Damp / Condensation on Party wall

[SALL2009]

I have a bit of a damp problem with a house we have purchased and was wondering if someone could offer some advice.

The wall to the front of the house shows very minimal condensation marks right at the very bottom of the paper and the rest feels fairly dry.

The front lounge also seems dry.

however the party wall in the rear lounge has clear damp / wetness. Any ideas on how to investigate the cause? I am planning on taking the paper off on the next visit to get a better idea of the issue.
Any tips on what what to look at would be appreciated.

 

[JohnD]

What makes you think it is condensation? More likely a plumbing leak.

Is it a concrete floor, or wooden?

What is on the other side of the wall? A radiator?

Where does the water supply pipe run?

 

[SALL2009]

The other side is the neighbours property, so probably have to ask them.
As far as i am aware it is wooden floor.
Also need to chase the water supply, it is metered so i guess I could try to check the units when not in use.

 

[^woody^]

What's that pier, the old back wall and an extension behind it? A soil pipe boxed in?

That looks like salt from rising dampness.

 

[SALL2009]

No extension. This is the original through lounge. The pier is between front lounge and rear part of the lounge.
No soil pipe in the pier either.

This is a party wall from the original house and neighbours house is on the other side.

If it is rising damp, what would we need to do to remedy it ?

 

[Ian H]

Could be a drain leaking into the subfloor.

 

[Leofric]

If it is rising damp you would need a dpc installing , chemical injection dpc possibly (other types of dpc are available )

 

[JohnD]

start by lifting the carpet to see if the floor is wood or concrete.

If wood, take a few boards up and look for signs of damp underneath.

 

[Balls green]

Could be lots of things but I very much doubt it’s rising damp. Condensation usually happens at the base of inner external walls . High humidity also could be possible problem.(no air ventilation)Old buildings need to breath and most modern plasters and cement renders can also cause problems as they don’t let old pourus bricks breath. Cracked drains and sub floor air bricks letting rain water in is also cause damp like issues. Wouldn’t go spending thousands on dpc. Good luck

 

[^woody^]

This is the original through lounge. The pier is between front lounge and rear part of the lounge.

That's a massive pier to be an ex-dividing wall. No reason for it. Was it a chimney, has it been built retrospectively?

The chances of getting condensation on a warm party wall in the front room are very low - if any chance at all. Unless you also have condensation all over the place. Any white salts are from water coming out of the wall not sitting on the top.

 

[Leofric]

Any white salts are from water coming out of the wall not sitting on the top.

yes , efflorescence due to rising damp like you see below the dpc on the face of brickwork on external walls.

 

[KenGMac]

How about a quick trip to B&Q and purchase a damp meter?

Even the cheap ones can detect the presence of moisture and the spread of same?

 

[SALL2009]

Just lifted the carpet and the floor seems damp. The rear lounge is quary tiles and the front wooden.

Now would this be a leak in the floor or just caused by covering a floor that shouldn't be covered.

 

[SALL2009]

Underneath one of the tiles. Can these tiles ever be covered?

 

[JohnD]

certainly a leak. I observe radiator pipes in the region of the wet patch. Start by investigating that.