Outside and inside walls
On the left of the picture is a tiled bathroom wall. A cut has been made through the wall and its inner structure is visible: beneath the tiles is a white layer of plasterboard. Then comes a layer of wood about a centimetre and a half thick. Next, the ends of regularly spaced horizontal battens are visible. The cross-section of the battens is around 3 by 5 centimetres, they are about 5 centimetres apart. Finally there is another layer of wood about 2.5 centimetres thick.
In the right half of the picture the inside of the future sauna is visible. At the top, horizontal wooden boards form a sloping ceiling. At the bottom, vertical boards cover the wall. At the top of the wall one side of a beam is visible as a single broad strip of wood.