These are used to climb very steep or unstable slopes where steps cannot be built. This might include a steep slope down a river bank leading to a bridge, or a short section on a hillside where it avoids having to build a long hairpin detour.
Railway sleeper
This method of construction is suitable for slopes of about 1 in 2. On slopes steeper than this the notches become awkward to cut, and the alternative method using bearers is easier to build.
- Excavate the line of the ladder to about 250mm deep, and set the two stringers in place, with their outside edges parallel and a half sleeper length apart.
- Using a levelling board and spirit level. Set and mark the position of the first step, and then mark in the notch to the required dimension.
- Measure 200mm vertically up from the notch on either side, check the level, and mark in the position of the second step. Continue to the top, which should total seven steps. Cut the notches.
- Nail the steps in position, using wedges if necessary to get them level and solid. The weight of the structure will hold it in place.
Timber ladder with bearers
This can be built on slopes of up to 1 in 1.2. The angle and length of the slope should be measured accurately using one of the methods described here in order to estimate the materials required.
To prevent the ladder becoming slippery, staple chicken wire around each tread, making sure there are no loose ends underneath which could catch on footwear.
