Cleaning Blocked Gutters
BLOCKED GULLIES AND STACKS (DOWNSPOUTS)
Gullies are notoriously prone to blockages, particularly the older open-grid type where leaves are often the problem. You can prevent this by covering the grid with wire mesh.
Blockages further down are usually caused by a build-up of silt, or by an accumulation of grease and food particles (especially from sinks). In this case, remove the cover or grid and reach into the gully to feel for the blockage; you may have to remove quite a lot of debris before the outlet hole clears.
There are two ways to deal with more serious blockages in the gully trap:
♦ By plunging from the gully end using a cooper’s plunger or drain rod with rubber disc.
♦ By rodding up the pipe connecting the gully with the nearest manhole. (But take care not to force the blockage further into the gully trap.)
Soil pipes and combined soil/ waste stacks rarely block on the vertical section — usually the trouble lies in the bend at the foot of the stack.
In most cases the blockage can be shifted by rodding back up from the nearest manhole, though as with a gully blockage you should take care not to compress it further into the stack. Alternatively, there may be a rodding eye or access trap in the stack itself, allowing you to insert a drain auger.
Failing this, it’s possible to rod down the stack from the top —but only if you have safe access to the roof. It’s best to consider this a last resort.
Waste pipes generally block at the hopper head or at the open end above the gully. Blockages can often be cleared by hand; if not, treat as for other stacks.
Most gully blockages occur in the base of the gully or at the mouth of the trap. They are best shifted by hand, using stiff wire to break up any hard debris.
Stacks often have-on access traps or rodding eyes, allowing you to insert a wire or auger. If not, rod towards the stack from the nearest manhole.