Project 02 / 07

Building with exposed waffle slab

Single-storey building with a large perimeter cantilever and an exposed concrete waffle slab as the interior finish.

Here the structure is the finish. The waffle slab is exposed throughout the interior, so the calculation and the reinforcement detailing had to be worked out knowing that every rib and every drop panel would be on show.

The building is arranged as a horizontal box with a continuous perimeter cantilever that shades the glazed façades. That cantilever calls for a greater depth and more reinforcement than the span between columns alone would require.

Fair-faced concrete does not allow for repairs: the formwork, spacers, joint positions and pouring plan were defined before starting and checked at every pour.

When concrete is left exposed, the reinforcement drawing stops being a technical document and becomes an architectural drawing.

01 Exposed concrete waffle slab seen from below, with the ribs and drop panels in view

02 Interior of the room with the exposed waffle slab and the timber cladding at the back

03 Room with an exposed waffle slab and a continuous window along the façade

04 Side view of the building with the cantilever and the steel support columns

05 The finished room at night, with the waffle slab lit and the timber floor

06 Glazed façade of the building lit at dusk

07 Detail of the waffle slab: the ribs and the solid drop panel where it meets the column

08 Waffle slab seen from below, with the drop panel over the support

09 Panels of the waffle slab where they meet the edge beam

10 The finished room at night, with the waffle slab lit from the floor

11 Interior with the exposed waffle slab and the timber cladding at the back

12 Room with the red back wall, the timber floor and the waffle slab lit up

13 Side view of the room, with the continuous window at the back

14 The room at night from the back, with the continuous window and the waffle slab above the timber floor