White Powder on Bricks

[Franklin Gingrich]

In <313EB7...@sas.upenn.edu> Eby <ebas...@sas.upenn.edu> writes:
>
>Hello:
>
> Does anybody know what the white powdery stuff on the bricks are
? The
>front of my house is built with red bricks. This winter I noticed that

>some of the bricks have a coating of white powder. It looks as if
>somebody rubbed a piece of chalk on them. However, it is really hard
to
>remove the stuff. I presume it is the salts which have been washed out

>of the bricks by rain but I am not sure. If you know how to clean it
up,
>please let me know. I'll be grateful. Thanks.
>
>Eby

Yes, salts washed out of the mortar, called "efflorescence". Can be
removed by brushing with muriatic (hydrochloric) acid solution or with
a power washer. With the washer plain water might do the job, but you
can ask around about products to help the removal. Not m. acid in the
washer, of course.

Frank

[Mark D. Weisel]

The white powder is probably soluable salts that did not get bound in the
brick when it was "fired". When the brick gets wet the salts disolve in
the water and travel to the surface where the water evaporates and
deposits the salt, hence white powdery deposits. Perhaps you can seal
the bricks after cleaning.