Plumbers & electricians in Abbey Wood

The high ground is Bostall Woods and Lesnes Abbey Woods, ancient woodland along the top of the ridge, and the streets sit below and around it on a slope falling north towards Crossness and the river. Knee Hill is the old dividing line between Bexley and Greenwich, and it still splits the area on paper.

The oldest of the housing is the Bostall Estate, over a thousand cottage style homes put up by the Royal Arsenal Co-operative Society between 1900 and 1914. West Heath adds Victorian terraces and Edwardian semis. The London County Council then built around three thousand dwellings on the Abbey Wood Estate between 1956 and 1959, and since the Elizabeth line arrived there has been a run of new flats near the station.

Above ground those generations have almost nothing in common. A boiler repair in a new flat by the station and a boiler repair in a 1908 Bostall cottage are different jobs, and the electrician Abbey Wood needs for a rewire on the fifties estate is looking at something different again. Below ground it is another matter, because the older drainage was laid in the same material into the same ground.

Tree roots, shrinking clay and the Abbey Wood drain that blocks every year

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Much of the ground here is shrinkable clay, and clay is never still. It shrinks through a dry summer and swells back through the winter, every year, without being asked. The drains under the older houses are salt glazed clayware, short rigid lengths joined with mortar, and rigid is the wrong property to have when the ground around you keeps moving. The joints open, usually not dramatically, just a hairline. But this is a wooded hillside with mature trees in the woods, along the roads and in the back gardens, and in a dry August the wettest thing in that soil is a drain joint that weeps. Roots find it, because finding water is the only thing roots do.

The symptom is rarely sudden. Sinks empty slower than they did, the WC wants a second flush, the bath gurgles when the kitchen drains, then one morning nothing goes anywhere. It tends to happen in late summer, and that is not coincidence: the clay has shrunk furthest, the joints are at their widest and the roots have had a full season behind them. Rodding clears the mass and the drain runs again, which feels like a fix. It is not one. The rods take out what is in the pipe and leave the hole the roots came through untouched, so the run blocks again on much the same schedule, and each time the joint gets worse as escaping water washes fines out from around it.

What settles it is finding the defect before spending money on it. A camera survey tells you whether this is one root at one joint, several joints along a length, or a pipe that has fractured or dropped. Joints can usually be sealed from the inside, with a patch liner over the defect or a full liner along the run, and nothing needs digging up. A pipe broken or displaced far enough will not hold a liner, and that section has to be excavated and replaced in plastic, which does not care what the clay does. Which applies depends on the property: how deep the run sits, whether it passes under an extension or a driveway, and whether the tree behind it is one you want to keep.