Sandstone cleaning and sealing in Malabar

Sandstone around Malabar homes often sits on a slope above the bay: retaining walls holding terraced gardens, stairs linking the levels, and paving at the top where the view is. Facing the water, the stone carries a salt crust and sheds grains along its edges. Lower levels stay damp and grow algae, and run-off after rain leaves muddy tide-marks along walls. Near the headland and the golf course, leaves and seed pods stain paths. Front fences on the flatter streets add traffic grime. We work through the property level by level on the inspection and trial products on an inconspicuous patch of every surface before recommending a method.

Loose salt is swept and vacuumed away while the stone is still dry, and only then is fresh water introduced, gently; salt lodged deep inside a wall is coaxed out with a clay poultice left in place. Green and grey growth is sprayed and left to wither before anything is rinsed. Leaf tannin responds to a mild cleaner made for sandstone, with a poultice for stubborn shadows. On this stone, rinsing is always done with a wide, gentle spray or warm water, never a cutting jet. We clean from the top level down, catching water at each bund and vacuuming it up, so nothing runs toward Long Bay.

Sealing matters most on the exposed surfaces in Malabar: terrace paving, stair treads and wall caps that take salt spray. A vapour-open impregnator lets far less salty water into the pores but still allows the block to dry, and that balance is what keeps coastal sandstone sound. Walls retaining soil stay unsealed. We lay out natural and enhancing samples, apply sealer only in calm, dry weather, and record what was used and where. On terraces facing straight into the bay, protection wears faster than elsewhere, so we suggest a yearly check by splashing a little water and watching whether it beads or darkens the stone.