Laying floor on insulation board

[jmargush]

When laying the brick on the insulation board do I lay it directly on it? or do I mix sand fire clay and water and spread that on with a notched trowel?

[Greenman]

A fine layer of dry sand is all that you should need, if you need anything at all. If your bricks are consistent it should not be an issue. Once you start to lay them you will be able to see if you need the sand.

[sharptailhunter]

I just barely laid my floor ricks down yesterday. I did a 50/50 mix of fire clay and sand. It was pretty easy to do. Like Greenman said, that's of your floor really even needs it. Mine was pretty uniform without the sand mix.