Culvert Guesthouse

Culvert Guesthouse
© Takumi Ota

CULVERT GUESTHOUSE

Nendo

ARCHITECTS
Nendo

FILMING
Takahisa Araki, Masaya Yoshimura

COLLABORATORS
Noritaka Ishibayashi, Ryota Maruyama, Daisuke Maeda

FILMING AND EDITING
Toru Shiomi

PHOTOGRAPHS
Takumi Ota, Daici Ano

YEAR
2022

LOCATION
Japan

CATEGORY
Hospitality Architecture, Gallery

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota

Text description provided by architect.

A storage facility for archiving furniture, products, and artwork in Miyota-machi, Nagano Prefecture, with a guesthouse attached.

Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota

Located in a quiet and nature-rich environment where streams weave through a thick forest of red pine, the tunnel-like architecture took shape through a combination of precast and prestressed construction methods.

For precast construction, common parts are molded in a factory and assembled on site.

Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota

An example of its applications in infrastructure projects is the box culvert (box-shaped concrete structures), used to store waterways, pathways, power lines, and communication lines buried underground.

However, since the method itself does not provide a leak-free composition nor does it allow for stacking, both necessary for this architecture, prestressing was also used to connect the parts together.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota

The prestressing method is a technique used in civil engineering structures such as bridges, in which the parts are aligned and then tightened with wires to connect them.

This results in a seamless and smooth surface finish, obtaining a tight seal, and durability.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano

The common square-shaped parts weigh approximately 12 tons each, and a total of 63 of these parts were used.

The size of the parts was derived from the loading size of the delivery truck and the weight that could be lifted by a crane.

Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota

The 45-degree reinforcement at the entry corner, which is also found in general box culverts, serves as a brace and enhances earthquake resistance.

By connecting these parts, a slender, tunnel-shaped space with an internal dimension of approximately 2 x 2.3 m was created.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota

Fourteen wires were used to connect each “tunnel” and care was taken to apply uniform tension to each wire at all times.

The work involved gradually tightening the wires over time until a tension of 46 tons was finally applied to each.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota

The building is composed of four stacked “tunnels” covered with a roof in the center.

In addition to a long, narrow storage room with a depth of approximately 40 meters, there are two smaller storage rooms, but it is envisioned that more will be added to the site in the future as the collection grows.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano

The kitchen, bathroom, toilet, and other water facilities are concentrated on the first floor, and a compact bedroom and a study are located on the second floor.

The windows were made without metal frames as much as possible, and high-transparency glass measuring up to 10 meters in length was fixed into the grooves in the same manner as shoji screens.

Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano

The gravel and plantings used in the exterior were also arranged in the interior to draw the outside environment into the interior.

To make it easier to walk on, the gravel was partially hardened with resin.

Instead of just pouring resin over the gravel, which is usually the case, the resin was applied to the base first and then gravel was laid on it so that the surface wouldn’t become glossy.

Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano

In addition, the door handles would have looked abrupt if installed as-is, so an original handle was designed, which hides in the small gap between the door and the wall.

The bathtub is carved into the floor, such that the water surface aligns with the floor, creating the appearance that the tunnel shape is continuous.

Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota

The resulting space is less architectural, but rather a project that combines civil engineering concepts with product design details.




Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano


Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota


Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Daici Ano
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota
Culvert Guesthouse
© Takumi Ota


Culvert Guesthouse
Plan - 1st Floor
Culvert Guesthouse
Plan - 2nd floor


Culvert Guesthouse
Section
Culvert Guesthouse
Plan - Site