Soil Vent Pipe Leaking?

paperclap

Hi all,

Firstly, is this a soil vent pipe? New to plumbing and want to make sure I’ve got the right name! 

It runs from underneath the concrete in our car port, through the fascia and out the roof. It is open at the top. Has some wire mesh over the top, presumably to stop animals getting inside. From what I can see, no other pipes are connected to it (though, may be connected underground?).

When raining, it “leaks” externally.

It isn’t from the join, nor any other location. It is trickling down the outside of the pipe from the top.

I can hazard a guess that it is normal to have a little water on the outside, as well, it is outside. But, it is pooling at the bottom.

Is this an issue? Or, is it seemingly pooling here because the car port roof is covering the rest of the ground?

P.S. Excuse the mess (random door!). We’re renovating.

Thank you.

NSG666

If there's nothing connected to it then it must be rain water as you've implied.
There is probably some form of seal or flashing around the pipe where it drops though the roof that needs sorting - in a heavy downpour the water might get somewhere that it can do damage. It's a bit difficult to tell from the photo but water might be able to run on the top side of the soffit board and get into the wall or rot timber.

paperclap

Thanks NSG666.

I think you’re right. It’s probably the flashing that needs repairing or replacing.

A right pain to access though, as it is above the car port!

Praying there isn’t any rot to the timbers. There’s some staining to the soffit (which you can see in one of the photos).

Bendy_House

Is there a toilet on the inside of the house in that area? It could be a soil vent pipe.

Nat that this matters. Most likely it's rain getting in around where the pipe comes through the roof as said above.

Is that canopy roof strong enough to take your weight? The timbers look marginal at best...

A solution could be to brace the roof from underneath - posts from the floor, acting or spreader boards under the joists in question, positioned around a couple of feet from the joist ends. Then a crawl board of some sort on top, and you should be fine. But don't come crying on here if you end up amongst that junk

(You'll also need to confirm that the corrugated sheets (?) will handle a spread weight without damage.)

Section62

laurencewhymark said:

I think you’re right. It’s probably the flashing that needs repairing or replacing.

A common fault is often found where the upstand of the flashing finishes and there is nothing to seal the gap between the flashing and the pipe.  A 'weathering collar' is often used, but an alternative is a good quality flexible sealant.

laurencewhymark said:

A right pain to access though, as it is above the car port!

Realistically you need to consider (temporarily) dismantling the car port roof to get access.  Other methods will either be more expensive or pose a safety risk.  Attempting to crawl across what might now be brittle plastic is likely to crack it (even if you manage not to fall through it) leading to new leak(s).

laurencewhymark said:

There’s some staining to the soffit (which you can see in one of the photos).

There's more than a small chance that soffit is made from some form of asbestos - so unless you know otherwise (e.g. it has been tested) then care will be needed not to disturb it during work on the pipe, and in any other renovation work you have planned.

paperclap

Thanks all.

The window you see is the bathroom window. Literally directly behind this soil vent pipe is the toilet.

There is no chance this plastic roof will hold my weight!   

As you say, I think I will have to temporarily dismantle the roof, jump on a ladder and gain access that way.

Had a quick look (from afar), and can’t actually see any flashing at all?! There is some moss build-up around it, so that may be covering it.

I believe the soffits do contain asbestos, yes.

Is it best to get a soil vent pipe flashing kit thing?

Section62

laurencewhymark said:

Is it best to get a soil vent pipe flashing kit thing?

TBH if it was me I'd be looking to get rid of the SVP (in that position) as working with cast iron pipe is a nightmare and getting roof penetrations weather-tight is difficult unless you have the right expertise.  This isn't a job where trial and error will work, unless you are Ok with leaving the car port roof off for an extended period of time.

With the arrangement of the pipe and the toilet I would expect to find a manhole close by.  The SVP will possibly have it's own connection to the manhole separate from the toilet connection.  If you can find that manhole you'll get a better understanding of how the drainage works.

Depending on the layout of the drains, lengths of pipe run, etc etc, I would look into providing a new vent pipe in a more sensible location, and/or fitting this toilet connection with an air admittance valve in lieu of the SVP.  The the feasibility of this will depend on what you have, and any regulations specific to your area.


If not, then before buying anything you really need to get 'hands on' to inspect the flashing and check the diameter of the pipe - also whether the end of the pipe has a wider 'lip'.  There are many variations of what might be wrong and what you need to fix it, so checking before buying is almost unavoidable.

Bendy_House

"...or fitting this toilet connection with an air admittance valve in lieu of the SVP."

That's a good call. Once confirmed it's compliant, couldn't an AAV simply be installed in that pipe joint 3/4 of the way up the wall?

Another_Level

What is that vent pipe made of ? seems to be a paint chip on the lower section.  Also the pipe sockets are a particular shape which has been known on pipes containing asbestos 

plumb1_2

I would definitely say that vent pipe is asbestos, (40 yrs exp) so don’t start cutting it etc
it will be the old lead slate flashing around the pipe , best get a roofer to inspect it, and ask them to take photos to show you.

paperclap

Thanks all.

It is most likely (definitely, actually!) asbestos. But, I don't intend to cut, scrape or disturb it in any way. In fact, I want to keep it as is, until we replace all our guttering (maybe in a few years).

Is this not a "simple" case of dismantling the car port where necessary, access the roof, remove the tiles surrounding the pipe, add some flashing (like the link below), re-place the tiles... sorted?

https://www.screwfix.com/p/floplast-end-ventilation-slate-55-170mm/19121?tc=LA2&ds_kid=92700055281954505&ds_rl=1249404&gclid=Cj0KCQjwkIGKBhCxARIsAINMioLKqtkkI9-edyI5uFH-ppuCSe7-IXJ_I0G1eFSQgQZG978dFGl7OAYaAgkqEALw_wcB&gclsrc=aw.ds