salt on plaster

[MortarThePoint]

Plasterer finished plastering upstairs a week ago and will come back in a month or more to do downstairs. Happy with everything. One thing I have noticed though is some salt on the surface of the plaster. Only on a couple of engineering brick pillars which are between windows. Is this because the only path for the water to leave has been via evaporation at the plaster's surface rather than via being sucked into the blockwork like elsewhere? Make up is Knauf MR plasterboard stuck to reveal with Knauf plasterboard adhesive and primed with BG BondIt. Plastered with BG HardWall and then BG MultiFinish skim. I expect would have had Webber pink mesh here. Catnic corner beads. Possible Bonding Coat was used on the Engineering Bricks, I can't remember.

 

It could be the water from both the plaster and the plasterboard adhesive has had to exit via this small area. Only noticed it today (June 13). Probably plastered end of May. Been very hot for last week, though only risen to ~22C inside. Haven't been in room much so no reason to have noticed sooner.

 

@nod is this normal?

 

 

Edited June 13, 2023 by MortarThePoint

[nod]

That’s worrying 

Will need knocking off and the brickwork spraying with a salt inhibitor 

[MortarThePoint]

8 minutes ago, nod said:

That’s worrying 

Will need knocking off and the brickwork spraying with a salt inhibitor 

 

I hope that's a joke.

 

These are engineering bricks so shouldn't have much salt in them should they. They will be very low porosity so wouldn't it be unlikely to be coming from the bricks.

 

The first picture is about 3cm x 3cm total area, so the salt itself is about the size of a small fingernail.

[MortarThePoint]

Here's another picture 

The pillar is one stretcher wide plus plaster