Contractors installing insofast against the extremely uneven stone wall pictured below used spray foam to attach the panels.
How To Level An Uneven Wall. Check out our how to tile. If you're tiling directly onto the wall, however, leveling clips and wedges will force the edges of the tiles together and create a smooth, even wall tile installation, no matter how uneven.
How to Stencil a Wall + A Trick to Fix the Uneven Edges ... from whatsurhomestory.com
The problem is that the wall is uneven. The system is a great improvement over the old plaster and lath process, but there is one big drawback: To check the floors suitability, lay a 2 metre straight edge and rotate it gradually through 360 degrees.
You can see the uneven line in the pics before and after.
The cheapest solution would always be don't. How large are the tiles your considering, and if you know it what is the weight of them per m2? Im more than ok with having drop offs as i eventually will. * remove old floor, build new concrete floor.
