The Screed-Boss is formed from tough ABS plastic and has been specially designed to give a consistent fall of 1:40 when assembled according to the instructions. The entire matrix is based around the yellow 600mm x 600mm centre section, which gives the starting point for assembly.
Decide where the shower floor is to be installed, marking the appropriate position of the drain, then chase out the sub-floor and install all pipework and the shower trap - ensuring that it finishes in line with the centre of the waste aperture in the matrix. The centre section is then securely fixed into position using rawl plugs and the foot mounting plates.
Fitted to the under-side of the Screed-Boss are many height adjustable feet that enable perfect levelling of the matrix prior to filling with a fairly wet mix of rapid setting cement (4 parts sharp sand - 1 part rapid cement).
How the Screed-Boss works Stage 2
As each additional row of parts is added to the Screed-Boss matrix it must be fully supported and made level using the spacers and height adjustable feet provided.
Check using a spirit level.
How the Screed-Boss works Stage 3
When satisfied that the completed matrix is level on all 4 sides the floor drain and central dish can be connected and the protective trap cover must be fitted to prevent mortar from entering the trap during screeding.
The matrix can then be filled with the screed mix.
How the Screed-Boss works Stage 4
Ensure that the mix is well packed into the Screed-Boss matrix and that there are no voids left underneath.
Then float over the surface so that the ridges of the Screed-Boss are just visible through the screed.
How the Screed-Boss works Stage 5
Allow the screed mix to dry sufficiently before applying any load or removing the shutter boards for the laying of the surrounding floor.
When complete, the entire floor can then be covered directly with slip-resistant vinyl to give a perfectly formed walk-in shower area.