- To lay the ramp between the support posts, start at the walkway or driveway end. One foot of the starting end of the wheelchair ramp should be embedded into the solid driveway or walkway, as shown in Figure 12.
In cold climates, codes also require that the bottom of the footing be below the frost line. If footings do not extend to this depth, ice can form beneath the footing, pushing the wheelchair ramp up with enough force to weaken the entire structure, a situation called frost heave
.
The uprights should be positioned to allow a minimum of 36 inches between posts measured from the inside of one post to the inside of the adjacent post and be spaced evenly over the ramp's length with the maximum distance between the center of the posts being 8 feet, as shown in Figure 10.
Figure 10 - Wheelchair ramp support post positioning and spacing
The support posts will also act as the main supports for the railing and handrail which runs along the edges of the wheelchair ramp on both sides. The handrail should be 34 to 38 inches high from the top of the ramp surface and should be continuous.
Keep in mind that if you are building a U
shaped ramp that the middle set of support posts provide support for two ramps, as shown in Figure 11.
Figure 11 - U
shaped wheelchair ramp support posts
Figure 12 - Start of wheelchair ramp embedded in concrete walkway
By embedding the ramp in the walkway or driveway you ensure a smooth transition from the ramp to the walkway or driveway and visa versa. The first post which is used to secure the stringer for the ramp and provide the railing support should start at the edge of the walkway or driveway. It should be embedded in gravel and concrete as shown in Figure 8.
A similar installation technique could be used for asphalt, paving stones, as shown in Figure 13, or hard packed gravel.
Figure 13 - Start of wheelchair ramp embedded in paving stones
If embedding the end of the wheelchair ramp is not realistically feasible consider using a threshold ramp to allow convenient and safe access to the start of the wheelchair ramp.
The ramp is constructed using stringers. On a ramp that is 36 inches wide four stringers should be used, as shown in Figure 14, although many individuals will only use three.
Figure 14 - Wheelchair ramp frame
