Inverted T Beam

The cross section to the right shows the finished shape of the mortar if it could be separated from the stone elements and the porous laying course.

The top of the joint has a repeatable finished surface which is visually impressive.

When the mortar is vibrated into the joints, it extends into the top layer of the porous laying course, and under the edge of the stone elements. This produces a profile shape under each joint rather like a rivet head that has been extruded - or an inverted T beam. This T beam is located in the void spaces of the porous laying course, which resists shear forces and allows the layers to act as one.

As these inverted T beams are connected to each other, they provide an exceptionally strong mortar “grid” that physically connects the stone elements to the porous laying course through the inverted T beam.