Mortar only under padstone.
Slate or steel shims between pad and lintel.
It sounds like the wrong sized steel/lintel has been fitted.
You need an S/E to calculate the new lintel ( structural works ) which will carry...
You will need to ply over for a decent finish, the boards will show through the rubber.
Put a perforated felt layer on first ( lightly tacked )...
If the footings/brickwork have all been done, it should have a PRC certificate, if it has then go for it.
All structural works need to be done to regs, in your case a Structural Engineer should sort this for you.
Alex, if its an 06 or earlier model get shot of it, nothing but trouble with gear boxes, clutches , steering racks and pumps.
Then get a decent...
If the damage is deep, pva then bond it out level.
You haven't said if its new or old board, or previously skimmed.
Whichever, Febond Blue-Grit...
Straight cut in render.
Stepped in brick.
Tile backer board ?
You cant sand/cement render over p/b
It will be okay, flaunch up the back of paviors.
Celcons, and no good for out side, even if rendered.
The ridge can be re-used with dry system, battens need extended on the ridge via metal clips for ridge clips to be screwed down.
If its for...
If the walls are sound, either 2 coats of pva or 1 blue grit, then 2 coat skim.
Why would any one buy this.
Dust bin lids have been around for many years.
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