Damp Spots

Walls get damp spots but NO ACTUAL WATER is leaking onto the floor

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Efflorescence

Efflorescence -  A white, chalky, crystalline residue on walls.

Efflorescence is a sign that water or moisture was absorbed into the masonry, cement or concrete at one time. The moisture in the masonry walls and floor, has dissolved some of the water-soluble ingredients like lime and calcium. When these minerals dry out, crystals form, leaving efflorescence.

Causes for Efflorescence

There can be a number of causes for this type problem. Some of the would be:

High Humidity – If high humidity is the cause of your problem, the white residue will usually be uniform over a large broad area. Often times, you can see staining up to a certain height on the wall and it occurs at a generally consistent height. The reason high humidity can cause efflorescence, is because high humidity leads to condensation forming on the masonry surfaces. Condensation causes beads of moisture to form on the cool surfaces and is absorbed into the porous cement.

Wall Cracks and/or Failed Parging – Once you get a crack in your masonry walls, the parging that keeps out water, fails. Because the masonry is porous, it will wick in water or moisture. When the moisture dries out, the minerals and other water soluble ingredients that leached out, begin to crystallize. This looks like white powdery stains on the walls and is called efflorescence.

To Remove Efflorescence – Wear a dust mask and wire brush all the loose material off. Using a chemical etching solution will also be helpful. The surfaces should then be primed before applying a sealer. Read the product instructions to make sure all the materials you are using are compatible.

Uniform Dampness along Base of Walls

Possible Causes 

Condensation – Because the bottom of your basement walls is the deepest under ground, the bottom will also be the coolest. On a 90 degree day, the base of your basement walls may be only 60 degrees. That’s a 30 degree difference in temperature! When warm, humid air contacts the base of your walls, it will condensate or shrink. The smaller volume of air still holds the same amount of moisture, actually more moisture than it can hold. The result is little beads of moisture forming on the cool base of the walls and the floor.

Because masonry is porous, it will absorb this moisture and appear damp looking. With enough humidity, the walls can actually get wet and drip, forming slight puddles.

Water Wicking Up From Below The Floor -  Because of accepted construction practices, your basement walls usually continue down, lower than floor level. This is because they rest on the footer and the floor is poured last.

Isolated Areas of Moisture, Wetness or Damp Spots

Possible Causes

Cracked Walls and/or Deteriorated Parging –

When homes are built, builders apply a water resistant coating outside the wall called parging. When your basement walls get cracks, so does the parging. Porous masonry absorbs moisture in through capillary attraction or wicking. This can cause isolated damp spots in your walls.

Blocked Rain Gutters -  Blocked gutters cause all the water draining off your roof, to spill right next to your basement walls. A large amount of rainfall concentrated next to your basement, is the recipe for basement water problems. The soil next to your home becomes so saturated, water then takes the path of least resistance; your basement.

Low Areas Near Basement – Oftentimes, the backfilled area alongside the foundation, settles down and leave lower areas for rainfall to accumulate. This accumulation of water can cause problems inside the basement

Land Sloped Towards The Foundation – If the yard area is pitching towards the home, you are inviting all the surface water to collect next to your foundation. The soil then becomes over saturated and causes water buildup against the basement walls, causing them to leak.

Planters or Retaining Walls Holding Water? – Look outside the problem areas. Check to see if you have raised planters or retaining walls in that area.  These minor structures can cause big problems for your basement by holding and retaining water. They can cause water problems in your basement.

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