Gaziantep Merinos Mosque — Fluted-Shaft Minaret

A fluted shaft is the detail most often asked for on a minaret and most often executed badly. Flutes cut into render break away at the arrises within a few years; added in plaster, they fall off in the first winter. The right way is for the flute to come out of the concrete itself.

On the Merinos Mosque minaret a fibreglass shell was applied to the inner face of the formwork modules and the flute profiles were worked into that shell. When the formwork was struck, the flutes emerged in the same concrete as the shaft, with a smooth face.

Resolving the flute detail in the formwork

A fluted shaft presents two technical difficulties. First, because the shaft tapers upwards, the flute width has to narrow proportionally; a flute of constant width looks too heavy against the shaft higher up. Second, enough draft angle must be left so that the arrises are not damaged when the formwork is struck. We design the formwork modules around those two constraints.

Base motifs

The base carries a relief border and rosette motifs. That section was cast with formwork separate from the shaft; because the motif negatives were worked into the fibreglass shell, the concrete surface came out finished with no further treatment.