“Morutoru” Tile Renovation Technology
“Morutoru” Tile Renovation Technology KITAKARO Sapporo Honkan
Keeping History, Preserving Beauty

When working with buildings of historical importance, it is better to restore wall tiles to their original condition rather than replace them. To do this, they have to be detached. The old mortar on their hidden side has to be removed and new mortar applied—all without damage to the tile itself. This is no small feat.

Takenaka’s “Morutoru” is a tile technology that makes this kind of restoration possible. It was used for the first time to renovate the KITAKARO Sapporo Honkan Building, originally the Hokkaido Prefectural Library built in 1926 and now home to a café and confectionary shop.

Restoring the building allowed its historical atmosphere to shine forth, enhancing the viability of the commercial outlets that call it home on the street level.

“Morutoru” uses a special chemical solution to dissolves the original mortar cleanly without harming the tile Itself, or affecting its color and texture.

Takenaka intends to use this technology proactively to preserve and restore much-loved historical buildings.

Technological Outline

Three processes:

  1. Careful removal of tiles
  2. Dissolving original mortar with chemical solution
  3. Tiling

Tiles to be reused are carefully removed, avoiding damage. Next, they are soaked in a chemical solution for 2 to 4 weeks. The chemical solution dissolves the original mortar but does not affect the tiles themselves. Finally, the clean tiles are replaced using appropriate materiel and methods chosen according to the structure of the building and usage.

“Morutoru” : tile restoration technology

“Morutoru” : tile restoration technology

Tile soaking in chemical solution

Tile soaking in chemical solution

Cleaned with “Morutoru”

Cleaned with “Morutoru”


2016 3Rs (Reduce, Reuse, and Recycle) Promotion Merit Awards: MLIT(Minister of Land, Infrastructure and Transport) Minister’s Prize
Resource Recycling Technology and System Commendation : Honorable Mention
Construction Recycling Technology Exhibition: Award of Excellence
KITAKARO Sapporo Honkan
2017 BELCA Prize: Best Reform Division
JAAF(Japan Association of Architectural Firms) Awards: Award of Excellence
2016 Good Design Award
First Prize: Hokkaido Red Brick Architecture Award

Project Outline

Location Chuo-ku, Sapporo-shi ,Hokkaido
Design and Construction Takenaka Corporation
Basic Design Tadao Ando Architect & Associates
Completion 2016
Area Site Area 885.8㎡ Building Area 537.32㎡ Total Floor Area 11351.38㎡
Number of Floors 4 stories above ground with 1 basement floor