There may also be a storage floor called cellar below lower ground.
Is there a void under basement floor.
Garage floors show the least visible sign that there is a void under them.
In this situation the lower level is called lower ground the main floor is called upper ground and floors above it are numbered serially from 1.
The void that you are feeling is normally caused by repeated heaving and deterioration of the basement floor slab over many years and some erosion of the sub slab soil.
Installing a tile floor in all or part of your basement lets you have some fun with design while still quickly covering up existing concrete floors.
You can usually tell there is a void under your garage floor by hearing it or feeling it.
When you drive over a void you will hear the shallowness of the space under the floor.
You may also feel a slight tremor in the concrete as well.
Slabjacking is used to prevent everything from porch floors to patios and basement floors from shifting.
Filling hollows under a concrete floor is done through a process called slabjacking.
Sometimes floor number 1 may be the lowest basement level.
In that case the ground floor may be numbered 2 or higher.