this weekend villa in japan resembles a pile of leaves, by kias

this weekend villa in japan resembles a pile of leaves, by kias

designed to accommodate the owners and their friends in the rich natural environment at a mountain retreat 150 kilometers away from tokyo, the ‘four leaves’ weekend villa built by kentaro ishida architects studio (kias) is located in the middle of a forest in karuizawa, nagano prefecture of japan. each function of the building faces its own desired orientation — living and dining spaces point at south-east for a brighter living environment, while the master bedroom and bathroom face west offering private scenery of the forest. these compartments are assembled into thee interconnected volumes, resulting in an unusual slope of the roofs resembling four leaves.

weekend villa in japan by kias resembles a pile of leaves designboom
south-east elevation view towards living and dining space
all photos by norihito yamauchi



in order to form variable cross-section suitable for each function, roofs are designed as curved surface like gently twisted leaves. the combination of concave and convex surfaces derives from the subtle flow of the high-ceiling rich space into introverted compact rooms. every roof has been designed as a ruled surface in which straight laminated veneer lumber joists are arranged continuously to form an organic geometry.

aerial view of four curved roofs



a series of wooden joists is exposed on the ceiling highlighting the dynamic spatial characters of each living space. the design process that responds to its environmental context has produced multiple organic roofs and established architecture as an aggregate of diverse living spaces. the appearance of the villa blends in harmoniously with the natural surroundings and is perfectly integrated to the local landscape.

east elevation


entrance courtyard with acer palmatum tree


weekend villa in japan by kias resembles a pile of leaves designboom
view towards convex roof over master bedroom and bathroom


the house is located in the middle of a forest


main living & dining space where its ceiling height varies from 2.5m to 6.0m


recreational space


weekend villa in japan by kias resembles a pile of leaves designboom
the panoramic window overviews the garden


the upper floor


the master bathroom


weekend villa in japan by kias resembles a pile of leaves designboom
the guest bedroom


project info:


name: four leaves villa

location: karuizawa, nagano, japan

program: weekend house

architect: kias (kentaro ishida architects studio)

structural engineer: building structure institute, tokyo (kazuyuki ohara, shuichi takahashi)

construction: sasazawa kensetsu

site area: 1,127 sqm

floor area: 225 sqm

completion: july 2018

photography: norihito yamauchi


designboom has received this project from our ‘DIY submissions‘ feature, where we welcome our readers to submit their own work for publication. see more project submissions from our readers here.


edited by: maria erman | designboom

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