Most of Paddington sits inside a heritage conservation area, and the terraces that make the suburb what it is were built in the 1870s–1890s from materials that predate modern cleaning equipment by a century. Lime mortar, soft face brick, sandstone sills, layered paint on render, and cast-iron lacework — none of it was designed to take 3,000 PSI of water.
Why pressure washing damages old terraces
Lime mortar is softer than the brick it holds. A pressure wand aimed at a Victorian wall blows the mortar out of the joints before the brick even looks clean, and once the joints are open, water gets into a wall that has no modern damp course. We’ve inspected terraces where a cheap pressure clean created rising damp problems that cost more to fix than the clean saved. Painted render is just as vulnerable — old paint layers delaminate under pressure and come away in sheets, taking render with them.
How it should be done
Everything on a heritage frontage gets soft-washed: low pressure not much stronger than heavy rain, chemistry matched to the surface, time for it to work, then a gentle rinse. Iron lacework and balustrades are cleaned by hand. Sandstone thresholds and sills get the same treatment we use on sandstone restoration work — never pressure, which erodes the stone face.
Do you need council approval to clean a heritage home? Generally no — cleaning is maintenance, not alteration. But paint stripping, repainting in new colours or repointing can trigger requirements in a conservation area, so if your clean is part of a bigger facade project it’s worth a call to Woollahra or City of Sydney council first.
The payoff
A properly washed terrace doesn’t just look better — removing the biological growth that holds moisture against lime mortar genuinely slows deterioration. It’s some of the most worthwhile maintenance a terrace owner can do.
We work on heritage homes across Paddington, Woollahra, Queens Park and Potts Point. If you own a terrace and want it cleaned by people who understand what it’s made of, request a quote and we’ll assess it in person.
