Recommendations for installing downspouts state that they should channel water 5 to 10 feet from the base of the building.
Erosion under concrete slab.
To repair you ll need a form.
Voids can lead to a weakness in the slab causing dips in the surface tilting or cracks and breaks.
Concrete slabs can develop voids from a variety of reasons ranging from sliding soil beneath the slab displaced because of a lack of proper compression to water erosion slowly washing away the soil over time.
These two processes develop slowly and are worsened by the erosive behavior of poorly drained water.
Shrub and tree roots excel in preventing erosion way better than grass roots.
Bury an aluminum flashing or redwood or other suitable material a couple of inches deep and about an inch from the concrete edge allowing it to extend above the bottom edge of the concrete approximately an inch.
These cause voids under concrete slabs.
First solve the erosion problem by directing roof runoff away from the foundation.
Whether it be ground water movement drainage rodents or sprinklers when soil is carried away settling concrete is sure to follow.
Soil wash out another common building practice is to run pipes for plumbing under a slab foundation before it is poured.
Cement or concrete slabs for instance do not drain while a patio made of pavers may.
Properly installed gutters and downspouts will effectively channel rainwater away from building foundations thereby minimizing erosion under concrete slab foundations.
This frequently leads to the formation of voids beneath concrete slab foundations.
Filling hollows under a concrete floor is done through a process called slabjacking.
Erosion of soil is a very common problem.
Slabjacking is used to prevent everything from porch floors to patios and basement floors from shifting.
If the pipe is beneath the concrete the structure will no longer have firm dry soil underneath it just mud.
If household plumbing develops a leak it can cause soil under the foundation to wash out from under the slab leaving a void where the slab is no longer sitting directly on soil.
Another issue that could cause erosion under concrete is a burst water pipe.
Faulty plumbing can also contribute to the creation of voids.
Erosion causes depending on its construction a patio is either of limited porosity or not porous at all.
How to fix erosion under concrete slabs.
The accumulation of water leaking from the faulty pipes underneath building structures will trigger further soil erosion.
Improper water drainage can cause the issue.
Soil settlement and consolidation.