The fire at the pulp factory and the sawmill in 1896 destroyed nearly all the wooden buildings on the factory site. Only a few mills and Sahala on the south side of the rapids were spared. From the old factory only the brick-built bleaching plant was left. The new factory was built completely in brick, and both the material and the scale of the building was not matched anywhere else in the area.

Soon after completion of the pulp factory, the paper mills of Patalankoski and Hovilanhaara were built on the east and west banks of the rapids. The completion of the mill, and also the Rekolankoski groundwood mill, enlarged the area of industrial buildings on the north bank of Koskikeskinen as well, although a small water-powered sawmill had operated there towards the end of the 1800s.

The start of paper production increased the transportation of raw materials and finished products. An internal railway was built on the factory site and the harbour area to the south of the factory was enlarged. Bridges were built over Patalankoski and Hovilanhaara for traffic. The structures connected with the use of hydropower, the dams and the chutes, had changed the appearance of the free rapids for good. The factory had timber stores at the Saukko bend, at Alaja and on the factory site.

The red brick-built factory complex with its chimneys represented typical industrial architecture of the turn of the century. The buildings were designed by Architect Bernhard Blom. Industrial activity spread to the east bank of Patalankoski and to the west bank of Hovilanhaara. Power supplies were no longer totally dependent on water. The factories' three chimneys signalled the increasing use of steam power. Industrial plants, mills and a few dwellings continued to exist side by side in the rapids area. The factory office and new workers' dwellings had been built on the east side of the rapids.

Part of the auditory scene was the factory hooter, which sounded five times a day announcing the start of work, meal breaks, and the end of work. Even in the 1920s, the sound of the hooter is said to have been loud enough to shake everything on the factory site. Clocks as far afield as Juokslahti and Haavisto were set by the factory hooter.