Sandstone cleaning and sealing in Queens Park

Most Queens Park stone we are asked about falls into three groups. There are cottage facades and chimneys of locally quarried sandstone, some from the 1850s. There are boundary and retaining walls along the streets that slope toward the park, often patched in cement and sometimes painted. And there are front steps and paths, stained by leaves and worn by generations of feet. Each needs a different level of care. We record the condition of every element with photographs before starting, partly for your records and partly because it is useful if Waverley Council or a heritage adviser asks what was done.

The cleaning itself is deliberately mild. Lichen and black growth get a biocide and given days, not minutes, to die back before a gentle warm rinse. Tannin and leaf stains are lifted with a mild cleaner or poultice. Loose salts are brushed away dry. Paint or old coatings are trialled with the mildest stripper that might work, on a small patch, before any wider removal. Hard cement pointing can be raked out and replaced with lime mortar, which acts as the sacrificial part of the wall and spares the blocks either side. No high-pressure tip comes near the stone, and every litre of wash water is recovered.

Old facades and walls in Queens Park are usually healthier unsealed, free to dry after rain and release salts at the surface. Steps and paths are different: a breathable penetrating sealer helps them resist tannin and spills, so sweeping and an occasional wash keep them presentable. Whatever we recommend, we explain it and record the product, date and area. In the conservation areas, ask Waverley Council about any new sealer before it goes on, especially if it would change the stone's appearance. A colour-enhancing product, for example, is more noticeable than a natural-finish one and may draw comment from a heritage officer.