Leaking chimney, but where is the water getting in? (see pics)

wrote:

your last critique appeared to me to be a general "crap flat roof" broadside so was hoping you could enlighten the OP with specifics taht he could use to bolster his possible arguments with the professhunals who did it - seems all you are picking at is the height of the stack flashing and what may or may not be underneath it...
Jim K
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jim K wrote:

Well all flat roofs are carp, because simple overlapping of waterproof elements will not in general be enough, as water can and does work its way between the layers in any sort of wind.
The whole point of a roof slope is to make gravity work for you against wind pressure.
Typically what you might do for a stack is to create a flashing, soldered together that extends a LONG way from the chimney base
And run the felt up inside it..but then the corners are vulnerable as well.
So you probably end up with some sort of 'soaker' system. a lead layer under the felt, the felt and a lead layer over it, and all raised up at the stack, so that water has to run up the felt under the top lead, then down the lower lead and a long long way before it ends up dripping off the edge of the soaker through the ceiling..so put another layer of felt under hat as well that goes all the way to the flat roof edge etc. And seal it all with flexible mastic and pray.
It's a series of defenses in the end, all compromised by the fact that gravity on a flat roof is just as likely to make water move towards the places you don't want it, as the places you do.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I must congratulate you for your patience in dealing with such an utter idiot. And take any kudos back from you for not having realised it was a lost cause.
He will never grasp that when you have an obstacle like a chimney you have to set the shed to ground the water around the outside.
All he can see is a Band Aid of lead. He will never be able to grasp more than that.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I've taken a bunch more pictures, and can now see that there is definitely lots of silicone in the gaps. I assume the silicone sealant is specified for external use. Does it have a long life?
The most interesting pic is http://yfrog.com/j3sybj which shows a hole with a *bit* of silicon in it.
http://yfrog.com/afn6fj http://yfrog.com/16fj2j http://yfrog.com/9fn4gj http://yfrog.com/msqhqj http://yfrog.com/9hsi7j http://yfrog.com/507oyj http://yfrog.com/jkj7pj http://yfrog.com/6ra1uj http://yfrog.com/bfjojj http://yfrog.com/hq1xhj
I've started running water on bits of the roof/chimney to find out what is leaking, working my way up from the bottom. Nothing has come through yet, but I do see another problem - see this video...
http://yfrog.com/modscn3310z
I'm going to give the company a ring tomorrow and give them a piece of my mind.
Calum
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

seriously silicone in that appication is a bodge, maybe they were "testing a theory" but silicone is *not* the longterm answer to that stack's issues...

keep it cool and logical, common sensical, decide what you want them to do before you ring them, that may well be "just come and look and discuss how you are going to put it right"
was repairing the flaky stack in the spec/quote for the job? if not then ideally they should have told you how sh1t it was and asked you what you wanted doing whilst they are up there, but they could try and argue it wasn't part of of the job quoted and charge you extra to fix.
have you fully paid yet? just puts you in astronger position to get satisfaction before they poss. contemplate "doing one" and leaving you with the problem - and seeing if you can be arsed to chase them for redress....
keep us posted
Cheers Jim K
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks Jim. Luckily I'm not too hot headed. But I will convey my annoyance that the company's site manager said he inspected himself, and he could see nowhere that the water might get in. He just didn't look around the other side. So far I've got on with the company very well, but they are now trying my patience.
The quote was for providing the loft conversion at fixed price i.e. they explicitly took the risk of unforseen circumstances like additional structural work etc. Luckily we haven't paid fully yet.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Perhaps email him a link to your video :-0

Suggestion of tanking a loft room was a bit of an alarm bell to be sure to be sure...

Beware of getting into argument about state of chimney, which may be contributory but reasonably not part of contract, not reasonable to start pratting about with silicone on pointing though, makes it harder to do propery after. Lead work from any angle is clearly indequate, site manager didn`t need to look closely, was it him who suggested the tanking?
Cheers Adam
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In article < snipped-for-privacy@y11g2000yqm.googlegroup

Well I can't say I've ever seen silicone sealant as good as what it can be to point bricks up;!..

What a bodge job this looks. I'd be inclined to put a complaint in writing and recorded delivery and get an independent inspection.
Do you really want this lot back again?..
--
Tony Sayer


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I strongly agree. I would tell them to hold whilst you get an independent surveyor to list all the defects and the remedial work/ cost.
What is going on with those ridge tiles at the edge of the flat roof? I've never seen anything like that before. From your pictures I can't quite work out where the chimney is in relation to that sloping section that leaks under the soffit. If you can do without the chimney it might be worth removing it below tiles and tiling over that section. It would be another area to eliminate leaks. To be honest if it were my roof I'd want the whole lot stripping off and redoing properly -otherwise it will always be leaking somewhere due to the numerous bodges.
Dave.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

despite my usual distrust of profeshunals (esp surveyors) I think dave's surveyor suggestion could be well "on the money" on this one - too many things going on up there for comfort...
Cheers Jim K
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Why don't we all send two halfpennies in and pay for

to turn up and see what everyone else can see, then report back?
I'd love to get him on a roof. But not for long.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

you forgot your pills again?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'd go along with most of that, tho If it were me and it seems that the water doesn't take that long to appear, I'd prolly chop a bit out of the wall where damp and then try a hose at the bottom sides of the chimney and see if thats where its at and if not the top, might just might show up where its leaking...
But as its just been done why isn't the builder sorting this out?..
--
Tony Sayer


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

They are coming back. At one point they were talking about dry-lining inside - definitely not doing that. They appear to have come to the end of their ideas tho, which is why I thought I'd post and see if anyone had any thoughts - which they do! All interesting comments...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

There appears to be very little if any overlap.

Looks very patchy to me, in the larger picture it shows up even more just how naff it looks, especially the area around the stack.
--
The man who smiles when things go wrong has
thought of someone to blame it on.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yes, it's part of the conversion. They've been back once already to look at it. They'll be back again soon...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The Natural Philosopher wrote:

Who's to say the felt doesn't already go up behind the lead? - my bet is that it does, but this isn't the problem.

IME you can't seal a chimney with lead on a flat roof - where they've took the felt up the chimney sides and then flashed over it, they can't seal the corners and this is where it's getting in, that is to say, the felt is split at each corner and doesn't go 'around' the corner in one piece, and as you say, the lead is just covering brickwork at this point.
I wouldn't flash a chimney like this with lead onto a flat roof - it needs something completely different, torch-on would probably be best but not very permanent
--
Phil L
RSRL Tipster Of The Year 2008
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
#1 Examine how the roofing felt turns up under the lead, because as posted I believe you may have a problem there.
#2 Repoint the chimney, SBR in the mortar where necessary.
Absolutely do not dry-line or the moisture behind will produce a string of problems with floorboards, joists, track through any party wall nearby - trying to hide the problem is a recipe for a total disaster that should be obvious and worries me that they should suggest it. Makes me want to examine that roof more closely.
BTW, you can get wireless and wired cameras quite cheaply - it could be useful to stick one in an appropriate position. From the suggest of *wet plaster* in moderate rain I really do wonder about that flat roof re funneling water.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Difficult to tell.
I bought a couple of those elephant's foot cowls like the one you have, decided they wouldn't reduce the amount of rainfall going down the chimney, and took them back. Actually, they may make it worse by capturing water from a larger area than the original pot opening, and making it run down the inside of the pot - there's nothing to make the water running down the outside of the pot (unless you siliconed it on). You could repeat the plastic bag test on this flue (but you can't block the airflow permanently like this).
I then went a bought a couple of these instead: http://www.brewercowls.co.uk/index.php?view=article&catid=8%3Acappers&id %3Astrap-and-hook-chimney-cappers&option=com_content&Itemid although I fixed them in a different way so the strap isn't visible http://www.facebook.com/photo.php?pid 3157&l14418aa8&id19546457 http://www.facebook.com/photo.php?pid 3158&lFe9b39859&id19546457
In theory, rain water going in the pot shouldn't cause any problems. In practice it might because the internal pointing has been washed away over the years of rain exposure without any heating to dry it. Also, if the flue isn't ventilated at bottom _and_ top, it will fill up with condensation, which will soak through the brickwork in time.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In line with the others I can't see quite how the flashing round the stack is working.
On the basis that the CH flue isn't used and your 'one day' could well be a long way away, I would take down the whole stack and seal the roof properly I'd leave a ventilator out of the flue to allow air flow and mark where it is. If 'one day' does arrive some time then put in a stainless steel liner and flue outlet, again properly sealed in. Rob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.