Brick efflorescence

[R. Levor]

I have a brick walkway about 10 years old leading from my porch to the street. The first half is under a carport, the rest in the open. We never had efflorescence before. Since the recent heavy rains in L.A. there is a huge volume of it on the bricks and a little on the concrete driveway under the carport, which was mostly dry, and none in the open areas. Can anyone say why this would be happening now? I am brooming it off often, but it comes back as thick as light snow. I'm debating using dilute acid, but I'm not sure that will solve it. Thanks.

Bob L.

[tbasc]

Check the BIA (Brick Industry of America) web site. TB

[Art]

I would stay away from using acid on it.

[Roger T.]

As other posters have noted,

has a good summary of causes of efflorescence. Heavy rains are indeed the cause, as with unusual rains comes reactivation of groundwater flow, and fomation of springs that may or may not be long lasting. Springs themselves can carry salts that evaporate out at the brick surface, leaving soluable salts behind. The water flow can also dissolve salts from whatever base was installed as an underlay for the walkway. If it is mortared, the salts may well com from mortar or underlying cement, but could also be from many other sources. Even the groundwater itself may be hard, leaving salt crystals on the surface. Overall, it is mostly a nuisance. Just keep the brick swept, and wash it off with a nozzle from time to time. I wouldn't use acid.

[R. Levor]

Thanks for the feedback, everyone!

Bob L.