Upper Leirfoss Powerplant

The powerplant represent s an architecture typical for industrial constructions from 1880's to the early 1920's. It is built in 1901 of red brick with  with white decorations and rounded windows. After 110 years it was due for an exterior renovation with new renders and repointing of the red brick wall. Hydraulic lime mortars were used for this renovation.

Trondheim Murservice AS, arch: Gadriel Kielland; Building Owner: Statkraft
Project Date
1901/ 2014

Issues and stakes

The red brick masonry structure was originally rendered with LC-based mortars. In the 1980’s the surfaces were repainted with organic based paints with a low damp diffusion openness with the result of flaking, pulverization of LC-render and frost damages. The lack of maintenance of flashings and roof drains at least during the last 20 years had given big damages in the construction, bedding mortar and renders. This massive penetration of water with following frost damages has followed all the damaged roof drains. The original steel H-beams over the windows and ventilation passages had massive corrosion damages giving expansion of the beams, bulging and cracking of the render. The damages ar typical for these kind of buildings and often seen as lack of regular maintenance.

Upper Leirfoss Powerplant was built to supply Trondheim with power to industry, housings and not at least the city tram. Planning and building the first powerplant in this region- already delivering power to the city in 1890, “Trondhjem Elektricitetsverk og Sporvej” contributed to the electrification and growth of this city. The building is designed by Gabriel Kielland, erected in 1901 and the equipment itself- the generators were provided by Asea Per Kure. Its closeness to the city, producing power from the river “Nidelva”, both the technology and the building is a heritage representing the growth of a national, and still important industry.The powerplant produced power from a 34 meter waterfall, its maximum outlet 85 GWh. This powerplant and its “sister” Lower Leirfoss powerplant were replaced by a new plant in 2008. Already in 1987 these two old powerplants and surroundings were protected as especially important industrial cultural heritage site by the Trondheim Municipality.


The old paint was totally removed from the surfaces. Chemical were used to strip the organic thick layers. This process is gentle with the substrate- but also demands some fine work in tight areas with picking tools. In this project, the building owner emphasized the importance of using environmentally friendly products. The powerplant is situated in the Gaula river with a sustainable population of wild river salmon and trout.  All frost damaged bricks were removed and replaced. Frost damaged bedding mortars were scraped and repointed. For this work they used a weak lime-cement based bedding mortar. A two layer LC-based render was applied before a new coat of a damp diffusion open silicate paint was applied. For the stone-repair jobs on site, a standard premixed concrete was used.