Damp Treatment

[Skavenger]

I have a minor damp problem that I want to remove before fitting a new kitchen. Once I have repointed the externalwall which is partly the cause I need to sort out the inside wall. I have removed some damagef plaster and render I will replace but what other measures do you recommend.
I will repoint the exposed internal brickwork as some of the mortar is missing. Should I treat the exposed brickwork before making good the render if so what with? Some suggestions have been pva, bitumen to a full chemical doc but I don't want to to to that level
Ya
Some pics of the wall before removing some of the render, plaster was blistered at base and render was blown in worst corner - the White wall pic

Washing Machine Corner

• Skavenger
• 20 May 2009
• 3

Water Pipe Corner

• Skavenger
• 20 May 2009
• 2

 

[^woody^]

Once you have rectified the cause, then you can just replaster/re-render the inside.

You don't have to coat the wall with a bitumen or suchlike unless penetrating moisture is the issue. If defective pointing is the cause, then repointing would be enough

The white wall picture appears to be a classic condensation crescent, and the picture with the pipe, if that is a cold water pipe, could be condensation related too.

Have you actually identified the cause?

 

[Skavenger]

Thanks for the reply, this kitchen suffers really badly with condensation in the winter and the white corner probably suffers worse because this was an empty void in a corner next to which sat a Washing Machine so the problem has been caused by both the faulty pointing (inner wall) causing cold air to hit the back of the render and warm air condensing on the cold wall.

The pipe you can see in the other pic is a gas pipe but embedded in the wall behind, which you can just see in the very corner, is a cold supply heading up to a combi boiler on the next floor and a hot water pipe running down from the same. Some crazy fool actually cut these not only into the render but also into the inner brickwork, the render half way up the wall is missing, this was behind a cupboard but I suppose as the pipes were exposed by the missing render condensation could have been running down the cold pipe causing damp a the base? The section of the kitchen is a very old extension which is joined to the main house, because they did not interlink the brickwork the point down the length of the join has come apart slightly but enough I suppose to let in water, this too has contributed to damp in the cavity and will be rectified.

See pic of the missing render (sorry its on its side) where the pipes are, I am desperately trying to work out a way to get these pipes re routed above ground and out of the walls!!

Embedded Water Pipes

• Skavenger
• 20 May 2009
• 1

 

[chriscardiff]

Looking at your first two pics, i've noticed that the plaster has been taken directly to the solid floor,this can allow moisture to track up the porous plaster and break it down. The reason it only travels say 10-12 inches, is that it eventually dries out. Like the other poster said, could be condensation, or a possible leak. Any lateral penetration should be gone now if your re-pointed outside. You will just need to give it enough time to dry out. A good rule for drying out is for every inch of wall you have, takes roughly a month to dry out in good conditions.

 

[Skavenger]

Ah so an occasional minor flood from the washing machine could have been part of the problem!!

I have also removed a couple of bricks near the worst corner, the one in white, and found that the cavity was full to the height of one brick above the kitchen floor level "Bridging the DPC", so after scraping all the skin off of my hands the cavity in this part of the wall is now clear to about 1/2 brick below floor level.

I could also see a spot of daylight through the cavity so more pointing on the outside.

I'll re muck in the bricks with some bricklaying mortar or pre mixed pointing cement that I have and then re-render.

Presumably the render is OK to floor level but not the plaster?

Some before and after pics

Untitled

• Skavenger
• 24 May 2009
• 1

Untitled

• Skavenger
• 24 May 2009
• 1

Untitled

• Skavenger
• 24 May 2009
• 2

I have also included a picture that shows where I have hacked away render that was blown, this is now an internal wall but at one point, 1930 - 1950 ish, it was an external wall, the third layer of bricks are coated with a pale blue substance and the render did not seem to be adhered to them at all? Any ideas why and what should O treat this area with before I render, I was thinking 1-5 PVA mix?

Untitled

• Skavenger
• 24 May 2009
• 1