Damp problem!!!

[779dave]

Here my problem, I've just bought a 1896 vic terrace it has osmosis damp course fitted no signs of damp anywhere. Except there is a fireplace at rear of house which had a hole in the wall fire till tonight, there were signs of damp or had been damp due to brown staining on paper underneath the fire which is about 8 inch of floor. Now the fire has been removed there were no obvious signs all looked quite dry. I've pulled back the carpet and the concrete hearth was showing sign of being wet i.e some screed cracked and blown and the floorboards next to concrete is damp and swollen, now I've chiseled the concrete to expose joist underneath they are wet but only on top. I've been under floor and the joist are bone dry and most of the chimney breast, I can't see it being rising damp as it will be travelling up over a metre to be seen above floor.
Any suggestions feel free, I appreciate you taking the time to read this long winded topic.
Thanks

 

[securespark]

So, the hearth is showing signs of damp on the top, but nowhere else?

 

[779dave]

Yep, just on hearth and little up wall I'm wondering if it could be roof/ flashing and dripping down chimney somewhere and bridging across to concrete. I've not been up yet though.

 

[EB1caneyeB]

It would be a good idea to check the breast in your loft (especially if raining). You may find signs of damp on your rafters.
It would be good to check your flashing around chimney stack. To get up on roof and check it thouroughly. If you're not good with heights then use binoculars. The only way you're going to know, for sure, if your flashing is sound tho' is to get up close.

 

[779dave]

Cheers I'll be wondering up over weekend if weather holds out!

 

[securespark]

Is it a first floor fireplace?

 

[pred]

Has your chimney been topped off? please dont get on your roof off a ladder if this is not your line of work, trust me, getting on the roof from a ladder that is securely tide to battons is the easy bit, the hard bit is getting from the roof back onto the ladder.

 

[joe-90]

Doesn't sound like a chimney problem to me, those joists would have rotted away years ago if they'd been wet for decades. Sounds like a condensation issue.