Sandstone cleaning and sealing in Palm Beach

Palm Beach sandstone spans a century. At one end are the walls of the early cottages and bungalows, built from local stone around the time of the First World War; at the other are the retaining walls, stairs and terraces of larger, more recent estates. The older stone has spent its whole life in salt air, so the exposed faces are often soft, flaking or powdery, with a white bloom after dry spells. Many old walls also carry hard cement repairs, which push moisture and salt into the stone beside them. Estates on the bush fringe add lichen and leaf stains, while newer paving is denser but still drinks up salt if left unsealed.

With old stone, the assessment matters as much as the clean. Our technicians check for earlier coatings, cement patches and areas that are already fragile before deciding how to proceed. Work begins with fresh water and soft bristles, and growth is treated with a biocide that is given time to dwell. Pressure stays at the low end, and the weakest areas are done by hand. Acids are never used, because they draw iron out of Hawkesbury sandstone and leave orange stains. Persistent salt bloom may need a poultice. Wash water is captured rather than sent toward Pittwater or the ocean, and if a stonemason is needed, we will say so.

For the early sandstone houses, our usual advice is not to seal the walls. Old masonry needs to let moisture out through its face, and a sealer can hold salt inside where it does the most harm. Horizontal surfaces are another matter: paving, steps, terraces and pool coping all benefit from a breathable impregnator that slows salt and staining while keeping a matte, natural finish. We wash off surface salt, let the stone dry completely and pick a still day. Where a home is heritage-listed, we discuss it with you before sealing anything. Ocean-side paving should be water-drop tested yearly; the Pittwater side usually lasts longer.