How did white get on our red brick building.

efflorescence?? (it's a whitish powdery deposit that appears on brick or stonework sometimes, we see it on some brick homes here in the south)

....if Amanda says so !

Since photo's can't be posted with this archaic system, I suggest you go to someplace like www.diychatroom.com where photographs can be posted and people can see what the problem looks like.

> efflorescence??

First thing I thought of.

I must say JohnB your posts are NEVER:

-NOT helpful
-time wasting
-babble

(nor platitudinous)

I checked on this and Amanda, your response makes sense. This is part of what I found.

Efflorescence is a crystaline deposit on surfaces of masonry, stucco or concrete. It is whitish in appear­ance, and is sometimes referred to as "whiskers". Efflorescence has been a problem for many years, and is a topic of much controversy. The formation of these salt deposits are not mysteries. They are, for the most part, water-soluble salts that come from many possible sources to mar and detract from an other­wise beautiful and serviceable structure. First of all, there must be water present to dissolve and trans­port the salts. Groundwater is often a source of efflorescence. For water to carry or move the salts to the surface there must be channels through which to move and migrate. The more dense the material, whether it be brick, stone, stucco or concrete, the more difficult for the water to transport salts to the surface. Conversely, the more porous the material, the greater the ease with which salts are transported and deposited. Salt-bearing water, on reaching the surface of a structure, air evaporates to deposit the salt. When humidity is low, the water may evaporate before reaching the surface of the structure, leaving the salt deposit beneath the surface, and unseen. When the humidity is high, water evaporation is slower allowing more opportunity for whisker growth. Growths which project 1/4 to 1/2 inch below the surface have been reported in some areas of the country.

Since humidity has a definite effect on whether or not the salts appear, it can be assumed that efflores­cence is a seasonal problem. The intensity of efflorescence increases after rainy winter seasons, de­creases in spring, and by summer has practically disappeared. This cycle may repeat for months or years, but generally the intensity of the efflorescence decreases in all but very extreme cases, and by about the third year it should be practically eliminated.

The mechanics by which efflorescing salts are carried to the surface of structures by moisture and capillary action through porous materials, is understood. The amount and character of the material deposited varies considerable, depending on the nature and source of the soluble materials.

> so ...... have a maintenance person brush it off

Sure...but it probably indicates some sort of moisture infiltration, and could be symptomatic of a more significant problem.

If I saw efflorescence on a short retaining wall (and, it turns out, I DO have efflorescence on a retaining wall) I wouldn't worry very much. But on a wall up high...I would have the roof and flashing checked out. Maybe not urgently, but in due course.