How much plaster to take off after rising damp?

[MacLaverty]

125 year old Victorian terrace and had penetrating damp on external wall, cracked soil pipe now fixed, and damp/ salts coming through a small amount into internal lounge wall. Stripped paint off but salts still appearing through plaster.

I have now chipped away the smalls section of plaster expecting to see brick but I have come across a slab of concrete on one side and some black crumbly stuff on the other. Having looked behind the black stuff, I can see the red brick about 1.5inches back.

In order to fully let that part of the wall dry out, can I let it dry out as is now the contimainted plaster has gone for a few months and then re-plaster with salt resistant plaster?

Or do I need to fully strip it back to brick, take concrete and black stuff off, which will create a gigantic hole to then have to fill back in before plastering?

 

[ree]

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[foxhole]

Once damp problem is resolved it can take many months for salts to stop leaching out .

 

[MacLaverty]

Once damp problem is resolved it can take many months for salts to stop leaching out .

So is it just worth leaving it as it for a few months and then re-plaster once salts stop or do I need to strip it the other 1.5 inches back to brick which I really don't want to do to let it dry out?

Also, would I use regular plaster to repair the whole or could I use tanking slurry as well to make that part of the wall waterproof or would I just be pushing the issue elsewhere?

 

[Harry Bloomfield]

Just click on the name, and select 'ignore'.

(Ed.)

 

[MacLaverty]

Whilst on a similar topic, I have recently taken off a skirting board and taken a big chunk of plaster off with the board. The hole isn't square but it's around 30cm long, 10cm high and ranges from 5mm - 12mm deep. Am I better off using a big gap filler like Ronseal Smooth Finish Big Hole Filler 1.2 Litre https://amzn.eu/d/7yxfdH6

or something like a one coat plaster, https://www.wickes.co.uk/British-Gy...VbZNQBh1qTwr3EAQYAyABEgKOcvD_BwE&gclsrc=aw.ds

 

[JohnD]

It's not very deep, so Joint Cement will do it.

Fill once, slightly recessed, then a final thin skim, pressed very hard. This is a good way to fill and cover any cracks or blemishes that might occur.

Never overfill above your intended finished surface. If you do, shave it off before it sets hard.