The Sandbag Wall (1 bag deep) calculator computes the number of sandbags needed for a sandbag wall that is (H) high and (L) long where the width of the wall is equivalent to the width of one sandbag (see diagram). Water Barriers Sandbag Walls
INSTRUCTIONS: Choose units and enter the following:
Sandbags (SB): The calculator computes the number of Sandbags Needed for a 1 bag deep wall as shown in the diagram.
This simple act of flooding prevention has saved thousands of dollars from water damage through doorways, stairwells and low-lying windows. Sandbag walls that are one bag deep can be useful in for protection from some projectiles and from some water threats. However, in the even of rising water in creeks and storm surges, the user should consider a sandbag dike if the height is expected to exceed two feet or strong currents pressing against the wall. For a more substantial wall (dike), consider the Sandbag Dike Formula () or the combined functions in the Sandbag Dike Calculator ( ).
It is best to partially fill the sandbags. The recommendation is for one third (`1/3`) to half (`1/2`) full with the bag tied off at the neck. This lets the bag be more pliable (flexible) in the stacking process compacting the space between bags. It also makes the bag more manageable to handle.
Lay your sandbags one layer at a time in tight formation. On subsequent layers, offset the bags in a way that staggers the vertical seems. This is similar to the process that bricklayers employee when stacking bricks. It creates a stronger wall.
Obviously, a sandbag wall is heavy. Consider this when placing the wall. Also, for water protection, it is also advised to wrap your wall in plastic sheets (normal construction plastic). This improves the walls properties for holding out water.
Small walls (1 bag deep) can be used in long rows to prevent surface water movement. As stated above, if water prevention is the primary purpose, the weight (and force) of the moving water are a serious consideration. If the expected level of water rises is above two feet (one foot for fast moving water), ais more advisable.
Sandbag walls are also useful around window wells, basement steps, and in ground-level doorways.