Need advise please, before a builder pulls the wool over my eyes.
I have a double garage ( with a centre wall separating them ) and am seriously considering building upwards ( sideways is not an option because of land slope and layout, and the sea view from the top floor would be stunning ). I want to add a double room flat above the garage, with a concrete slab between, and a tiled roof.
I was told that the existing single thickness wall must be increased to a double thickness wall, which I understand would be needed to take the weight of the slab and top floor walling ( in addition to the existing tiled roof's weight ).
So what's the procedure ?
Would the existing concrete floor need to be lifted to increase the foundation width ?
How is the new (inside) wall attached to the existing wall ? I assume the two need to be fixed together somehow.
Would the walls on the top floor all be single thickness ? My thinking is that if the existing single layer brick walls can support the existing tiled roof, the same should apply on the top floor, as long as the ground floor walls can support the slab and top floor walls.
Not too sure what technical terms to google, so any experienced advise would be appreciated.