What are those white and red stains?

aXa News

Efflorescences?

If you have an unfinished basement with bare concrete or block walls, you might notice a strange occurrence that happens over time. You will gradually see an efflorescence, white and red stains appearing on the walls. This visual warning is chemistry at work.

To understand why this efflorescence is happening we have to start at the very beginning.

During the construction of your home, a waterproof barrier was placed on the outside of your basement walls before backfill was pushed in covering them. That backfill is loose, disturbed soil that contains rocks and will never have the compact density of the undisturbed ground surrounding it. As a result, water tends to fill that area first after every rainstorm.

The backfill soil, along with its rocks, will move with every rainstorm. Eventually, the exterior waterproof material will wear away from the movement allowing groundwater to saturate your basement walls. Rainfall in the Northeast averages about 28 to 62 inches a year so wear and tear of that waterproofing will happen sooner than later.

Unfortunately, sometimes a home construction company may not apply waterproofing at all before filling the outside space around the basement with backfill. That means the discoloration of white and red could appear not long after the construction of your home. There is much shoddy craftsmanship out there, and many of our American Dry inspectors have spotted structures that would never pass building code.

We now understand how water saturates basement walls we can move onto the chemistry that takes place between those walls and their exposure to groundwater.

The soil in the Northeast by nature is acidic. The absorption of water and acidic silt (fine dirt carried by water) can lead to the breakdown of lime. Lime is part of the chemical makeup of concrete and acts as the bonding glue in concrete mixtures.

The white and red staining inside basement walls are evidence that the breakdown process is taking place. The acidic soil (acid) and lime (glue for concrete) are opposites. They neutralize each other upon contact, and the lime loses its ability to keep the concrete together.

Your house will not crumble instantaneously, but it will form wall cracks, shift the house, so doors and windows will not close properly, and possibly lift the roofline exposing your home overhead.

How can I stop this destructive process?

American Dry Basement Systems can help you get back the structural integrity of your home before it is too late. We use our propriety SuperSlurry (for walls) and SuperCrete (for floors) to help reverse the chemical breakdown of concrete. Don’t hesitate to contact us for a free, no-obligation inspection and quote. We will not recommend any our services unless it is entirely necessary.