Commercial Boardwalk Design: ADA Compliance
At PermaTrak, we frequently receive questions concerning boardwalk compliance with the Americans with Disabilities Act (ADA). As a boardwalk designer, I consult the ADA guidelines for horizontal gaps, vertical changes, boardwalk slopes, ramps, railing requirements, etc. on a daily basis. First for some ADA background information -
Specific Requirements of the Americans with Disabilities ActIn 1991 the Department of Justice adopted the Americans with Disabilities Act (ADA) Standards for Accessible Design. These standards required newly constructed and renovated places of public accommodation and commercial use to be designed in ways that prohibited discrimination on the basis of disability. In 2010, the ADA received revised standards concerning accessibility.
2010 ADA Standards for Accessible Design
I thought it would be helpful to summarize the 2010 ADA revised standards related to horizontal gaps, vertical changes, walking surface slopes, railing requirements, etc. for those of us designing ADA compliant boardwalks, pedestrian bridges, and other structures for multi use trails.
I'd also like to post my answers to several common questions specific to PermaTrak and ADA compliance. As a new boardwalk system, these may be the first questions a designer new to PermaTrak may ask us:
- Is the entire PermaTrak system ADA compliant?
- Can PermaTrak's boardwalk system be used on applications where a slope is needed? If so, does it meet ADA requirements?
- What is the max slope you can achieve with a PermaTrak boardwalk?
First, let's be clear on what ADA defines as an accessible route -
Chapter 4 from 2010 ADA Standards for Accessible Design – Accessible Routes
"402.2 Components. Accessible routes shall consist of one or more of the following components: walking surfaces with a running slope not steeper than 1:20, doorways, ramps, curb ramps excluding the flared sides, elevators, and platform lifts."
So, to answer Question #1, "Is PermaTrak's boardwalk system ADA compliant?"
Our system not only meets ADA requirements, but PermaTrak will remain in compliance for years to come. Traditional options for boardwalks (Southern Yellow Pine timber or composite decking options) begin rotting, twisting and decaying immediately after installation - they will require annual maintenance.
Our warranty guarantees that our structure will remain for years to come. As long as the contractor installs the PermaTrak to ADA compliance then our concrete structure will remain compliant. No other boardwalk system provides a warranty on their shape like PermaTrak. The only way to keep Southern Yellow Pine timber or composite decking products in compliance is with costly ongoing maintenance.
ADA Compliant Boardwalk Slopes
The 2010 ADA revisions are pretty minor as they relate to slopes. They allow for an increase in the cross slopes of walking surfaces by raising the maximum to 1:48, whereas it was originally 1:50. The running slope (slope that is parallel to the direction of travel) must not be steeper than 1:20 (5%) for walking surfaces (Section 403.3).
ADA Compliant Boardwalk Ramps
The 2010 ADA Standards for Accessible Design defines a ramp as a "walking surface that has a running slope steeper than 1:20." Section 405.2 says "Ramp runs shall have a running slope not steeper than 1:12."
Question #2: "Can PermaTrak be used where a slope is needed?"
What do these ADA slope and ramp requirements mean for PermaTrak? Typically they will define a PermaTrak boardwalk's elevation profile. The 1:20 running slope for a walking surface or the 1:12 slope for a ramp run required by ADA guidelines are great examples. So yes, PermaTrak concrete boardwalks can be used where a slope is needed while remaining in compliance with ADA guidelines. PermaTrak's engineering team can assist you in designing for any of these conditions up to the max required by code, using our standard concrete boardwalk components.
Question #3: What is the max slope a PermaTrak concrete boardwalk can achieve?
While it is possible to design a PermaTrak concrete boardwalk for more severe slopes than 1:12, the vast majority of the projects we work on are publicly funded projects and must be designed for commercial, public use. The max slope we have designed PermaTrak to thus far has been the 1:12 (8.33%) slope, for a couple of different projects.
The best illustration is shown here in the picture and construction drawing showing the boardwalk profile. This project is located on the campus of Wake Forest University. The PermaTrak application was an elevated sidewalk spanning over protected tree roots. This concrete boardwalk walkway remains within ADA compliance.
More ADA Information for Professional Designers and Owners
While there is no boardwalk or pedestrian bridge-specific version of the 2010 ADA Standards for Accessible Design, the following sections apply to engineer and landscape architect designers for these types of outdoor trail-related hardscape products.
"405.7 Landings: Ramps shall have landings at the top and the bottom of each ramp run.
405.7.2 Width. The landing clear width shall be at least as wide as the widest ramp run leading to the landing.
405.7.3 Length. The landing clear length shall be 60 inches long minimum.
405.7.4 Change in Direction. Ramps that change direction between runs at landings shall have a clear landing 60 inches minimum by 60 inches minimum."
So to summarize ADA compliant landing areas as they relate to boardwalks or pedestian bridges - when the structure is designed for the max slope of 1:12, that section of walkway can extend for up to 30 feet. After 30 feet, the design team is required to include a landing area that complies with the design guidelines above. A good example of this is shown here at the PermaTrak boardwalk and observation deck for Blackwater National Wildlife Refuge in MD. You can see the occassional landing area as the boardwalk increases in height above the wetlands.
Openings: Horizontal Gaps Between Wood Boardwalk Planks or PermaTrak Concrete Treads
Section 302.3 on Openings includes: "Openings in floor or ground surfaces shall not allow passage of a sphere more than 1/2 inch (13 mm) diameter except as allowed in 407.4.3, 409.4.3, 410.4, 810.5.3 and 810.10. Elongated openings shall be placed so that the long dimension is perpendicular to the dominant direction of travel."
For traditional wood or composite decking planks, this guideline means that the gap between deck boards shall be no greater than 1/2''. PermaTrak's concrete boardwalk treads are a bit different because they have a slight draft to allow the precaster to remove them from our steel molds. After installation, the boardwalk or platform area will have a ⅛’’ gap at the bottom of the tread surface (under the boardwalk) and a ⅜’’ gap on the top walking surface. With ⅛’’ gap spacing at the bottom, water drains easily and the owner can avoid the potential buildup of dirt, debris, sand, etc.
In terms of handrails, the 2010 revisions have relaxed requirements. The revised standards only require gripping surfaces to have rounded edges and do not specify a specific edge radius. Additionally, the maximum diameter of handrail gripping surfaces has been increased from 1.5 inch to 2 inches. The 2010 Standards only require handrails to be unobstructed on their top and sides, while the bottom of a gripping surface is required to be unobstructed for at least 20% of its length.
On a boardwalk project with a walking surface slope over 5%, the design team is required to include a grab rail on the railing system. See the picture from Blackwater National Wildlife Refuge in MD as an example.
To allow space for wheelchairs, boardwalks must be at least 3.9 feet wide, although 4.9 feet is ideal since it allows passing space for wheelchair users. If boardwalks longer than 200 feet have less than 4.9 feet width, passing spaces must be provided every 200 feet to make them accessible.
The 2010 ADA Standards for Accessible Design states in Section 403.5.1 - "Except as provided in 403.5.2 and 403.5.3, the clear width of walking surfaces shall be 36 inches minimum."
PermaTrak’s ADA Promise:
We will work closely with the awarded (installing) contractor to ensure that PermaTrak is installed to comply with all ADA regulations. We are invested in the success of the project and we want to ensure maximum usability and enjoyment for everyone. Click to read more on how we dedicate our time (field representative) and resources during concrete boardwalk installations.
I hope this article provides some clarity on PermaTrak concrete boardwalks and ADA compliance, not only for our system but for all boardwalk, pedestrian bridge and trail related structures. Let me know if you have any questions, I'm happy to discuss design guidelines for your project.