Chimney breast damp

[MartinB85]

Hi guys and gals,

We moved into a property last May, and on the first day we saw a damp patch that had pulled the plaster away from the wall on the chimney breast in an upstairs bedroom.

The wall seemed dry and there were signs of repair so we had the room full plastered and a damp sealant applied to the brickwork before hand.

Unfortunately a small section of the plaster never looked dry however the plasterer came and checked and advised the plaster had just stained but it was dry. However since, the stain has come through the paintwork and after a storm a few months ago a damp patch appeared just above that at the top of the wall.

We have since had our guttering replaced, however after another storm the patch got worse. We got the guttering company back who advised that the chimney needed repointing and all the flashing needed replacing. That was done about a month ago, at the same time i sanded back the paint work and applied some damp staining for the walls and repainted which seems to have helped. However yesterday i noticed another small damp patch on the joining of the roof and wall and a straight line of brown damp just below this.

We've already spent just short of 3k on the chimney and guttering, the house was built in the 1920's and I've been advised it could be salt in the walls. The guttering company did advise that ideally the roof needed replacing if not at least the ridges as soon as possible.

The chimney hasn't been used in a number of years we've been told so my next plan was to rather get a new wood burner/flue installed as we have been advised this can prevent damp, or to get the roof replaced. We've been told both of these by recognised builders in our area but at the moment we can't afford to have both done.

Any advice on which may be more affective for the wall would be great, we will eventually get both done.

(apologise for the long story)

 

[chappers]

Can you put up some pictures inside and out.
Could be salts but as it got worse after a storm it would indicate a leak especially as it was emanating from the top.
Salt type damp usually appears as a more random pattern staining.
Bear in mind that if the brickwork was sodden behind it could take some time to dry out properly and whilst it is patches may come and go depending on how it is drying.

 

[MartinB85]

Thanks, I'll get some up before and after i've painted on the stain blocker later then you'll be able to see the old stains which was just random blotches and the news ones which have started to appear.

 

[MartinB85]

The pictures of the blue wall were taken before the guttering got replaced the white was taken after the guttering but before we had the lead and pointing re-done on the chimney. As mentioned I have sanded these sections down and put some stain sealant on and so far so good. I'll add the the most recent ones tonight of the bits that have started to appear around the same areas.

 

[vinn]

What does "full plastered" mean?
Penetrating damp "stains" such as you have need the plaster hacking off to brickwork, and then rendering with a 3:1 sand & lime render mix, and a remedial finish - gypsum plaster is useless for penetrating damp.
"damp staining sealant" is also useless.

Why would lead flashing need replacing - its typically re-arranged not replaced.

Chimney flues need sweeping, and venting top and bottom.

You need to go up a ladder and examine the fascia and gutter and then lift a few tiles (slates are more difficult) to see whats happening.
If your roof has underfelt it should be projecting about 30mm to 50mm over the gutter.
You also need to examine the stack, esp the back gutter.

Take pics of everything, and post them here.

How come you've spent £3K on flashing and guttering.

 

[Doggit]

If the problem was in a loft room, then I'd say there was no dpc in the chimney, but being in an upstairs bedroom, I'd suggest capping the chimney with a ventilated cap after you've swept it. Installing a wood burner will do little for the damp chimney, and if it is damp, then get a silicone dpc installed just above the lead flashing, and the chimney sealed with a damp proof coating. If the problem was caused by the roof, you'd have stains on the ceilings rather than the chimney breast.

 

[MartinB85]

Thanks for the info guys. I've taken a look in the loft and funnily enough it looks like the mortar style material oin the chimney stack has deteriorated.

I havnt had chance to get up to the actual roof yet i will so shortly, but i've added some pictures of the side of the roof where the stack is at.

 

[MartinB85]

Had a surveyor round from a very reputable company who took a look at the roof and chimney, and advised me that the work done for the chimney as described has not been not done. On my invoice from them for the chimney work after the guttering was completed it advises, roof repairs, Leadwork, chimney repairs, all materials supplied and fitted and 2 cowls fitted. I've attached the pictures that the surveyor took who advised that the lead has simply been coated with a sealant, and that he's unsure what the chimney repairs were as the pointing still needs doing in a lot of places.
He said there are 3 options.

Get the chimney repaired correctly and that this needs doing wether or not we look at replacing the roof.
Get the chimney side of the house re-roofed as it takes the brunt of the weather is in worse condition than the rest of the roof.
Get the house fully re-roofed.

He also advised that a new open fireplace may help the damp slightly but wouldn't fix the issue.

 

[vinn]

In my post #5 I asked you a couple of questions which you neglected to answer?

Your latest pics seems to show a leaning chimney stack, and roof tiling where the tiles dont appear to be locking into their neighbouring channels.

The flashing and the flaunching has merely been painted over with a bitumen or white paint.

The stack will have to be re-built and new lead flashing fitted.

In effect the roof plane & stack need renewing - perhaps the whole house roof needs renewing?

Whatever, you would do well to sweep and vent the chimney flues - any redundant flues to be vented top & bottom.
Note: having a "fire" in place will do little for penetrating damp such as you have.

 

[Doggit]

Well you've obviously been ripped off by the guttering company, but that's down to you to chase them for a refund.

As to the roof, What you do will depend on your finances, and it seems as though it's a choice between option 2 and 3, but it'll obviously cost more to split them, than to do it all at once. But whichever option you go for, I'd be inclined to suggest they take down the stack, and rebuild it properly, and they can include a dpc as they do it. It won't take much more work for a rebuild, than for a repair and overhaul job, but at least it'll then go for the life of the new roof.

It also looks as though you could do with some sealant under the soffits for good measure, and whilst the scaffolding is up, I'd think about redoing the masonary paint on the chimney breast.

 

[MartinB85]

In my post #5 I asked you a couple of questions which you neglected to answer?

Your latest pics seems to show a leaning chimney stack, and roof tiling where the tiles dont appear to be locking into their neighbouring channels.

The flashing and the flaunching has merely been painted over with a bitumen or white paint.

The stack will have to be re-built and new lead flashing fitted.

In effect the roof plane & stack need renewing - perhaps the whole house roof needs renewing?

Whatever, you would do well to sweep and vent the chimney flues - any redundant flues to be vented top & bottom.
Note: having a "fire" in place will do little for penetrating damp such as you have.

Sorry for not responding to your questions.

The inside wall on the chimney breast side was stripped to bare brick a sealant applied, bonding plaster and then skimmed.

We originally spent 2400 on guttering for the roof and 3 bays windows including the fascias, eaves. We then paid £600 for the supposed chimney work.

Discussions to be had but I think it looks like we're going to go for a full roof, 2 new stacks (there is another one on the other side of the roof). I''ll probably get the masonry redone on that side of the house at the same time.