A staircase for a London home currently being fabricated by Trappen Smet in Belgium. The z-form stair treads and risers are cut from European oak, as is the wreathed handrail. The image above shows a transition piece of the handrail in place, ready to be carved into shape.
The inner string is recessed from the edge of the stair to allow the slim z-form of the treads and risers to be expressed from the side and from below. The string itself (cut from beech) is curved on its underside as it transitions into the soffit. This makes the overall depth of the stair structure read as slimmer, thus making the stair appear lighter and more elegant.
As the string curves into the underside of the stair, a shadow gap is introduced (mocked up here with another piece of timber). This shadow gap will appear like a ribbon following the line of the twisting stair up through the house. This shadow is also functional, it provides a transition between the timber and the plaster to avoid cracking.
The image above shows the tight turning inner string at the 'eye' of the wind.
Shadow gap formed at the outer edge of the staircase against the wall.
Pellets produced from sawdust and used as fuel to heat the factory.