Wood burning stove leak

[cl2702]

Hi, we moved into our house a couple of years ago and there was already a wood burning stove in the living room. We recently had some brick slips installed on the wall behind the stove. Since then, we have had water leaking in at the point where the flue/chimney pipe goes into the wall to vent outside. The water is a brown colour so I’m assuming that means it must be coming down the flue?? There was never a leak before the brick slips were installed. The people who installed the brick slips were from a heating centre and HETAS registered. They’ve been out twice since the leak started to try and fix the problem but nothing they have done has worked. I think they’re at the stage now where they’re not really sure what the problem is so I’m trying to figure it out to see if we can fix it instead. I’ve attached some photos to try and show more clearly where the water is getting in...does anyone have any advice on how/where this water is coming in?? Any help massively appreciated. I’m hoping to avoid having to take all the brick slips back off again but it’s looking more and more likely that we’re going to have to in order to sort the leak ☹️
 

Thank you in advance to anyone who can offer some advice or help. 

[ProDave]

Did they alter the flue?

 

i.e. did they pull the flange of the flue forwards to allow for the brick slips, or did they leave the flue untouched and fit the brick slips around it?

 

It is almost certainly condensation inside the flue running down and leaking out.  What was on the wall before?  Are you sure it was not leaking but just not so noticable before?

[Cpd]

32 minutes ago, ProDave said:

It is almost certainly condensation inside the flue running down and leaking out.  What was on the wall before?  Are you sure it was not leaking but just not so noticable before?

I have had the same problem in one of my houses, the joint that leaks on mine is just behind and up inside the chimney and will be a massive pain to fix.... it gets worse is very cold weather as more condensation builds up, it also gets a lot worse when the liner has not been cleaned for a while.... this is because the fire is not burnt hot enough by the occupant and soot builds up in the chimney and then as the chimney is not insulated (old stone chimney)  condensation builds up runs down the inside of the liner, mixes with the soot and leaks out the dodgy  joint.... and then runs down the outside and down my wall just like your photos ! The solution for mine would be.

replace the liner And fill around it  with vermiculite, try and get the users to but the fire hotter. 
 

 

[Mr Punter]

Maybe this was condensation originally running down into the stove and now maybe the join on the pipe got moved slightly and it is finding an exit point there.

[cl2702]

ProDave-they had to remove the stove and bottom part of the flue to fix the brick slips. When they reattached the flue I think they had to add a short extension so that there was a large enough gap between the new brick slip wall and the back of the stove?? I’m assuming this must have something to do with the problem because the leak is coming through at the point where they reattached the stove. We couldn’t figure out where the water was coming from as sometimes it was coming through when it was raining heavily but then the guys who came to try and fix the leak told us to use the fire to try and dry everything out and then water was coming through after the fire had been on a while but the weather outside was completely dry. So it would make sense for condensation to be a cause if the problem. Before the brick slips the wall simply had a large sheet of fireproof material on it but I’m sure there was no leak before. I notice just about every minor issue with our house (much to my husband’s dismay!!) so I’m pretty sure I would have noticed a line of water on the wall before. 
 

With the condensation, is there anything we can do about it? There’s quite a bit of water so it’s not something I think we can just leave??

[cl2702]

Mr Putner-thank you for your reply. Someone else has mentioned condensation which would make sense as the water isn’t always coming through when it’s raining...it’s sometimes when it’s dry outside ambit we’ve had the fire lit too. Do you know if there’s anything we could do to secure the new join so that the water doesn’t get through there?? Or would this be something we’d need to get the guys from the fireplace centre to sort for us?

[joe90]

They didn’t seal the joint properly when re installing the stove, however, condensation etc is a problem and probably best to do what @Cpd says above by insulating the flue.

Edited December 27, 2020 by joe90

[PeterW]

@cl2702 have you got any better photos of the whole of the internal chimney area as I’m struggling with this - does the stove have a dogleg at the top to get through the wall ..??

 

I wonder if they have used a reducer and it’s not sealed properly and you’re seeing the issue now as condensation is pooling at the bottom and leaking where before it ran straight into the stove. 

[cl2702]

Thank you so much to everyone for your replies. The guys from the fireplace centre never even mentioned condensation and said it must be rain getting in from outside! Thank goodness for forums like this! 
 

@PeterW I have added some extra photos below. Do these help? If not please let me know and I can take some more. The leaking water also seems to have made the pointing/mortar surround the flue damp and discoloured too, even though no water is directly leaking onto this area (see photos below). Could this mean the water is seeping in behind the brick slips as well?

[PeterW]

Looking at that they appear to have pushed the extended piece in then put the connector inside the new liner. That is going to leak and is the wrong way round. Every piece should have the next one up inside it. 
 

I would get them back, get them to take out the cement around the pipe and redo it properly. When was it last swept out of interest ..?

[cl2702]

@PeterW It was last swept just over a year ago. Thank you for your help. We’ll contact the fireplace centre and ask them to come out again and hopefully finally get it sorted! 

[SteamyTea]

Thank goodness that wood burners only produce life giving natural wonders.

Be dreadful if the flue allowed creosote or carbon monoxide to enter the house.

[cl2702]

@SteamyTea It’s sometimes difficult to tell the tone of a message when it is via the written word rather than spoken...please could you clarify your advice? We only used the stove after the people at the fireplace centre told us we should and stopped again as soon as we noticed it was still leaking. We have a carbon monoxide alarm which fortunately hasn’t gone off whilst the stove was in use. But we also have 2 young children...do I need to be worried about the impact on them of using the stove? We won’t use it again until the fireplace centre have been out (again) to try and sort the issue. Is creosote something I need to be cautious of?

[joe90]

@cl2702, steamy tea is a member of the “don’t burn wood brigade”.

 

I recently got called to a neighbours woodburner that was leaking like yours (but much worse) and the flue liner had the joints the wrong way up, so black condensation was running out the joins. Should be female joints face upwards.

Edited December 27, 2020 by joe90

[SteamyTea]

@cl2702

Rather than me give you the low down on WBS, have a quick Google about particulates and other problems with them.

It is the unseen pollution from them that is the main problem.

[cl2702]

@joe90 Thank you for clearing up the meaning of Steamy Tea’s comment! And thank you very much for your feedback about the issue with our leaking flue. Fingers crossed we will be able to get it sorted with the advice from this forum.