On Mon, 07 Jan 2013 17:36:59 +0000, Toby wrote:

On 07/01/2013 17:05, Jethro_uk wrote:
With the respite in the rain the last few days (hasn't rained since
Thursday) all of our patio (18"x18" slabs) is dry.

Except a small patch on one slab. Which rather worringly looks to be
over the line of the drain pipe from the external drain by the side of
the house, to where it joins the inspection pit with the manhole cover
about 2.5m away.

(I know it goes into this pit, as I remove the cover to empty my
caravan loo, so can see the pipe). The pipes a 1960s ceramic type.

Before I start lifting slabs, and excavating, is it possible that a
cracked or damaged pipe could cause an upward dampness like this ? Is
there any easy repair, or (assuming it is damaged) is the proper job to
replace the entire length of pipe ? Would folks say the hardest part of
the job is digging the old pipe free, or actually replacing the pipe ?

As always, TIA guys ...


How deep is the drain pipe?

Well in the inspection chamber the pipes about 18-24" under the surface.
So rising from that to meet the drain.


Really the only way to know for sure is to have a look, and the easiest
way to do that is with a camera, either by getting someone to do a
camera survey, or buying/hiring somthing yourself.

If it is just cracked, or has root ingress on a join, the drain can be
lined with a resin liner, but I think that is out of the DIY scope.

There's no trees near it - although from what I understand roots can
travel quite a bit.

It may be covered under your house insurance.

Hmmm hadn't thought of that.


If the drains are running free, I would be inclided to leave it and see
if it stays like this long term before digging anything up.

As far as I can tell drain is running free. Pouring a bucket of water
down it results in water out the other end !

Maybe, as an experiment, I'll swap slabs ... at least the Mrs will think
I'm doing *something*.