1. The GreenLock S22 step and seating blocks are ideal for installing Steps or Seating arrangements with ease and to any length. They are non-slip, efficient to install, economical, and durable. The S22 can be laid with a 110mm riser with a 350mm tread, 147mm riser with a 330mm tread, or a 220mm riser with a 270mm tread. The 147mm riser is the most common step height used.

2. Stairs higher than 2m should be designed by an Engineer.

3. Check the in-situ soil condition to determine the correct type of sub-base to be used.

4. Excavate to line and to the required gradient or bench to accommodate theS22 step block.

5. Compact the benched soil, and if necessary, use stone or soilcrete (3% cement mixed with sand) for additional support and stability.

6. For a staircase above 2m in height, a foundation should be cast as per the engineer’s instructions, using 20MPa concrete at the toe, to accommodate the first row of steps and to support the rest of the staircase structure.

7. Set out the first row of concrete-filled blocks and place on a thin mortar bed.

8. Fill the block cavities of the S22 block with a wet concrete mix and insert a Y8-Y12 reinforcing bar through the wet concrete and all the blocks. This will assure a solid footing for the first step row.

9. Repeat the same at the top of the stairs with the last row of steps installed.

10. Compact the imported subbase or the soil behind each step as you progress with each row of steps installed.

11. Ensure that the steps are installed horizontally in all directions. A very slight angle (max.2 degrees) toward the rounded front edge of the block tread can also allow storm water to cascade over the step edge to eliminate water pooling on the steps.

12. It is strongly advised that the two horizontal cavities of the S22 blocks should be closed with a mortar mix at each end, to prevent rats, snakes, and insects from sheltering or nesting in them.

13. The project engineer may require all the rear cavities of the blocks to be filled with a semi-wet cement mix, and that a Y8–Y12 reinforcing rod is inserted through the width of the step tread. This increases the strength of each step and the strength of the whole staircase structure.

14. In any event the first and the top step should always have reinforcing bars pushed through the stillwet cement mix. The easiest way to do this is to fill each S22 block to be installed with the semiwet cement mix before laying the block into position. Once one full step width is installed, push the cut-to-length reinforcing rod through all the blocks. Touch up both cavities of the two end blocks with the appropriate colour mortar mix to a smooth plastered finish.

15. Use an experienced contractor to install your steps and seating, to eliminate possible failure. Ask your supplier to recommend a suitable contractor.

16. A hidden 12V or 24V outdoor strip light may be installed in a groove at the back of the 147mm riser, by a suitably qualified electrician. The strip light can only be installed in the 147 mm and the 220mm riser, giving a classy indirect lighting effect.