Replacing broken drains on a recent job in Northcote:
We recently completed a job in northcote, Auckland. Their drains kept blocking. Heres why:
About eathenware drains
Auckland properties have a lot of earthenware (glazed clay pipe).
Earthenware pipe was layed in short sections and unlike todays PVC glue joins the joins in earthenware drains are far easier to break or pull apart due to their brittle nature.
One of the tell tail signs of a broken drain is the drain re blocking over and over, even after being cleared by a hydro jet or drain unblocking unit. If your drains are continually blocking or overflowing, we suggest getting CCTV footage of the drain.
CCTV Drainage Camera
This camera on a cable allows the operator to push it down the drain while getting a live feed on their screen above ground. This will tell the drainage team where the issue is and how much of the drain will need to be replaced to ensure the drains run as they should.
Drainage cameras can tell the plumber/drainlayer, the depth of the drain, the fall of the drain, where the drain goes and its connections underground. It can also record which parts that appear to have imperfections.
What causes a drain to block
Typically, issues are caused by large trees. The tree roots can move or break the drains or even grow inside the drain itself. It is also very common for drains to sink ‘drop’ in sections where the backfill of the original trench was not of a sufficient quality or suited to the existing ground.
Issues can also arise after renovations where land is moved, and new load is on areas of ground that the drains run through.
How we fixed a blocked drain in Northcote
An example from a recent job completed in Northcote, Auckland: The drains had been unblocked by the hydrojet 2 weeks earlier but were blocked again causing a leak in the downstairs toilet. We had CCTV footage taken of the drain showing that the first 2 meters had sunk and meant the water was pooling and having to run up hill. The sunken section had pulled the join apart and caused a step in the drain too which toilet paper was able to build up on and eventually block the drain completely.
We excavated the area and removed the earthernware pipe back to where the drain was salvageable and in good condition. From here we installed new 100mm PVC drains to the existing connections. This was then backfilled with SAP7 fine drainage metal and compacted to support the drains.
