Saltly powder on brickwork

[oricenap]

I have a few areas around the house that have this white saltly powder on the brickwork.
The house has a damp proof course and gaps in the brick work for ventilation, but where is this stuff coming from and how do i fix the problem and clean up this mess.:confused:

Also the house is about 8 years old.

[Auld Bassoon]

I believe that it's called efflorescence . See here for some more data.

[ausdesign]

Being 8 years old the salt crystals tend to indicate that the vapour barrier is being breached. Is it a chemical or physical barrier ? Can you see the barrier (plastic)at the base of the weep holes ?
Sometimes with a liquid damp proof course & non diligent brickies, the cavity can have mud dropped in during construction bridging base brickwork to the brickwork above.
Sometimes a roof leak running down the cavity will appear at a weak spot in the mortar - usually through a perpend but these don't tend to leave much salt residue when evaporating.

[Bleedin Thumb]

... non diligent brickies, .

I've called them a few names in the past but never that:eek:

Obvious not one of Al's jobs.


Whats common law for rectification on trade work 7 or 12 years?

[savage]

Might be wrong, but we had a brick retaining wall and some brick work around the spa, the guy told me to expect it to happen. He said not to wash it off as this just sends it back into the bricks, but to brush it off and it will get less over time!. Don't know if it is a similar problem or not!.

[oricenap]

Thanks Auld for the tip and i think i will have a go at fixing the problem

[Bleedin Thumb]

Might be wrong, but we had a brick retaining wall and some brick work around the spa, the guy told me to expect it to happen. He said not to wash it off as this just sends it back into the bricks, but to brush it off and it will get less over time!. Don't know if it is a similar problem or not!.

When I was a nippa my parents got some joker to concrete under their house -old Queenslander.
The effloresence lasted 30 years. I recon the guy used sand straight from the beach in the concrete however I recently found out that there used to be a well under the house so it could have been osmosis that was causing the problem.
As far as fixing the problem Oricnap... can't help sorry.

[savage]

The bloke who did my work lives across the road, so I trust him, as for the salt on my work it is only coming out of the bricks, he said when the bricks are fired there is a small pillar of salt on top of the pile. When this melts, the bricks are fired, one of my old bosses worked for a major brick company and said the same thing, but gave a more technical insight. As for salt in the mortar, I think you might be right if unwashed sand is used.

[Bleedin Thumb]

Yeh savage salt glazing was quite common a while ago in brick making but not so much now. I'd be suprised if the salt could leach out after being fired as it turns to a glass like substance.
With crook sand I guess were at the mercy of the wholesale suppliers/quarries.
You can get your mortar checked by a lab, besides establishing it as the culprit there probably is little point.
I remember reading a good article on effloresence which I think was produced by the company sell the product Xypex (Try a google)
If it is not a machanical problem as Peter Clarkson has described and it is a contaminent problem then I guess the options are
1. Patience
2. Sealing the wall. There are so many products on the market that would be a whole new thread!