Damp? not sure.

[craig1]

Hello,

My house was built around 1900. In the dining room I have just

recently noticed what looks like a damp patch just above the

skirting board about 600mm long. Damp being that the wall paper

looks wet?

This seems strange as the wall is internal. The wall divides the

pantry from the dining room.

Advice would be appreciated.

craig.

 

[JohnD]

where is the nearest radiator, tap or pipe (including pipes under the floor)?

 

[joe-90]

It doesn't matter whether the wall is internal or not. Damp produces hygroscopic salts in the brick which suck up water from the earth via caplillary action.

 

[craig1]

Just checked for water pipes using a detector. doesnt seem to be any

around that area. The old tiles on the pantry floor seem to be damp also.

What do you think?

 

[Softus]

It doesn't matter whether the wall is internal or not. Damp produces hygroscopic salts in the brick which suck up water from the earth via caplillary action.

 

[craig1]

Hello thanks for the replies.

Wondered if there was any product available which I could apply to this

area myself to prevent the damp or is this a specialists job?

thanks.

 

[JohnD]

you need to identify the cause before you apply a cure. Pull the skirting board off and see if the stain appears to be coming from underneath. You may also need to take up a floorboard or two. If the stain is semi-circular or triangular, start looking at the centre of the base. Also take off any wallpaper over the wet patch. Look at both sides of the wall.

If there is no sign of a leaking pipe or a dripping sink causing it (and pipes buried in concrete floors often leak) then look to see what sort of damp-course the wall has. depending on age of house, it might be a plastic layer between the bricks about 200mm above ground level, or a bituminous layer, or slate, or nothing. Look to see if it has been damaged or bridged, e.g. by plaster or raising the floor. If you find a lot of rubbish or rubble under the floor, shovel it out.

You may get a better idea of where the damp course is (if any) by looking at the outside of the house.

The wate main probably runs under the floor between the stop-cock probably where the front gate used to be, and the rising pipe probably in a corner of the kitchen.

Can you post some pictures?

p.s. to see how wet the pantry floor is, tape some tranparent plastic sheet tightly to the floor and see if water forms on it in a day ot two.

 

[craig1]

Thanks for the reply,

Removed the skirting. There is a black rubber membrane running

along the length of the wall. At the foot of the wall on top of the

membrane there is a course of bricks with two holes in each brick.

The plaster then starts above the first brick. Havin felt the

wall/plaster it doesnt seem to be damp in the area in question?

Havin pulled back the paper slightly the wall feels really sticky

but the plaster isnt soft or crumbling. Not sure if its damp..

Not yet sure how to enter images onto the site.

 

[JohnD]

//www.diynot.com/forums/viewtopic.php?t=73320

 

[craig1]

Hello,

The cause of the damp patch on the wall paper must be connected

with the Pantry floor. There are reddish coloured old quarry tiles

on the floor in the pantry which are deffinately damp. I can see the

damp and also smell it. Is this common with old pantry floors.

Will the tiles need to be taken up to prevent the damp or is there

a product which can be applied?


Advise would be appreciated...

craig.

 

[Nige F]

Hello,

damp and also smell it. Is this common with old pantry floors.



Advise would be appreciated...

craig.

My butler informs me, that this scenario is not unlikely

 

[craig1]

Well thanks very much you'v been a great help?

 

[JohnD]

In an older house, the pantry is often intended to be cool and damp, to keep food fresher.

Even if not intentional, an older house with a tiled floor will often have no damp proof membrane under the floor, so it will be damp.

Furthermore, an older house will often have leaking pipes under the floor, adding to the damp.

In your case, it sounds like previous attempts have been made to deal with the damp, and not succeeded.

All in all, if you have an older house with a damp solid floor, the only reliable way to cure it is to dig it out, look for any leaky pipes, and relay a new one, with a DPM and preferably also an insulating slab (this is fairly easy and common these days).

If you do this in the pantry it will be noisy and dusty but not take long. (a good local builder, recommended by friends or neighbours, whose work you have seen, will find it easy)


p.s. unlike Nige, I have had to cut down on my domestic staff, and often go into the servants quarters myself.

p.p.s if you try to cover up the damp, it will most likely just come out somewhere else.

 

[craig1]

Cheers john, i'll get a builder to sort it.

 

[JohnD]

great

If there actually is a leaky pipe, when he digs out the old floor, the hole will slowly (or quickly) fill with water.

If so, don't let him lay a new floor without finding and fixing the leak.