Sandstone cleaning and sealing in Curl Curl
Curl Curl homes are built into sandstone hills, so the stone is part of the garden, not just the paving. Cleaning it properly means treating rock, walls and steps differently.
- Curl Curl 2096
- $20 million public liability
- Price on request
A typical Curl Curl hillside block can include natural sandstone rock, a few levels of retaining wall, steps connecting the yard to the house, and sandstone paving around an outdoor area. The natural rock carries lichen and black staining built up over years. Retaining walls, damp from the soil behind them, grow algae on their shaded faces and may show white salt bloom where moisture evaporates. Steps and paths gather leaf staining and traffic grime. On the side facing the ocean, salt deposits add to the mix. We start every quote by walking the property and noting which surfaces have which problem.
Our cleaning method follows the stone. Natural rock and walls get a biocide pre-treatment that kills lichen and algae at the root, followed by gentle brushing and a low-pressure rinse. Steps are cleaned from the top down with water recovered at each landing. Salt bloom is removed with fresh water and brushing, with a poultice reserved for stubborn patches. We never use hydrochloric acid or a narrow high-pressure jet: acid stains Hawkesbury sandstone orange, and high pressure cuts into the surface and leaves it rougher, so dirt returns faster.
Sealing in Curl Curl is selective. Paving, steps and entertaining areas usually do well with an impregnator, which holds stains and salt at the surface for longer while keeping the stone matte and safe underfoot. Natural outcrops and retaining walls usually should not be sealed, because they need to release moisture through the surface. Before sealing, the stone has to be completely dry, and with lagoon-side humidity that can take several days. We check moisture before applying anything and record the product, so future maintenance is simple. Ocean-facing paving needs a yearly water-drop test.
Frequently asked questions
Sandstone questions we hear in Curl Curl.
Will cleaning remove lichen marks from our sandstone outcrop?
The lichen will die back after treatment. Pale marks where it grew can remain for a while and usually fade as the stone weathers over the following months.
Should our retaining walls be sealed?
Usually not. A retaining wall has wet soil behind it and needs to dry out through its face. Sealing can trap salt and cause the surface to break down faster.
Our sandstone paving is orange in patches. What caused it?
Orange patches are often iron staining, sometimes from a past acid wash or from metal fixings. A poultice can draw much of it out. A trial patch shows how far it will fade before we treat the whole area.
How long does sealed paving stay protected?
It depends on the product, sun and traffic. Sheltered paving can last years. Ocean-facing areas need checking yearly with a water-drop test.