Water controlling building block

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG.
1, a preferred embodiment of the invention takes the form of modifications to a standard rectangular concrete block.
Conventionally, such blocks include: an interior vertical longitudinal wall 1; an exterior vertical wall 2; and three vertical webs 3.
The walls 1 and 2 are spaced apart and are parallel to each other with the webs 3 transverse to and spanning between the walls 1, 2 to form a rigid unitary cast concrete block.
It will be understood that the invention is equally applicable to any type of building block having walls and webs which define an interior cavity within the block.
The choice of a conventional block design is preferred since marketplace acceptance is thereby more probable and the invention is more readily understood when a single known design is referred to in the following description and accompanying illustrations.
At least one vertical rib 4 protrudes from each side surface of each web 3.
Each web 3 has at least one longitudinal groove 5 in the upper surface 6 of the web 3.
In the illustrated embodiment each web 3 includes four ribs 4 and two grooves 5.
The ribs 4 are arranged in two pairs of opposing ribs 4 on opposite sides of an associated web 3.
The pairs of ribs 4 are transversely spaced from each other.
The two grooves 5 are located between the pairs of ribs 4, and are symmetric about the longitudinal centreline of the block.
The grooves 5 preferably extend transversely over the upper surfaces of adjacent ribs 4 to ensure that water dripping from a rib 4 of the block above does not by pass the groove 5 as described in detail below.
For ease of casting the outward vertical edges of the ribs 4 are rounded.
This embodiment has been found by experiment to be an easily cast concrete block design which offers adequate impediments to water migration across the side surfaces of the webs 3 and across the upper surfaces 6 of the webs 3.
As most clearly illustrated in FIG.
2, the ribs 4 are downwardly flared such that the transverse width "w" of the web 4 is greater at its lower end w