Damp patches on chimney Breast

murphy_joe

Hi, as attached we have started to get damp patches on our chimney breast. We have a humidity device that’s showing over 70%.
does anyone have any suggestions on how to sort this out?

JohnB47

A bit more info might be helpful. e.g, what's above that chimney breast - the loft or another room. Are there any ventilation grills on the front or on either side of the breast? Is the chimney stack above roof level in good order with good flashing all around where it meets the roof tiles?

It looks like the room was recently refurbished and a fireplace removed - looks a good job too. But, especially if the unused chimney pots above are not capped (against rain ingress), there really should be at least one ventilation grill, to allow air to circulate and avoid moisture build up. Are the unused chimney pots above capped? - I mean with a lid that stops most rain getting down but leaves room for air circulation. Just search for chimney cap or chimney cowl - lots of designs.

Oh and 70% humidity is not really to worrisome, in my opinion.

neilmcl

You need to find out where the source of the damp is coming from. First port of call would be your chimney and surrounding roof tiles and flashing.

Lmc74

As said above their should be a ventilation vent where the fire was removed. 

murphy_joe

Sorry we have put a vent on the other side of the chimney breast. We have just removed the old liner from the chimney and replaced the cowl.

murphy_joe

Photos attached. 

The vent is in the hallway that we have just put in. We removed as much soot from there as possible.

FreeBear

JohnB47 said: Oh and 70% humidity is not really to worrisome, in my opinion.

For comparison - Humidity inside my house has been 45-55% over the last 24 hours in the hallway. In the kitchen, it hit 60% in the afternoon (door was open for much of the day). Outdoor humidity has been at ~50% and started rising around 8PM and is now at 72%

An indoor humidity of 70% at ~22°C on a hot day like today is indeed of concern. Open some doors & windows and get some air circulating.

easty

I’m having very similar problems at mines. 

Flashing replaced. Chimney breast painted with some waterproofing stuff. Not getting any better.

Its incredibly frustrating. If this was going to be my long term home, I’d bite the bullet and get the chimney rebuilt, but I only plan to be here another 18-24 months and it’s not worth the outlay.

neilmcl

easty said:

I’m having very similar problems at mines. 

Flashing replaced. Chimney breast painted with some waterproofing stuff. Not getting any better.

Its incredibly frustrating. If this was going to be my long term home, I’d bite the bullet and get the chimney rebuilt, but I only plan to be here another 18-24 months and it’s not worth the outlay.

That sounds like condensation to me.

easty

neilmcl said:

easty said:

I’m having very similar problems at mines. 

Flashing replaced. Chimney breast painted with some waterproofing stuff. Not getting any better.

Its incredibly frustrating. If this was going to be my long term home, I’d bite the bullet and get the chimney rebuilt, but I only plan to be here another 18-24 months and it’s not worth the outlay.

That sounds like condensation to me.

I have a wood burner and flue liner. Would that cause condensation?

How do you deal with the problem??

FreeBear

easty said:

neilmcl said:

easty said:

I’m having very similar problems at mines. 

Flashing replaced. Chimney breast painted with some waterproofing stuff. Not getting any better.

Its incredibly frustrating. If this was going to be my long term home, I’d bite the bullet and get the chimney rebuilt, but I only plan to be here another 18-24 months and it’s not worth the outlay.

That sounds like condensation to me.

I have a wood burner and flue liner. Would that cause condensation?

A stove used on a regular basis would keep the chimney nice & toasty and drive any damp out. A warm wall will not be subject to condensation. So if you have damp patches, you'd need to look for places where rain water could get in - Flashing, flaunching, uncapped adjacent pots..