The Modular Stair Company

Installing The Original Modular Stair Form™ is fast and easy! There are numerous ways to install the system based on situational requirements and restrictions but the following instructions are one example of how to assemble a flight of stairs the easiest way.

*Note: All diagrams in this manual have been simplified for clarity and are indicative only.

The Original Modular Stair Form™ has been delivered to site on standard pallets (1160mm x 1160mm x 1160mm) for economical transportation and ease of relocation around the jobsite. The recommended method of moving the pallets to the installation position is by the use of a pallet jack trolley. No crane or hoist is required to place into position. Alternatively, you can carry each step box to is final location with each weighing in at only 8 kg.

Installation is simple with the placement of the formwork decking installed at the required height: Dimension ‘B‘. The system has been designed to fit a 200 mm slab thickness to attain a neat finish to the underside of the stair form.

The width of the landing form deck is the minimum required landing measurement plus 25 mm. (eg Minimum landing 1000 mm + 25 mm = 1025 mm: Dimension ‘C‘). This measurement will set up the bottom step box in the correct position.

The stairwell opening distance, (the horizontal distance between the upper deck and the lower deck: Dimension ‘A‘) is the number of step boxes required x 250 mm (eg 8 steps x 250 mm = 2000 mm).

Set up the temporary support bearers and props that will carry the Original Modular Stair Form™. This support is required prior to pouring the concrete. The below diagrams are an example of the longitudinal bearers required for the system. The actual bearer size and number are to be confirmed by the site structural safety engineer.

Below pictures are a close up of the preferred bearer connection detail top and bottom to the formwork decking. This will ensure that the Original Modular Stair Form™ will sit flush to the underside finished concrete surface.

The second installation option is post slab/landing install. Position the bearers as per the close up pictures again to ensure that the Original Modular Stair Form™ will sit flush to the underside finished concrete surface.

The second method of installation requires the use of the Void Former kit installed into the landing/decking formwork prior to the slab or landing being poured. This will leave the perfect impression on the side of the concrete slab to receive the Original Modular Stair Form™. Again, the correct distance between the upper deck/slab landing and the lower deck/slab landing is measured parallel to the horizon from the data in the above table and diagram.

Once the bearers have been correctly positioned and secure you can start to assemble the step boxes on top of the temporary support structure. Each box attaches to the next positioned together by the internal plastic frame hooks. Ensure that the hooks are fully seated to the adjacent box prior to screwing the boxes together with the screws supplied. The holes are required to line up perfectly to guaranty the perfect fit. The base and the side of each box is required to be flush to the adjacent box. You can either start at the top or the bottom dependant on your situational requirements.

When handling the Original Modular Stair Form™ PPE is required at all times.

Where the top or bottom step box connects with the formwork decking, install the supplied connection bar to fix the first and last step box to the decking with the nails supplied. This connection bar will hold the form in place and ensure a clean finish to the underside of the slab once the formwork has be removed after the concrete is cured.

Install and tie off the reinforcing steel as required by the structural engineers design. The Original Modular Stair Form™ has been designed to have a minimum of 7 – Y12 longitudinal bars inserted down the length of the form and tied into the slab/ landing rebar steel. To help secure the top of each run of stairs to the formwork, the top internal plastic frames can be tied off to the slab/landing rebar to prevent any movement of the form during a pour.

Install the internal handrail system if required for the installation and use it as a temporary handrail barrier so the stairs can be used for site access prior to pouring the concrete.