Free draining.

On Monday the tailing were put in behind the retaining wall and down the sides. You can see the white sign-board sheets put up over the 'Ardex Shelterseal' for protection from perforation by the tailings.

The shelterseal sheets (lapped 50mm down to the slab bottom) are over top of a waterproof layer of tar-based paint called moleseal painted down to, and across the following channel). The grooved channel is cut from a step-out of concrete (down the bottom 150mm below the slab) forming the foundation and a 100mm perforated drainage pipe (wrapped in a filter-cloth sock) sits on the channel and takes any excess water round the sides to the front of the section. Overkill? (And that's not the whole story!)

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