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Guide · Effectiveness

Do speed bumps actually work?

Short answer

Yes at the device, and that is the point: a driver physically has to slow to 5–10 mph to cross. FHWA and ITE traffic-calming reviews report meaningful reductions in 85th-percentile speeds at humps and bumps. The effect fades between devices, so the result depends on spacing — 150–250 ft on lot aisles, 250–500 ft on private roads — far more than on the individual unit.

Why devices beat signs on private property

A posted limit in a private lot is advisory and relies on the driver choosing to comply. A raised device removes the choice. That difference is the whole reason traffic-calming programs exist.

Control	Depends on driver choice	Typical effect at the point
Posted limit sign	Yes	Small, fades quickly
Painted markings	Yes	Small
Speed bump (2–3 in)	No	Forces 5–10 mph
Speed hump (3–4 in)	No	Forces 15–20 mph

Spacing is the variable that decides the outcome

One bump in a 600 ft aisle produces one slow point. Three bumps in the same aisle produce a slow aisle. Count the length, divide by 200 ft, and add one at the entrance — that is the calculation that turns a device into a result.

Setting	Spacing	Target speed
Parking lot drive aisle	150–250 ft	5–10 mph
Private road / HOA street	250–500 ft	10–15 mph
Warehouse yard, dock approach	At each conflict point	5 mph

Where they are the wrong tool

On a designated fire-response route where the department objects, on a marked accessible route, on a steep grade, or immediately after a blind turn. In those cases relocate the device rather than lower it — a device nobody sees in time creates the vehicle complaints people blame on bumps in general.

Buying terms

In stock in the USA — LTL freight to all 48 contiguous states.
Purchase orders accepted from companies, 3PLs, HOAs, school districts and cities.
Pallet and container pricing past about 10 lanes.
Anchor hardware and end caps included; 5-year commercial warranty.
Quote with landed freight answered within 24 business hours.

Frequently asked

Do speed bumps actually reduce speed?

At the device, yes — that is the part that is not in dispute: a vehicle physically has to slow to cross. FHWA and ITE traffic-calming literature reports meaningful reductions in 85th-percentile speeds at humps and bumps. The reduction fades between devices, which is why spacing matters more than the individual unit.

Do speed bumps reduce accidents?

The mechanism is speed: lower impact speed means fewer and less severe pedestrian and backing collisions, which is why traffic-calming programs use them in parking lots, school zones and residential areas. Outcomes on any single property depend on layout, volume and how many devices are installed.

How far apart do they need to be to keep working?

150–250 ft on parking-lot drive aisles and roughly 250–500 ft on private roads. Beyond that, drivers accelerate back to their original speed between devices and the average speed barely changes.

Are signs alone enough?

Rarely. On private property a posted limit is advisory and depends on voluntary compliance. A physical device does not. Signage supports the bump; it does not replace it.

What about drivers who swerve around them?

That is a coverage problem, not a device problem. Size the unit to the full lane width using end caps so there is no gap at the curb, and place it where the geometry does not allow a shortcut.

What does it cost to find out?

One lane: $260–$520 in materials for the 3 in modular profile or $360–$660 for the 2.4 in heavy-duty, plus freight. Because it bolts down and unbolts, a single-lane trial is a real option before committing to the whole property.

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Both profiles, dimensions, load rating, price per 12 ft lane and what we need to quote freight. One field — no phone call required.

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