Calculate ramp gradient: How steep can my ramp be?

• 1. How is the gradient of a ramp calculated?
  • 1.1 Example calculation
  • 1.2 Important note on ramp length
• 2. Maximum gradients for wheelchairs and rollators
• 3. Maximum inclines for pallet trucks and forklifts
• 4. Maximum inclines for cars

The permissible gradient of a ramp depends on the intended use and is usually between 5 % and 15 %.
An example: While a 5 meter long ramp may be sufficient for a car, an electric pallet truck requires a ramp of 15 meters in length for the same height difference.
In the following, we look at which ramp gradients are recommended or prescribed for different applications.

Gradient (%) = (0.30 m / 5.00 m) × 100 = 6 %

This can be used to check whether the planned ramp complies with the prescribed gradient specifications.

So if the inclined length and not just the horizontal length is relevant, this calculation should also be carried out.

If you want to create barrier-free access, you need to distinguish between two areas:

• Public space
• Private area

Public space

In public spaces, the maximum permissible ramp gradient is 6%.  
In addition, an intermediate landing must be provided after 6 meters at the latest to allow wheelchair users to take a short break.

In Germany, steps usually have a step height of approx. 0.185 m. With a gradient of 6%, the required horizontal ramp length per step is approx. 3.08 m. If there are more than two steps, an intermediate landing is usually required.

Private area

On private property, there are no such strict regulations regarding the maximum ramp gradient. Nevertheless, it has been shown that the recommended gradients from the public area are sensible and should not be exceeded if possible.

The recommended ramp gradients for a step height of approx. 0.185 m:

These values illustrate how much space a ramp suitable for everyday use requires. Therefore, a simple staircase with three steps is often not replaced by a 9 meter long ramp, but by a scissor lift table or another space-saving solution.

Important note in advance: The values given here for the maximum incline for hand pallet trucks, electric pallet trucks and forklifts with driver's seat are based on our many years of experience in the manufacture of goods lifts.
Binding information on the maximum permitted incline can be found in the operating instructions for your industrial truck, as it is not possible to make a generally valid statement due to the large number of models!

At first glance, it may seem surprising that the maximum incline for hand pallet trucks is higher than for powered electric pallet trucks. 
However, this is due to the design: The limiting factor is not the drive power, but the ground clearance. Electric pallet trucks often have very low ground clearance and can therefore touch down.

Minimum ramp lengths for typical applications

As pallet trucks and forklifts are rarely used to climb individual steps, we have selected practical examples for calculating ramp lengths that are more suitable for everyday use:

Our products are not only used for wheelchairs and hand pallet trucks, but also for cars - for example for:

• transportation to the basement,
• as a car lift for car dealerships,
• or as a garage that can be lowered into the ground.

To calculate the required ramp lengths, we use the Lower Saxony Garage Ordinance as a guide. This specifies (simplified) the following maximum gradients for cars:

Example calculation: Ramp length for a garage in the basement

Assumptions:

• Average room height: approx. 2.40 m
• Base thickness: approx. 0.25 m

Based on these values, the following minimum ramp lengths result:

The calculation shows that the ramp length depends heavily on the permissible gradient. While a private garage entrance can use a steeper ramp, flatter gradients are required in public areas, which significantly increases the required length.