An accessible walkway can rise no more than 1 inch for every 20 inches of length (1:20, or 5%), and it can tilt sideways no more than 1 inch for every 48 inches of width (1:48, about 2%). Anything steeper than 1:20 along the direction of travel is treated as a ramp, with its own stricter rules. Those are the numbers in the 2010 ADA Standards for accessible routes, and they decide whether a sidewalk, entry path or brick walkway works for people who use wheelchairs, walkers or canes.
We are masons in Richmond, Virginia, not accessibility consultants. But we repair and build brick walkways, steps and patios across Richmond every season, and slope is where good intentions and real brick meet. This guide gives you the limits, explains how to read them, and shows how a brick walkway can drift out of tolerance over time.
TL;DR
- Running slope (along the path) must not exceed 1:20 (5%). Steeper than that, the surface is a ramp.
- Cross slope (side to side) must not exceed 1:48, written as 2.1% when you measure with a digital level.
- Ramp runs top out at 1:12 (8.33%). Existing sites with tight space can use steeper slopes only in limited, short rises, and nothing steeper than 1:8.
- Slope is only part of the test: width, surface and small level changes matter just as much.
- Brick walkways in Richmond settle, heave and wash out over the years, so a path that was compliant can slip out of tolerance. Check it before you repair it.
Table of Contents
- The numbers at a glance
- Running slope: the 1:20 line
- Cross slope: the 1:48 limit and what 2% means
- How to measure walkway slope
- When a walkway becomes a ramp
- Beyond slope: width, surface and small changes in level
- Public sidewalks versus private walkways
- Why brick walkways drift out of slope
- Brick and lime mortar: what holds a historic walk and its steps together
- Our perspective on slope and brick
- Have a Richmond brick walkway checked
- A planning checklist before you build or repair
- FAQ
- Sources
The numbers at a glance
Here are the limits that come up most often. Each is from the 2010 ADA Standards, Chapter 4, except the conversions to percent, which are simple arithmetic.
| Element | Maximum slope | Percent |
|---|---|---|
| Walking surface, running slope | 1:20 | 5% |
| Walking surface, cross slope | 1:48 | 2.1% (measured) |
| Ramp run, new construction | 1:12 | 8.33% |
| Existing-site ramp, rise up to 6 in | 1:10 | 10% |
| Existing-site ramp, rise up to 3 in | 1:8 | 12.5% |
| Anything steeper than 1:8 | Prohibited | n/a |
Read the table from the top: the flatter the surface, the more freedom you have. Once a path crosses 1:20, you leave the walkway rules behind and enter the ramp rules.
Running slope: the 1:20 line
Running slope is the grade in the direction someone walks or rolls. The ADA standard says a walking surface on an accessible route must have a running slope not steeper than 1:20. That means a path that climbs 12 inches needs at least 20 feet of length to get there.
At that line, the surface changes category. A sidewalk or walkway at 1:20 or flatter is just a walking surface. Steeper than 1:20, it is a ramp, and the ramp requirements apply. One sidewalk guide ranking for this topic puts it plainly: sidewalk slopes need to stay under 1:20, or the surface is considered a ramp.
This matters for a practical reason. A brick front walk that climbs from a Richmond sidewalk to a row house stoop can easily exceed 1:20 because the lot itself is steep. Many older Richmond lots in the Fan, the Museum District and along Monument Avenue sit above the street grade. The walk is steep because the site is.
Cross slope: the 1:48 limit and what 2% means
Cross slope is the tilt across the width of the path. Water needs somewhere to go, so a perfectly level walkway would pond. The standard allows a small tilt but caps it: a cross slope not steeper than 1:48.
You will see this written two ways. The Access Board's public right-of-way rule expresses 1:48 as 2.1%. The reason is practical: digital measuring tools typically read to one decimal place, and the exact figure of 2.08% rounds to 2.1%. So a reading of 2.1% passes and 2.2% does not.
A "2% cross slope," the phrase many readers search, is about 2 inches of fall for every 100 inches of width. It is enough to shed rain and still work for the people the limit protects. The Access Board describes 1:48 as the maneuverable cross slope for most manual wheelchair users and for people with balance impairments.
Why designers aim lower than the limit
Construction is never exact. Brick, bedding and subgrade all vary by a fraction. For that reason, the Access Board's guidance on ramps suggests designing a little under the maximums, with the example of a 7.5% running slope and a 1.5% cross slope so that normal variation still lands inside the legal limit. We follow the same logic on the job: set the walk to the flatter figure and let the tolerance absorb the rest.
How to measure walkway slope
Slope is measured in two directions: parallel to the path of travel (running slope) and perpendicular to it (cross slope). A federal pedestrian facilities handbook ranking for this keyword says the same thing: take readings along and across the route.
A simple method for an existing walkway:
- Use a 2-foot or 4-foot digital level. Longer is better for spotting dips.
- Take cross slope readings every few feet along the path, not just once. A single good reading can hide a low spot.
- Take running slope readings along the centerline, from the sidewalk or driveway to the door.
- Note any spot where bricks have sunk, tilted or lifted. Those are where readings usually fail.
- Record the numbers and photograph the level on the surface.
If the walkway serves a business, a rental or any public-facing entrance, bring those readings to the architect, accessibility specialist or building official who signs off on the project. They decide what applies to your site. We will build to the numbers they give us.
When a walkway becomes a ramp
When the grade is steeper than 1:20, the path must be built as a ramp. Section 405.2 of the 2010 Standards caps ramp runs at a running slope of 1:12 (8.33%). The Access Board recommends using the least possible slope below that maximum, because a gentler ramp works for a wider range of users.
Curb ramps follow the same 8.33% limit. The Department of Justice states that curb ramps built after January 26, 1992 must have a running slope of 8.33% or less. It also notes that sidewalks usually carry a cross slope for drainage, which can change the final rise of a curb ramp, so the planning has to account for it.
Exceptions at existing sites
The standards recognize that some existing buildings have no room to make a 1:12 ramp. In those cases, Table 405.2 lets space-limited ramps run steeper, but only for short rises:
- Steeper than 1:12 but not steeper than 1:10: rise up to 6 inches.
- Steeper than 1:10 but not steeper than 1:8: rise up to 3 inches.
- Steeper than 1:8: prohibited.
These exceptions are for existing conditions where full compliance is not feasible, not a shortcut for new work. If you are building a new brick entry, plan for 1:12 or flatter from the start.
Beyond slope: width, surface and small changes in level
A walkway can pass the slope test and still fail on other points. The ADA National Network summarizes the basics for accessible routes:
- Width: at least 36 inches clear, which may narrow to 32 inches at a doorway or for short distances of 24 inches or less to pass an obstacle.
- Surface: firm, stable and slip resistant.
- Changes in level: no more than 1/4 inch vertical, or 1/2 inch when the change is a 1/4-inch vertical rise plus a 1/4-inch bevel at 1:2.
All three are from the ADA National Network sidewalk fact sheet. We cover width in more detail in our guide to masonry walkway width standards.
The 1/4-inch rule is the one brick walkways fail most. A single paver that has sunk or lifted by a quarter inch, or a mortar joint worn low, can turn a compliant surface into a trip edge. That is why we treat repair and slope as one job.
Public sidewalks versus private walkways
Two sets of guidelines are in play, and it helps to know which one touches your project.
The 2010 ADA Standards and the Access Board's earlier guidelines were written mainly for buildings and facilities on sites. The Public Right-of-Way Accessibility Guidelines (PROWAG) cover pedestrian facilities in the public right-of-way, such as city sidewalks and crossings, and are voluntary until an agency adopts them as enforceable standards.
The final PROWAG rule was published in August 2023 and took effect on September 7, 2023. The Department of Transportation then adopted it for new construction and alterations of transit stops in the public right-of-way, effective January 17, 2025. One provision worth knowing: PROWAG requires a bypass where a blended transition serving more than one pedestrian path has a running slope above 1:48 (2.1%), so people are not forced onto steeper grades than necessary.
For a homeowner, this means the city sidewalk in front of your Richmond house is the city's concern. The private walkway from that sidewalk to your door is yours. A single-family home is not generally the same as a commercial entrance, and who must meet ADA rules depends on the property type. If you are unsure, ask the City of Richmond's building officials or a design professional before you build.
Why brick walkways drift out of slope
Brick is a good walking surface for accessible routes when it is laid well. It is firm, it drains, and it lasts. The trouble comes later, and it is usually one of these:
- Base settlement. A poorly compacted base sinks under foot traffic, creating dips that hold water and break the cross slope.
- Tree roots. Roots lift bricks and turn a 1:48 walk into a hump.
- Water. Runoff from a downspout or a neighbor's grade undermines the bedding and washes out joints.
- Freeze and thaw. Moisture trapped in joints and under bricks moves with temperature swings and loosens the surface.
- Open joints. Once mortar or joint sand wears away, bricks shift and edges rise. Each shift is a potential 1/4-inch lip.
Our brick walkway repair guide walks through how we diagnose these problems. The short version: we measure first, find why the surface moved, and fix the cause, not only the symptom. Relaying bricks on a bad base only buys a couple of years.
Brick and lime mortar: what holds a historic walk and its steps together
Much of our Richmond work is older brick: steps, stoops, garden walls and walkways that were laid long before accessibility standards. Those assets deserve care in how they are repaired, and that is where mortar choice matters.
Traditional masonry used lime mortar. It is softer and more flexible than modern Portland-heavy mixes, so it takes up movement in the wall and lets moisture leave through the joint rather than through the brick face. When a hard modern mortar goes into an old wall, the brick can become the weak part and start to spall. That is why we repoint old brick with lime mortar and match the color, texture and joint profile of the original, so the repair blends in and the wall lasts.
What does this have to do with slope? Two things:
- Steps and landings attached to a walkway. If you are adding a ramp or regrading near an existing brick stoop, the old brick and mortar must be repaired in a compatible way. Our repointing and tuckpointing work keeps those joints sound so the new work and old work move together.
- Historic districts. In Richmond's historic neighborhoods, exterior changes can go through review. Our article on avoiding review delays on historic masonry with sample panels explains how matched brick and mortar samples help. We also do historic brick repair in the Fan and Museum District.
For flat walking surfaces, the right system depends on the job: a mortared brick surface over a sound slab, or brick set on a compacted base. Each has its own risks. If you are thinking about laying brick over an existing slab, read our notes on brick over concrete and bond failure, because the slab's existing slope carries straight through to the finished surface.
Our perspective on slope and brick
We see the same pattern again and again in Richmond. A homeowner calls about a loose brick or a stoop that has pulled away, and when we put a level on the walk, the real problem is that water has been running across it for years. The slope is wrong, the base has moved, and the joints are open. Replacing a few bricks would hide it for a season.
So we start with the level, not the trowel. We check running and cross slope, find where the surface holds water, and decide whether the answer is repointing, relaying a section or rebuilding the base. Where the brick is historic, we match the existing brick and mortar and use lime mortar, because that is how the original was built to last. Where the job is new, we design the slope with margin, so ordinary settlement does not push it out of tolerance.
We will tell you honestly when a project needs an architect or the city's sign-off, and we will build exactly to the numbers they set. Our work carries a 5-year guarantee on materials and workmanship, because we want the walk to still be right long after we leave.
— Thomas
Have a Richmond brick walkway checked
If your brick walk, steps or patio hold water, rock underfoot or have edges that catch a toe, we will look at it. We repair and build brick patios and walkways across Richmond, Virginia, and we do the brick steps and step repair that often connect to them. Estimates are free, no deposit is required, and you pay on completion.
Call 804-324-6304 today and we will schedule a visit. For planning a new path, our guide to Richmond brick walkway costs shows what moves the price.
A planning checklist before you build or repair
Use this list at the start of any walkway project in Richmond:
- Find out which rules apply. A private home, a rental and a business entrance are treated differently. Ask the building official or your design professional.
- Measure what exists. Record running and cross slope at several points.
- Find the cause of any failure. Water, roots and settlement all need different fixes.
- Set targets with margin. Aim under 1:20 and under 1:48 so normal variation still passes.
- Check width and level changes. 36 inches clear, and no more than 1/4 inch between neighboring surfaces.
- Match the old work. On historic brick, match brick and use lime mortar.
- Check the steps. Where a path meets steps, Virginia's residential stair rules apply; see our guide to exterior steps code in Virginia and our notes on brick step design.
- Re-measure after the work. Confirm the finished surface with a level and keep the readings.
FAQ
What is the maximum slope for an ADA-compliant walkway?
The running slope, along the direction of travel, must not be steeper than 1:20, which is 5%. Steeper than that, the surface is a ramp and must meet the ramp limit of 1:12 (8.33%). The cross slope must not be steeper than 1:48.
What is a 2% cross slope?
It is a side-to-side tilt of about 2 inches of fall for every 100 inches of width. The ADA limit is 1:48, which is 2.08% and is written as 2.1% because digital levels round to one decimal place. It lets rain drain off the path while keeping the surface workable for wheelchair users.
What makes a sidewalk ADA compliant?
Beyond slope, an accessible route needs a clear width of at least 36 inches and a firm, stable, slip-resistant surface. Vertical changes in level cannot exceed 1/4 inch, or 1/2 inch with a proper bevel. Lifted bricks and sunken joints are common causes of failure on brick walks.
Do ADA slope rules apply to my home's brick walkway?
It depends on the property. The ADA is aimed at public and commercial facilities, so a private single-family walk is usually treated differently from a business or rental entrance. Ask the City of Richmond's building officials or a design professional what applies, and we will build to their numbers.
Can an existing ramp be steeper than 1:12?
At existing sites with limited space, yes, but only within strict limits. Slopes up to 1:10 may rise 6 inches, and slopes up to 1:8 may rise 3 inches. Anything steeper than 1:8 is prohibited.
Sources
- Chapter 4: Accessible Routes, 2010 ADA Standards
- Chapter 4: Ramps and Curb Ramps, U.S. Access Board
- Notable Changes in Public Right-of-Way Accessibility Guidelines Final Rule, U.S. Access Board
- Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way, Federal Register
- ADA Tool Kit: Curb Ramps and Pedestrian Crossings, U.S. Department of Justice
- Accessibility of Sidewalk Dining, Retail, and Community Spaces, ADA National Network
- Preamble to the Public Right-of-Way Guidelines, U.S. Access Board
- DOT Adopts Access Board's Public Right-of-Way Accessibility Guidelines, U.S. Access Board