Tarragindi is terracotta country. Steep treed streets below Toohey Forest, a lot of houses approaching or past a hundred years old, and roof after roof of old terracotta tile — which is the one roof material you should never let anyone pressure clean.
An old terracotta tile has a fired surface that has already lost most of its glaze to sixty or eighty years of Brisbane sun. Underneath that is porous clay. Put a pressure washer on it and three things happen: the remaining surface is stripped, the tile becomes more absorbent than it was, and the mortar pointing along the ridges and hips — which is what is actually holding the capping on — gets chewed out.
That last one is the expensive part. A roof that looked clean on the day can start letting water past the ridge capping the following wet season, and re-pointing a roof costs many times what the clean did. We have seen it, and we will not do it.
What we do instead is a treatment programme: chemical applied at low pressure, then reapplied on roughly a three-month cycle. The moss and lichen die and weather off gradually rather than being ripped off. It is slower and it takes patience, and it is the only method we are willing to put on a hundred-year-old roof.
This is not a one-visit fix. If you want your terracotta roof looking dramatically better by next weekend, we are not the right call — and the people who say they can do that are the reason a lot of these roofs need re-pointing.
No pressure was used on this roof at any point.
Tarragindi shares its housing history with Moorooka and Annerley — a great many of these homes are a century old, which means painted timber, original casement windows and paint that quite possibly predates 1970. All of that gets a soft wash rather than pressure, with the rinse contained rather than run into the garden.
The streets climbing toward Toohey Forest carry the same leaf load and shade problems as Mount Gravatt: gutters that fill with gum leaves year-round, and driveways on a slope that turn slick with algae after rain. The gutters are worth doing before storm season; the driveway is worth doing for traction, not just looks.
Also working nearby: Annerley, Moorooka, Camp Hill and Mount Gravatt.
