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Re-lining the main drain

As you’ve probably gathered, this house is anything but a “new-build”. It’s got way more character than a identikit modern box on an estate, but the down-side is that much of it is many, many decades old and therefore needs attention. The main foul drain leading to the septic tank is a case in point. It’s made of pottery segments, and was showing signs of damage from plant roots. Twice in the past few years, the drain has got blocked, and the last time that happened a CCTV inspection showed several cracks and displaced joints with roots creeping through. It wasn’t in imminent danger of collapse, but that was the inevitable outcome if I just let nature take its course. And you can bet, knowing my luck, that it would collapse catastrophically at the worst possible time – probably on a bank holiday with a foot of snow on the ground! And if it had got that far, the only option would have been to dig up the drive, completely replace the collapsed pipework, and relay the drive on top – we’re talking many, many thousands of pounds.

Much the more cost-effective option, it seemed to me, was to do some pre-emptive maintenance before things got really bad. Hopefully, it should also stop the issue I’ve been having with repeat blockages – which are really not very pleasant to deal with! The idea was to re-line the damaged segment of my main drain with what is effectively a resin-impregnated balloon. The new liner is put in place between two inspection hatches, then inflated with compressed air while it cures. It’s a non-invasive technique, so doesn’t need my drive to be dug up, and takes two men less than a day.

I therefore arranged to take today off and get the job over with before Spring really gets underway and the plant roots put on a growth spurt. Two vans full of equipment and chemicals turned up at 9am, and they were all packed away and gone by 2:30pm. The house has a faint whiff of solvent, which seems to be percolating up through the basins in the bathrooms – unsurprising I suppose, given that the liner won’t be fully cured for another 24 hours. In the mean time though I can use water as normal, including running the washing machine or having a hot shower. I’m just not allowed to used any harsh solvents (e.g. sink unblockers) until it’s fully cured. But after that, the new liner should last at least ten years, probably longer.

The job was done with a minimum of fuss, and according to the men went very smoothly and was a “textbook job”. I had a look at the CCTV imagery before they left, using a sort of endoscope along the new section of the drain, and it is all smooth and looking much better than before. The only minor issue from my point of view was that, while the new liner was curing, my main drain was effectively blocked by an inflated “balloon” which formed a watertight seal at the inspection hatches. That meant I couldn’t flush the toilets or use any significant amount of water for the three hours or more that the balloon was in place. That was somewhat tedious, but entirely manageable.

As I waved the men off this afternoon, I said to them “Please don’t take this the wrong way, but I sincerely hope I never see either of you again!” They laughed and said that there was absolutely no reason why I should need to call them out again – at least for that 10m section of the drain.

That’s another job ticked off the to-do list. Roofers last week, drains this week. These things always seem to come in threes, so I’m expecting to have to deal with more workmen again in the near future…….