Efflorescence

[garrymum]

Hi

Over the last few months our 12 year old house has just developed efflorescence in the porch (left hand wall and underneath the door).

Is this presence of water / moisture in the brickwork? I'm Hoping that this is due to the longish periods of snow we've over the last few months and not coming from the inside (there are some central heating feed pipes which run down the inside of that wall).

Also, will general path and patio cleaner get rid of it?

Thanks

 

[tony1851]

In new work it's generally the drying-out process, but 12 years old?
Could suggest dampness drying out, but the damp could be from anywhere.
Don't use patio cleaner - the salts may go back into solution, just brush off with stiff bristle brush.
If the dampness was temporary (eg the snow) it will eventally go.

 

[garrymum]

In new work it's generally the drying-out process, but 12 years old?
Could suggest dampness drying out, but the damp could be from anywhere.
Don't use patio cleaner - the salts may go back into solution, just brush off with stiff bristle brush.
If the dampness was temporary (eg the snow) it will eventally go.

Thanks. Regarding the use of patio cleaner. What do you mean by "the salts may go back into the solution"?

 

[tony1851]

The little white fluffy deposits are salts (usually of magnesiun and calcium) drying out on the surface; lick the end of a finger and pick up some of the salt with it and taste it -it will taste salty.

If you tried to wash the deposit off with water, most of the salt will disolve in the water and be absorbed back into the brick. It will reappear when the brick dries out again - this is why it should be brushed off.

If you use chemical cleaners, the effect will probably be the same, but as most cleaners are acid-based, they can also attack and discolour the mortar.

You really need to check where the damp has come from, as efflorescence is more a symptom rather than a problem in itself.

 

[^woody^]

You dont think it's lime bloom then?