With so many different types of basements, wall coverings, and materials used, discoloration could happen for multiple reasons.
The most common foundations that are seen today are: Crawl Spaces (brick, block or poured concrete), Full head height basements (stone, brick, block, or poured concrete).
What having a discolored basement wall could mean:
As I mentioned discolored walls can mean quite a few things. Depending on the history of the house, these stains could be insoluble materials like oil, paint, ink, or anything else that can be washed out of a porous service. The more common cause for discoloration of a floor or a wall is water or fire damage.
Water damage leaves residues behind like efflorescence that is much like a fine powder. Efflorescence is simply the left over minerals from water that has evaporated from the service. Brick or stone foundations that have had plaster laid over it to produce a smooth finish to the wall could also soak up the water, mold, rot and flake off. During this process the plaster will change color. Browns, yellows, oranges and greens are typical to see on a plaster that is coming in contact with water.
Same basic rules apply to the floor.
If you think you have water or fire damage in your home or basement, have your home inspected by a professional to see if there are any possible damage issues that need to be corrected. If your foundation is in fact leaking, or allowing water into your basement, consider correcting any foundation issues that need repair and hiring a basement waterproofing contractor to fully protect the basement from future floods.
Related Reading and Links
Read about the Top 6 Basement Mistakes that contractors and homeowners make. See what other readers have asked in Safe'n'Dry Basement Blog's Reader Questions Section
Ask Jacob A question Directly on Pioneer Basement's Help Forums!
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