Does anyone know what this damp area might be below strange downpipe/drain situation

verytired11

I am really panicking and wonder if anyone can help shed light on this.  The buyer's surveyor has picked up that there is a problem at the back of my house.  You can see on the attached picture that the downpipe from the guttering appears to go back in the house - which it does, and then straight into the ground into a drain.  As can be seen from the photo there is clearly a problem somewhere as the brickwork is looking very damp, and the paving slabs in the area are cracked.  I have now noticed some cracking above the back door (on the plaster inside) and a small gap opening up between the door surround and the wall.  I am terrified that this may be subsidence caused by some kind of leaking of the drain.  If this is the case, will it be easy to fix - in other words, if the drain gets fixed will that resolve the cracking problem, or might further underpinning work be involved.  The back of the house is actually already underpinned.  It's just that I have started to notice cracking in the plaster everywhere in the house.  At the moment all the cracking is hairline, but some of it is definitely recent.  Any thoughts would be really helpful.  I haven't heard from the buyer yet about what he wants to do.  Would it be worth trying to head off problems by getting someone in to look at it straight away, or should I sit tight and wait to hear.

user1977

Most people on this forum are looking for "help" of one sort of another - better to have a more informative subject line.

verytired11

user1977 said:

Most people on this forum are looking for "help" of one sort of another - better to have a more informative subject line.

ha ha I thought that after i posted.  I will try to change it if I can....

davilown

There looks like there’s a lot of splash back there - have you checked that the guttering at the top is not blocked? Stand underneath when it’s raining heavily.
Alternatively, are either of the 2 joins visible in the picture leaking?

verytired11

davilown said:

There looks like there’s a lot of splash back there - have you checked that the guttering at the top is not blocked? Stand underneath when it’s raining heavily.
Alternatively, are either of the 2 joins visible in the picture leaking?

Thanks, yes I checked the guttering and it;s not blocked.  Thinking about it i wonder if the guttering needs to be wider.  I now have a loft extension with quite a lot of extra guttering above this so maybe it can no longer cope with the extra water coming through.  I will need to check the joins again - I tried looking yesterday when it was raining but it's hard to tell when everything is wet.  What is the best way to check this?  Everything looks dry inside, so i think you are right that it may be a splashback problem.

theoretica

As well as looking carefully next time it rains pop two identical bowls out - one in the centre of the problem area and one along a bit out of the marks and see if they collect notably different amounts of water.  That would confirm it is an outside issue and not anything inside.

verytired11

theoretica said:

As well as looking carefully next time it rains pop two identical bowls out - one in the centre of the problem area and one along a bit out of the marks and see if they collect notably different amounts of water.  That would confirm it is an outside issue and not anything inside.

Thanks, that's a great idea 😊

JJR45

At a guess the pipe is blocked up at the junction going back into the house. When it rains heavy it backs up and comes out of the joints of the pipe.
Moss is the usual culprit.

verytired11

JJR45 said:

At a guess the pipe is blocked up at the junction going back into the house. When it rains heavy it backs up and comes out of the joints of the pipe.
Moss is the usual culprit.

ah! interesting, thank you, i will investigate further.