. Given the historic nature of the building, we cannot modify the facade to meet the criteria. Any suggestions ??
The Walkable Streets Prerequisite requirements in the latest draft of LEED-ND 2012 allows a few exemptions for projects in historic districts; however, the requirement regarding maximum blank facade area is found in the Walkable Streets Credit, under which there are no exemptions listed for projects in historic districts. I suggest that you submit a project-specific Credit Interpretation Request to determine if your project conditions warrant an exemption from this requirement.
Service Bay Entries
The architect of our project created a design where there is no "back" of the building - the street-side elevation is nearly identical to the rear (parking lot and service side). So the first floor is full height aluminum storefront all around the building.
Potential retail tenants on the first floor have started to creatively figure out how they will receive deliveries and get rid of their trash through the same appearing glass entries located on the back that the public users on the other side (street side) of the building will use. In addition, they are figuring out how they keep the back of house functions from being visible from the outside.
In relation to the requirement regarding length between service bayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession. entries, does anyone think that the described service entrances actually qualify as the service entrances? Or do they strictly mean curb cuts/overhead doors/etc for loading dock entrances?
Hi Anthony. I believe that the service entries you describe do not count as the service bayA bay is a component of a standard, rectilinear building design. It is the open area defined by a building element such as columns or a window. Typically, there are multiple identical bays in succession. entries the pilot credit is trying to minimize. In alignment with what you suggested in your second question, the requirement is truly meant to limit traditional, large-scale service entries that require large curb cuts, driveways, and other interruptions to the pedestrian environment. So, I think you're safe with the current building design.
Upcoming Pilot Credit Webinar
USGBC will be hosting a webinar on location- and transportation-related pilot credits on Thursday, March 22, 1:00 - 2:30 ETEvapotranspiration (ET) is the loss of water by evaporation from the soil and by transpiration from plants. It is expressed in millimeters per unit of time..
For more information visit: http://usgbc.peachnewmedia.com/store/seminar/seminar.php?seminar=10516
The webinar will be registered for 1.5 hours of LEED Specific (BD+C, ID+C, O+M, HOMES, ND) GBCI hours as well as 1.5 AIA/CES LU/HSW/SD hours.
Main Entry facing a Plaza
Our project is a dormitory for 1-8 grade kids located in a campus. The main entry faces a plaza, second entry faces a parking cul-de-sac (entry faces the street with parking inside the cul-de-sac) and third entry faces a play area. We have sidewalks all around the building and connecting to other nearby buildings but there is'nt a public sidewalk in this campus setting to connect to.
Is it okay as long as we can show connection to near by buildings and how pedestrian-friendly it is?
Do we need to measure the building-height-to-street ratio for the second entry?
Appreciate your response.
Cumulative Facade Intrusion?
Our project has two facades extending along sidewalks. Going by the credit requirements, we cannot have more than fifty feet of blank facade. One of the facades has 54 feet of blank length, while the other has only 33 feet of blank length. Is it possible to use a cumulative approach, or a 'blank facade budget' methodology to achieve this credit?
Alternatively, would glass art enclosures or murals count as non-blank facade? We have some lengths of the facade that cannot have an opening such as a door or window due to the structural integrity of the high-rise building.
For your first question, projects cannot use a cumulative approach to address your buildings facades. Each, separate facade that faces a sidewalk must be individually assessed to determine how much can't be blank. For the 54-foot blank wall, no more than 21.6 total feet can be blank; for the 33-foot blank wall, no more than 13.2 feet can be blank.
Second, doors and windows are truly the only design feature that count towards reducing the amount of blank wall space. Murals and glass-enclosed art are excluded in LEED-ND 2009 and are as well in this pilot credit.
Sidewalk definition
How would the sidewalk length for the category "Sidewalk Intrusions" be measured for a project consisting of several buildings on a plaza.
There are no defined sidewalks and nor driveways on the plaza (all hardscapeHardscape consists of the inanimate elements of the building landscaping. Examples include pavement, roadways, stone walls, concrete paths and sidewalks, and concrete, brick, and tile patios.).
I would assume one sidewalk at the project boundary and one between each building.
On the whole, you need to be careful to have common terminology for project features across all submitted credits. Meaning, if it is a plaza, you should not call it a sidewalk for the purposes of a different credit (i.e. this pilot credit). Because you have indicated that the plaza does not have defined sidewalks, it would therefore not contribute towards compliance with the sidewalk intrusions requirement.
Entrance lobby as live-work space
In my project there is a main entrance lobby that includes a permanently manned reception. Would that count as live-work space for category "Ground-Level Use and Parking" option h?
I am not quite sure as it would probably be 2-3 persons on several hundred square meters which is not really comparable to an office or shop.
Hi Jens. You're correct in that the permanently manned reception would not count as live-work space, as the people that work in that space do not also live in that space.
More importantly, I need to note that the updated version of this playbook (posted to the Pilot Credit Library in conjunction with the start of LEED 2012 2nd Public Comment) no longer includes this optional requirement. You may download the updated version here: http://www.usgbc.org/ShowFile.aspx?DocumentID=8189.
Maps
The credit asks for multiple types of map to show different site requirements. Is it acceptable to include all necessary info on one map, or do they have to be broken down like they are under the "Credit Specific" requirements?
Hi Jacki,
You are welcome to document your project details on one map. I'll specifically recommend, however, that you clearly label each detail that fulfills the pursued parts of the credit. Of course, if you believe that one map will condense the information too much (and make it difficult to understand), you're welcome to distribute the information across two or more maps.
On-Street Parking
Can projects use on-street parking that has time limitations (e.g. Parking is prohibited from 8am-6pm on Weekdays)? Since parking is technically allowed, just not at all times, can this still count towards the credit?
Hi Carly,
Yes, on-street parking that has some time limitations can still count towards the credit. The intention of this requirement is to encourage this type of parking the buffers pedestrians from auto traffic. The space that remains even during that prohibition helps to accomplish that goal.
What is the correct way to find the width of the street?
The credit requirements do not seem to be consistent in defining the street width. First they require a minimum building-height-to-street width ratio of 1:3, "measured to the centerline of the street." A bullet point directly underneath this statement says that "street width is measured facade to facade."
Should I measure from the facade of the project building to the facade of the building across the street? Or, should I measure from the facade of the project building to the centerline of the street, and do I multiply this number by 2? If anyone can shed some light on this confusing issue I would greatly appreciate it. Thanks!
Sorry for the confusion, Grace. You need to adhere to the first part that you quoted: having a BH:SW ratio of 1:3, measured to the centerline of the street. Width is determined from facade to street centerline.
You should not measure facade of the project to the facade of the building across the street. You should measure from the facade of the project building to the centerline of the street, but do not multiply this number by 2. I hope this helps!
Chris, if you have two rows of trees in the middle of the street and two lanes in each direction on each side of the trees, what is the centerline here? From the building to the edge of the tree line? Or from the building to the middle of the tree line, between the trees? Thanks!
Estimated crown diameter
Does anyone have a good resource for or way of calculating a tree's estimated crown diameter? (Benchmark "m" for NC/CS or "f" for Schools). Thanks!
Hi Christina,
As of now, there is no one guide or calculation, that I'm aware of, that applies to all trees. It really depends on species and growing conditions, which vary greatly.
However, some local jurisdictions give estimated crown size information in their landscape ordinance. As an example, I will point you to one local public facilities manual that lists some example species and their projected size at 10 years (Fairfax County, VA, page 57, Table 12.19): http://www.fairfaxcounty.gov/dpwes/publications/pfm/chapter12.pdf
Many online horticultural resources also provide information on species size (at maturity) in good growing conditions (http://plants.usda.gov/ for example).
Another possible approach is to calculate the DBH of the tree at installation, and then project the DBH at 10 years. DBH is related to crown size based on species, and this would give you an idea of how big the tree could get.
Landscape architects (and arborists) are good resources, and they should be able to help you with this as well.
These methods listed above will yield rough calculations of size, as it depends on the specific tree, growing medium, growing conditions, etc. But I don't think you need to get TOO detailed for this.
Thank you-
Theresa
I'm a little confused about the defination of street frontage. Normally, not all projects facades are designed along with street, how can I measure the length of "street frontage" and "the width from facade to centerline"?
The width from the facade to centerline will various, am I right? Thanks in advvanced your kindly response.
If the building is not parallel to the street, you need to find the average setback distance and measure that to the centerline. As you've likely read above, this credit originated in LEED-ND. Its reference guide is especially helpful for these and other calculations, so you might want to get a copy if you anticipate using this or other ND-originated credits in the future.
Let us know if this helps or if you need more clarification.
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