I recently completed a new large house (the brick is up 9 mos.)with exposure to wind and rain and have ongoing effervence from the brick. Localy we don’t use a lot of brick and concensus is that it will need to take it’s course untill the salts dissapate. Meanwhile, my homebuyer is upset because the house doesn’t look good. Anybody out there who is familiar with brick with information?
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"Until the salts dissapate...."
FWIW, I see ongoing efflorescence in 50 year + block basements. I wonder how long it'll take to dissapate?
Something's wrong and needs to be fixed; you need to stop the water/moisture migration through the brick.
Bob,
This is very common here, UK, and is NOT a sign of something wrong since it will happen in a wall properly constructed with a damp-proof course, etc.
It is worse if the bricks were wet when they were laid and the wire-cut and pressed bricks are less prone than the commons or stock bricks.
I would be worried if it were happening in a band just above ground-level but not if it is generally across the wall.
Efflorescence is a crystalline deposit, usually white, that may develop on the surfaces of masonry construction. Often it appears just after the structure is completed-when builder, architect, and owner are most concerned with the appearance of the new structure. Although unattractive, efflorescence is generally harmless.
A combination of three common circumstances causes efflorescence:
1. soluble compounds in the masonry
2. moisture to pick up the compounds and carry them to the surface
3. evaporation or hydrostatic pressure that causes the solution to move
If any one of these conditions is eliminated, efflorescence will not occur.
All masonry and concrete materials are susceptible to efflorescence. During construction process, water in the mortar or grout is an available source of moisture in the masonry system. Additional moisture is often introduced from rain or snow. Water-soluble salts that appear in chemical analyses as only a few tenths of one percent are sufficient to cause efflorescence when leached out and concentrated at some point on the surface. The amount and character of the deposits vary according to the nature of the soluble materials and the atmospheric conditions. Efflorescence is particularly affected by temperature, humidity and wind.
Prevention involves several factors, and even when they are followed it may still happen. Removal can range from dry brushing, to using a masonry cleaner, or a very light diluted solution of muratic acid (1% to 10%). Thorough rinsing with clean water. Test areas for compatibility, before any broad application is used. Colored masonry means an even milder clean be used, ( 1% or 2% acid solution). It is often helpful to determine the chemical makeup of the efflorescence so that a cleaning solution can be found that readily dissolves the efflorescence without adversely affecting the masonry.
Three common compounds are: Alkali sulfate, Calcium sulfate, Calcium carbonate, removal of all three have different recommended cleaning methods.
Hope this helps.
A "good contractor" can improve the looks of your house merely by discussing the cost of remodeling.
You seem like a real expert. Thanks for the time you took to help me. I'll be sure to forward your information to the client. Thanks!
Thanks for your time and information. I will share it with the client soon!
The UK and Portland, Oregon have similar weather I suspect. Lots of rain in the winter and sun in the summer. Thanks for the input.
Thanks for your input, it was interesting and helpful.
The same problem sometimes occurs with precast concrete. PCI's advice was basically the same as your consensus .............. wash it (mild acid wash) and let it run it's course. Do NOT seal it.
Edited 4/4/2002 9:45:35 PM ET by jc
Tom,
3 years now and I still occasionally find it under my windows. I inspected the sills numerous times looking for a small pinhole in the caulk letting water/moisture in. After watching a rain one day I realized that rain water dripping off the edge of the row locks and wetting the brick was the culprit. (I'm not puttin' gutters under my windows neither.) It has stopped on all but two windows facing north and I see far less after each rain now. Must be running its course.
We're in Portland, Oregon, nuf said about the rain. Could be the major factor. Thanks for the info.
We were worried about sealing. Thanks for the input.
This site may help
http://www.upchurchkimbrough.com/technotes/efflor1.html
Thanks, I'll check it out.
Tom,
This is common -- some bricks are worse than others, depending on the salts in the clay from which they were made, but providing moisture is not wicking up from below then it is normal and usually weathers off.
The suggestion of a mild acid wash is also a good one.
The mason did was it with acid right after install. We were concerned about too much acid etching the surface of the brick. It is one of the options we have considered. Thanks for your help.