The sleepers are set in a concrete footing. If they are to be used as a retaining wall and backfilled you can also run a rail or steel support beam along the back and screw or bolt the sleepers to that to reduce any later movement/warping etc
The timber is Cupressus macrocarpa - left to weather it goes a very nice silvery grey but must be in a sunny, dry place for this - if too damp it will rot and will collect black mildew etc.
Earthwork Landscape Architects
Brian Wark
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