Is it rising damp? if so what to do?

[fleetfox]

I have two areas of concern in two seperate bits of the house.

1. I have an old yorkist range the chimney of which has been capped off. Around the range (on either side not above) the paint and plaster turns to dust and falls off the wall. Also in more severe areas it bubbles up into a powder and can be rubbed off easily with my finger. the walls are not stained in any way and there is no 'tide mark'. Also at no point does this get above knee height and there are no problems anywhere over the three floors through which this chimney extends. So..... is this damp? if os is it rising damp? and what should i do? As contect the house is over 300years old and so has no DPC.

2. I have another wall (internal) in a different part of the house one side of which has been painted white. The paint of that wall is bubbling in a different way but you can still rub the paint off with you hands. Funny thing is the other side of this wall is totally fine (paint is sound, doest rub off etc). when i rub the paint off this wall there is blue paint beneath, again there is no staining or ride mark. Is this damp? if it is why only one side of an internal wall? If not what is it and what should i do about it.

(If you are interested i have another bugger of a problem posted in the heating section).

 

[dave1953]

The bubbles etc you describe sounds like salts contamination to the wall,they draw water content from the air [efflorescense] and react as you have descibed and yes it probably is a result of rising damp.You would need a competent person with a Protimeter to survey the areas to determine this and to what extent it has got to.
Chimney's, especially back to back,are notorious for damp problems because of rubble infills etc and no Damp proofing company would issue a guarantee to these areas if you went down that route.
Are your walls lime plastered or have they been re-plastered at some stage. Personally I would hack off the existing back to the substrate,two coat waterproofed render and skim finish in the ideal world.If your building is listed then you would'nt be allowed to use this method and a good alternative would be to affix Oldroyd membrane to the walls and lime plaster as existing, go on to www.safeguardeurope.com and you'll see what I'me on about. Hope this helps

 

[foxhole]

Decoration fault could be distemper and is not caused by damp, chimney fault is almots certainly caused by rain penetrating the chimney [poor flashing , missing pointing] then running down chimney, is the chimney vented? it should be.Very very unlikely to be rising damp, no one has ever been able to proove it exists.

 

[ginger100]

Decoration fault could be distemper and is not caused by damp, chimney fault is almots certainly caused by rain penetrating the chimney [poor flashing , missing pointing] then running down chimney, is the chimney vented? it should be.to be rising damp, no one has ever been able to proove it exists.

Very very unlikely foxhole you really shouldn't tell people that rising damp doesn't exist

 

[lostinfens]

I'm with Foxhole on this, a 300 yr old house with a bit of flaking plaster doesn't seem too serious . I wouldn't rush into hacking off & rendering, stick with lime plaster. Old capped flues are notoriuos for damp as Foxhole says, is it vented? Is the stack sound etc?