Limestone built Fremantle, Cottesloe and Claremont. It handles moisture well until somebody seals it.
Talk it throughRising Damp Perth assesses and treats damp across the Perth metropolitan area.
A limestone wall takes up moisture and releases it again through its face. That cycle is normal and the wall is built for it. The stone is soft, porous and forgiving — as long as the moisture has somewhere to go.
Cement render and modern acrylic paints are far less permeable than the stone behind them. Moisture that used to leave through the face now travels higher up the wall looking for an exit, and the salts it carries crystallise behind the coating. Those crystals expand, and the render comes off in sheets. The coating did not fail — it worked exactly as designed, in the wrong place.
From Cottesloe to Scarborough, salt also arrives on the wind and settles on the wall. Salt is hygroscopic: it pulls moisture out of humid air, so a coastal limestone wall can read damp even in a dry spell. Treating the moisture without removing the salt leaves half the problem in place.
Lime-based renders and mineral paints let the wall keep breathing. They are less familiar to a general painter and cost more, and they are the difference between a repair that lasts and one that has to be done again in three years.
We carry out assessments across the Perth metropolitan area, including:
Rising Damp Perth