32" build in Calgary, AB - pompeii neapolitan

[IH123]

I had a 10ftx10ft gazebo put over the site, also cut the ceramic fibre board and CaSi boards and put them in final location. the ceramic fibre board had aluminum foil wrap put on top of it and HVAC aluminum tape on the sides, sides are picked by a needle to let any steam escape from sides (top stays sealed to prevent ceramic fibre going into hearth and cooking chamber ). I noticed the CaSi board cuts are not so difficult to dislodge from their position so I am wondering if a 1/8"-1/4" layer of refractory mortar over the CaSi top (sides kept bare) layed and let cure before any bricks put on it, will keep the boards together while constructing the bricks:

[david s]

As posted previously a wet mortar applied over a very hygroscopic material, particularly if the layer is thin, is nigh on impossible because the moisture will be immediately sucked out of the mortar. Apart from the difficulty in obtaining a flat surface the moisture required for the hydration process will be reduced perhaps to a level which will impair strength. Most builders use a dry mix of fine sand and powdered clay. This acts as a levelling medium because there will be small variations in the thickness of the floor bricks. The dry mix also allows for free movement of individual floor bricks as they receive differing rates of thermal expansion depending on their location.

Try your proposed method by all means, but I think you will have trouble.