Understanding Efflorescence: What It Is and What To Look For
What is efflorescence and what does it mean for my home?
When water moves through a porous material, such as concrete, brick, or wood, the naturally occurring salts of those materials (or those from the ground they’re touching) can be ‘picked up’ by the water passing through and deposited on the surface upon evaporation. Essentially, once the water dries, the salt it was holding is left behind. This is called efflorescence: a dry, white powdery substance that collects on the surfaces of walls or foundations. Sometimes, this is simply a cosmetic issue and warrants no further action. But efflorescence can often indicate that there is unwanted moisture passing through the structural materials of the home. Left untreated, this moisture can have a detrimental effect on the structural integrity of these materials.
Via capillary action, water is absorbed and transported through the tiny pores of materials commonly used in home construction. Although seemingly solid, stone, brick, wood, and even concrete are able to transport water this way. When salt from rainwater, groundwater, or the materials themselves is picked up and distributed by the slowly moving water, the effects can be destructive due to an increase in hydrostatic pressure.
When an increase in salt concentration occurs in material, natural forces try to dilute the imbalance by pushing water towards the collection of salt. This natural push of water creates a huge amount of hydrostatic pressure inside the material and can badly damage even the strongest concrete. This happens because the pressure of the influx of water exceeds the strength of the structural materials.
The result of all of this? Damaged or destroyed materials that can fracture and fall apart. This is called spalling.
How do I know if I have efflorescence in my home?
The first thing to establish is whether or not the substance in question is mold or efflorescence. While it’s possible for mold to grow on inorganic substances, like walls and building materials, it is predominantly found on organic, natural materials. Efflorescence, in contrast, will exclusively collect on inorganic materials so white, crusty streaks on concrete foundations or walls are usually a tell-tale sign. Additionally, efflorescence will crumble into a fine white powder when rubbed between fingers and is water soluble. Mold can be any color; efflorescence will always be white, off-white, or yellowish brown. Both efflorescence and mold can result from excessive moisture. Other signs that there might be too much moisture in a home are damp, rotting wood, visible water damage to floors, foundations, or walls, and cold drafts due to wet insulation that is ineffective.
I found efflorescence in my home – what now?
The efflorescence itself is cosmetic and easily removed with a scrub brush, but the underlying moisture issue remains. If your basement walls are coated with efflorescence and you’re experiencing other symptoms of excessive moisture, the 3 Pros team can help diagnose your home and find the best waterproofing solution to protect the integrity of your structural materials.