Roof Cleaning in Marrickville

What settles on a Marrickville roof is different from anywhere else we work, and it is not organic.

The suburb lies beneath the flight path, and the fine particulate that comes with that, combined with soot from the Illawarra Road and Marrickville Road corridors, builds an even grey-black film across the whole roof plane. Because it lands uniformly there is no obvious dirty patch to prompt a clean, and it is slightly greasy, so rain streaks it rather than clearing it.

The building stock complicates the job. Much of Marrickville is Victorian and Federation terraces and semis, which means shared party walls, box gutters running between neighbouring roofs, and slate or Marseille terracotta laid over a century ago. Workers' cottages behind them often carry original corrugated iron, now well past its first coat. None of that tolerates high pressure: slate delaminates, aged terracotta has lost its glaze, and iron sheds whatever paint is left.

Down toward the Cooks River the ground is damper and the plane and fig canopy heavier, so the southern pitches there add moss to the soot.

Access is the practical constraint. Terrace roofs are reached over a neighbour's property or from a narrow rear lane, and we plan that before the day rather than on it.

On a terrace, roof problems are rarely confined to one house, and that changes the maintenance calculation.

Box gutters running between neighbouring roofs drain to a single outlet, and when that blocks the water does not spill over an edge. It backs up under the tiles and into the roof cavity, frequently on the other side of a party wall. A blockage you did not create can become water in your ceiling, and sorting out who pays is a conversation nobody enjoys.

The soot film has its own cost. Left sitting on aged terracotta and slate it holds moisture against a surface that has already lost its glaze, and on original corrugated iron it accelerates the breakdown of what paint remains. Replacing a slate or iron roof on a heritage terrace is specialist work priced accordingly, and in a conservation area the council will have a view on the replacement.

There is a straightforward presentation return too. Marrickville roofs are highly visible from the street and from the rear lanes, and on a row of terraces the difference between a cleaned roof and its neighbours is obvious.

Because access is planned rather than improvised, we also get a proper look at the box gutters and valley irons while we are there.