How to Find Source of Damp Ceiling Near Chimney Breast

[matthussey]

It's worrying how many things this could be. I guess a really big leak is easier to find than something like this?
Is there a proper way to find a leak, like working back from the damp area until you find a cause, or do you just do a bit of trial and error until it stops?

 

[matthussey]

Ok, more possible bad news. I went up during the rain we've just had and couldn't find a leak but while there I turned off the light and happened to catch a little bit of daylight from a different area. We've had no leak there at all but I'll need to get the sorted too. The worse thing was I shone my torch around different areas and I think I've found what seems like it might be dry rot.

It's in a corner on the other side of the roof and in shadow, hence why I'd not seen it before. It looks like grey cobwebs on the beams. I tried the damp meter on the wood there and it didn't actually come up as particularly damp. I was just reading and this sounds like dry rot? I managed to get some of it back when I pulled my damp meter back it seemed like strands of grey cotton (not cotton wool). I'd almost say it was like a large dusty spider web. I've attached a photo as good as I can take one. I'll try to get closer next in a bit. Stupid me disturbed it though so if it is dry rot I've probably thrown it everywhere.

On another note, am I doing the right thing looking for problems like this? My wife spoke to one of her friends and she said she had a patch on a ceiling in a past house and just put a dehumidifier on to clear it. She has something fall off of her roof in her current house and didn't even bother to check what it was or whether it was causing damage. They just leave things until something happens, then fix it. I think that sounds a bit silly, but they sound like they think I'm being silly.

 

[matthussey]

Ok, my builder has just been and he said that the new thing I found was a leak but he went outside and from the ground said the roof looks sound although he'll check another time. He thinks it is an old leak. I tried to do a screwdriver test on the wood (from a screwdriver on the end of a long pole) and I couldn't get it to dig in at all. Obviously it would be better to be there doing it directly by hand but I couldn't get over there. I did manage to get a ball of the grey stuff back and it is very dry with stuff like paper in it (my wife thought it was like grey dusty leaves), plus some strands that are like cobwebs. I've attached a picture. It looks like the remains of insect nest to me, but I don't know what of. We did have a bees nest that exited through the eves near that area this summer but it doesn't look like a bees nest to me. I've got a couple of videos of me rolling it in my hand.

Anyway, I showed the builder the felt slip and he said he'll sort that. He again said the flashing looks like it needs doing and could cause the issue. He said the pointing seems fine and that when he did some previous work on the chimney it seemed good. The flaunching could need doing but he said it would be more likely to cause issues on the chimney breast itself or further down, but that doesn't rule it out. He also said it could just be condensation and said our house did feel like it could be that. He said that if it were moisture in the roof it should move around but if the condensation is in the top around the ridge then that can be a problem.

 

[palaceray]

Joe-90 you may not be aware but you do not have soakers on interlocking tiles, any to re- new the flashings and back gutter along ith the pointing and flaunching would cost a lot more than £250

 

[joe-90]

I didn't notice the tile type. (and I didn't say renew all the lead). £250 should easily cover it.

 

[matthussey]

Joe-90 you may not be aware but you do not have soakers on interlocking tiles, any to re- new the flashings and back gutter along ith the pointing and flaunching would cost a lot more than £250

I'd wondered that after looking at what soakers were. I thought it would be a nightmare to shape them to go under the wavy tiles.

My wife just told me that it's heavy rain so I ran up there and I'm seeing nothing leaking at all. I wonder if the leak may depend on heavy rain and wind to blow it into a particular gap. I wouldn't really call this heavy rain, but we had drizzle for about an hour around lunch time and a more sustained period now.

 

[joe-90]

One thing to bear in mind is that there are over 30 million open chimneys in the UK and they aren't causing problems even though the rain goes down. Therefore if your flaunching has little cracks the extra dribble of rain won't make any difference to the rain that's already pouring down. The same applies to the pointing. Neither of those two is responsible. The best bet is to check where the flashing goes into the mortar course. Over time, lead shrinks and pulls out a little, then during wet weather when the bricks become saturated, the rain runs down the brick behind the flashing and down the chimney into the house. You can get little clips that fit it back in again. (I think they are called Hall Clips). Then seal with fresh mortar or a lead sealant (which in my opinion is better). It shouldn't cost more than £50/60. Go out and look at other chimneys and you'll see that it is a VERY common repair.

 

[matthussey]

One thing to bear in mind is that there are over 30 million open chimneys in the UK and they aren't causing problems even though the rain goes down. Therefore if your flaunching has little cracks the extra dribble of rain won't make any difference to the rain that's already pouring down. The same applies to the pointing. Neither of those two is responsible. The best bet is to check where the flashing goes into the mortar course. Over time, lead shrinks and pulls out a little, then during wet weather when the bricks become saturated, the rain runs down the brick behind the flashing and down the chimney into the house. You can get little clips that fit it back in again. (I think they are called Hall Clips). Then seal with fresh mortar or a lead sealant (which in my opinion is better). It shouldn't cost more than £50/60. Go out and look at other chimneys and you'll see that it is a VERY common repair.

Thanks. I know what you mean. Our next door neighbour has a disused chimney with completely crumbled away flaunching but haven't bothered fixing it.
I'm a bit surprised that I couldn't find any leak yesterday when I went up. I'm trying running a dehumidifier to see if I can at least soak up some of the moisture.

 

[joe-90]

It might be that with a quick burst of rain the bricks soak it up. When they are saturated as in prolonged rain, then it'll start to dribble. It's worth looking at the usual culprits first.

 

[noseall]

Unless the lead has got holes in it it isn't the flashing other than to re-fix it, which would take about an hour. Flaunching is an easy job as is re-bedding ridge tiles. If he can't do it in six hours for 120 quid I'd find a new builder.

Do you know how much it costs to buy a roll of code 4, 12" lead?

Do you know how long it takes or how much is costs to burn a front apron or a back gutter?

You are a clueless joke amongst pro builders Joey.

 

[noseall]

It could be the soakers that sit under the tiles but even if it is, then it shouldn't cost more than £250. It seems to me he's made up his mind to do a 'proper job' at a proper price. Basically, he could well be looking for work and 'bigging' the job up.

There are no soakers on profiled concrete interlocking tiles.

You are a clueless joke amongst pro builders Joey.

 

[joe-90]

Do you know the leadwork is shot? You are a fool of the highest magnitude.

 

[noseall]

Stop dishing out poor advice Joey especially pricing of jobs. You know nothing about our trade. You are a clueless joke amongst pro builders Joey.

 

[joe-90]

That's rich considering you are a Council tenant. If you think a new roof will cure it, then fine. Let the OP find six grand. What do YOU think the problem is Nosey? If it's just the flashing that needs refitting than that is a sixty quid job. It's YOU that knows sweet FA about costing in the real world.

BTW, why don't you repost that picture you posted ages ago? You know, the one where you hit yourself on the head with a lump hammer. (True story btw).

 

[matthussey]

I'm really hoping that I don't need a new roof!