[Image: Sandbag Wall]Short Sandbag Walls
For walls four bags high or less, a simple vertical stack can work. Bolster the wall on the dry side every 5 feet with a cluster of bags or by providing other support. You may use the building to support a short vertical stack.
Vertical stacks are used to block doorways also.
Caulking weep holes on brick veneer buildings can slow the passage of water into a building, but water will pass through the brick itself unless it has been sealed or the building has been wrapped. Blocking doors and weep holes is not a reliable flood protection method.
Sandbag Levees
Where you need protection from water deeper than 2 feet, the stack of sandbags should look more like a levee.
To incorporate 6-mil plastic sheeting into the stack, first lay the sheet along the ground where the outside edge of the sandbag levee will be. It should be 6 mils or heavier and three times as wide as the intended height of the levee. As you add bags, bring the sheeting up between them in stair-step fashion.
You can add plastic sheeting to the face of a sandbag levee instead of weaving it between the bags (see diagram). In either case, don't stretch the plastic; it should be slack wherever it isn't completely supported by the bags.
Add height to the levee by adding bags to the inside and crown.
A bonding trench will help prevent the levee[Image: Sandbag Levee] from sliding.
When blocking an opening, the plastic sheeting should overlap the permanent structure at least 2 feet on each end. Continue the sandbagging a couple of feet beyond the opening in front of a permanent wall or levee to get a good seal.