DIY Doctor UK DIY Forums

I've moved into my house not long ago built in 1900 it shares an alleyway with next door, I've had a damp specialist in and he's said just leave it, I want to make sure it's nothing as it's playing on my mind, basically the paper is curling up at the bottom and tears off easily, and some parts are sticky like wallpaper paste I would like to know if it's condensation or it would be rising damp again, also there is a small tide mark which runs a foot up the wall but it's dry in most places and only sticky in a few places, any suggestions? Ps the ride mark seems to have dried out and as you can see near the plug socket it's sticky, and wallpaper came off with ease and felt like the walpaper was sticky on the back, but if I scratch the top layer of stickiness off it's bone dry underneath.

And breathe

Tried uploading photo but I can't, also mustiness just old plaster smell

it could be the material drying out, You could wait and see what happens, or get a dehumidifier to dry out any moisture.

Ok
First of all there is no such thing as rising damp, it is a myth. This is not the problem and never was.
The problem you have is condensation building up behind the wall paper.
The other side of the wall is a cold entry, which means a cold wall. When you have the warmth of your house hitting the inside of this cold wall you get an out break of condensation. This condensation would evaporate if it was not trapped behind your wallpaper. The bottom of the wall is the coldest and therefore will be the wettest.
Without getting into to much detail, old houses were originally designed to breath. VISIT http://www.heritage-house.org/pages/man ... dings.html.
for more detail.

The solution is simple and cheap
Remove all the wallpaper and paste.
Repair or re plaster the wall if nessessary.
emulsion the wall using a breathable paint.
(Preferable a lime wash. Visit http://www.mikewye.co.uk/mikelimewashing.htm . they supply breathable paint for old houses)

This will allow the condensation to evaporate. the problem will disapear.

I have a similar issue with a cold internal wall. It has been covered by dot and dab plasterboard and I am getting damp where the dots and dabs are - as this is where there is a thermal bridge between the wall and the plasterboard. Warm humid air in the living room is condensing on these cold spots. The other side of the wall is the kitchen, again the wall has been dot and dab plasterboarded. On this side of the wall however there is efflorvessence (if thats spelt correctly) so there may be salts leaking through (this house was practically derelict when i got it - no windows or doors for over a year and much of the brickwork exposed.

I was looking at Permagard to use as a neutralizing wash to clear the hygroscopic salts - however looking at its coshh sheet it is just diluted acetic acid. Acetic acid is ethanoic acid = non brewed condiment (chip shop vinegar without the brown colour) I have bought a litre of 99% acetic acid on ebay which I will dilute down to make a cheaper version of permagard.

I think from your post your wall is directly plastered - i.e not plaster boarded either on batten or using adhesive. In my situation I am thinking of putting vents in the top and bottom of the plasterboard to promote an air flow in the interstitial gap which hopefully will remove any moisture. Have you considered putting a thermal barrier between the alley wall and the room so the condensation cannot take place?

In hindsight I probably should have done that, my exterior walls in the same room had 80mm of kingspan, followed by a battened 25mm air gap & then plasterboard and they have no sign of damp (building control made me bring the victorian walls up to current thermal rating as I had removed more than 50% of the plaster during the renovation)

apedale builders,

What nonsense to deny rising damp.
Rising damp is merely another name for capillary action - do you deny capillary action?
How do trees gain their moisture? Was Einstein wrong ( his first paper was on this subject)?

Take a piece of toilet paper, touch one end into a saucer of water and watch the moisture rise. That is rising damp - moisture rising through capillaries.

Your reference to the limewashing site is also nonsense - nowhere does that site recommend doing what you suggest?
"emulsion the wall" ? Emulsion an interior wall and then apply plaster or sand and cement over the emulsion and then accept payment would be cowboy building at its best.

Unless you have experience of a subject then its best to listen and learn. If you identified as a DIY'er then fair enough but you claim to be a professional builder and make loud confident claims such as: "That is not the problem and never was." How do you know, how can you know?

I'm harsh because your glib rubbish could cost people money, grief and disruption.