13 Apr How To Build Core-Filled Reinforced Concrete Block Walls

Increasingly building contractors are constructing core-filled, reinforced concrete block walls without installing “Clean-out blocks” at the base of the wall.  And on the later investigation, unsurprisingly, the core is not fully grouted in at the base of the wall.  This is a critical defect, particularly for cantilever retaining walls and parapets, and could be catastrophic.

Your attention is drawn to the following:

1. The absolute necessity for “Clean-out blocks” to be documented on structural drawings for the bottom course of all core-filled, reinforced concrete block walls.
2. A highlighted “Hold Point” note should included on the structural drawing that “The clean-out cavity is inspected by the structural engineer, to ensure it is clear of mortar droppings and building rubble, prior to sealing up and grouting of the block wall.”

Isometric sketches can easily be included on the structural drawings and would be useful in assisting site personnel to understand what is meant by a “Clean-out block”.  The sketches below from Baines Masonry clearly illustrate what is required.

–

–

–