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Ramp guide

Threshold ramps: what they are and when they are enough

A threshold ramp is a small, removable ramp that sits at a doorway lip, a garage step or a low entrance edge and smooths the transition. For a couple of inches of rise it is often the entire solution. Here is how they are sized, what rules actually apply, and when the rise means a real ramp instead.

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A threshold ramp is a small, removable ramp that sits at a doorway lip, a garage step or a low entrance edge and smooths the transition. It is the least construction you can do and still fix a real access problem, and for a couple of inches of rise it is often the entire solution. The honest question is when it stops being enough.

What counts as a threshold ramp

Threshold ramps are placed, not built. You set one over a raised door saddle, a sliding glass door track, the step from a garage into a house, or a low porch edge, and you can lift it away again. Most are one-piece plates, wedges or short adjustable ramps with a non-slip surface, rated for outdoor use where the door is exposed.

The category blurs gently into portable ramps. As a rule of thumb, a threshold ramp handles a lip or a low rise at one specific spot; a portable ramp is a foldable ramp for a step you might meet in more than one place. The ramp type comparison covers the whole family.

Typical sizes and what they cover

Manufacturer ranges are the best guide to what threshold products actually do. EZ-ACCESS, one of the larger makers, describes three common classes:

  • Angled entry plates for thresholds up to 2 inches, in three lengths (8, 10 and 12 inches) matched to the height. Light, cheap, and ready in seconds.
  • Adjustable angled entry ramps with screw feet that set the exact height, in 12, 24 and 36 inch lengths, covering door thresholds up to about 5.875 inches.
  • Modular entry ramps in fixed heights from about 1 inch to 6 inches, 34 inches wide, assembled by sliding sections together.

Sizes as published on the EZ-ACCESS site and checked October 17, 2026. Other makers cover similar ranges; the pattern is fixed heights from under an inch to around 6 inches.

On cost, the published bands are modest: rubber threshold and entry ramps run about $55 to $165 (HomeAdvisor, as published in our cost guide), and portable and threshold ramps generally land between $50 and $400 with no installation at all (101 Mobility, as published in the comparison).

The rules that apply, and the ones that do not

Here is the verified picture, without inventing anything that varies by state or city:

  • Permits: because a threshold ramp is placed, not built, it usually falls outside the building permit process. Modular or anchored work is a different conversation. The permit guide has the details.
  • ADA: the ADA's ramp rules apply to ramps on accessible routes at government facilities and businesses open to the public. If your threshold ramp is part of a workplace or a public entrance route, the 1:12 slope ceiling and the rest of §405 apply to the route, and a steep entry plate may not satisfy them. Private single-family homes are generally not covered by ADA Title III.
  • Residential code: for built ramps, the IRC baseline matters. A ramp serving the required egress door is capped at 1:12 where the site allows; other residential ramps are capped at 1:8 (R311.8.1, summarized in the requirements guide). A threshold ramp is steeper than both by nature: it has to fit inside a doorway. That is acceptable for a lip of an inch or two, and a judgment call at a full step.

That last point is the practical heart of it. A 2-inch threshold sized for a 12-inch plate is working at roughly 1:6, far steeper than any ramp code allows. It works because it is short and it is flat ground at both ends. When the rise grows, steepness stops being a convenience and starts being an obstacle.

When a threshold ramp is enough, and when it is not

A threshold ramp is usually the right tool when:

  • The rise is a lip or a low step, roughly up to a couple of inches.
  • The need is temporary, or you rent and cannot build.
  • It is one specific spot: a side door, a garage lip, a sliding door track.
  • It backs up a main ramp or covers the door you actually use day to day.

Start thinking about a real ramp instead when:

  • The rise is a full step, roughly 6 inches or more.
  • The entrance needs a compliant accessible route for visitors, customers or staff.
  • A wheelchair or scooter has to climb it daily, not occasionally.
  • The door swing, the landing space or the street slope leaves no safe place to put it.

For those cases, the question becomes what 1:12 actually needs. A 6-inch rise needs at least 6 feet of ramp, a full step of about 7 inches needs 7 feet, and the math runs from there (see how long a ramp should be). If that length makes sense for your entrance, the ramp calculator turns the rise into a plan, and a modular ramp is often the fastest way to get there.

Fitting one properly

  1. Measure the true rise at the door, top surface to bottom surface, the same way you would for any ramp (the requirements guide shows the method).
  2. Check the door. A ramp that lifts the walking surface can foul the door swing or the screen door; adjustable-height models exist precisely because small variations matter.
  3. Pick the surface for the weather. Textured or slotted surfaces keep grip in rain; smooth plastic does not.
  4. Decide on securing. Some plates are meant to sit loose, others have pre-drilled holes for fixed placement. A loose ramp on a public route is a hazard; secure it or store it.

A threshold ramp is one of the cheapest, quickest accessibility wins there is. It is just worth being clear about its job: it smooths a small height change, and it is not a shortcut past the slope math when the rise is real.

Sources

All links checked October 17, 2026. This is general information, not product or legal advice. Product ranges and local rules change, so check current specifications and confirm your project with your local building department.