Oba Family Residence Main House

A late Edo farmhouse under a decorated thatch roof

Oba Family Residence Main House is a single-storey thatched farmhouse of the closing decades of the Edo period, built at Saku in Ishioka City, Ibaraki Prefecture, and placed on the national register as a Registered Tangible Cultural Property in 2005.

No building date survives, so the record gives a bracket rather than a year: somewhere between 1830 and 1867. The house sits in the middle of its plot, facing south, on the flat farmland of the Yasato basin under the northern slopes of the Tsukuba range. A grape trellis screens the approach. Pass under it and the outbuildings appear on the right, a garage and a storehouse, a manure shed and a barn, while a study wing and a second storehouse stand across the front garden and a retirement house sits further back. Of all of this, only the main house carries the registration.

The plan runs 8 Ken along the front and 4 ken and a half deep, giving a building area of 157 square meters. That is a large farmhouse by any standard. The roof is hipped in the Yosemune-zukuri manner and covered in Kayabuki thatch, and the entrance is on the long side, the arrangement called Hirairi.

The framing tells its age. Room divisions, the form of the Tokonoma alcove and, above all, the way the sashigamoi are used all follow older practice. A sashigamoi is a deep horizontal timber that serves at once as the head of a sliding-door opening and as a structural beam. Later carpenters split the two functions apart. Here they are still one member, and the reading of that detail is much of why the building was registered.

Why Oba Family Residence Main House is on the register

The formal grounds are the standard ones for the Registered Tangible Cultural Property system: this is a building that contributes to the historic character of the national landscape. Ishioka City puts it more plainly. What matters here is the roof, and specifically the fact that the roof is a demonstration piece of a regional thatching tradition known as the Tsukuba school.

Thatch is normally treated as a surface. In this tradition it is treated as a place to work. The eaves edge of Oba Family Residence Main House is built up in four courses of the bundled rods called tōshimono, so that the cut face of the thatch reads as four distinct bands rather than one thick lip. The ridge is bound in bamboo screening. Into that binding is worked a shaped crest of palm fibre, known locally either as the topknot or as the daimyō ridge, depending on who is describing it.

The two ends of the roof carry pictures. On the west, in the trimmed face of thatch that thatchers call takodome, the character for long life is cut into the surface. On the east, the sawn ends of bamboo are set into the thatch to compose pine, bamboo and plum, the three plants that Japanese decoration pairs with endurance through winter. None of this keeps the rain out any better. It is display, executed in a material that has to be renewed every few decades, which means every renewal is a decision to do the work again.

Registration in 2005 covered the main house alone. The study wing, the storehouses and the retirement house on the same plot are not on the register, though they are part of what makes the setting legible. The house is still a working farmstead rather than a museum, and the register was designed for exactly that: it asks the owner to notify the state before major alteration, and otherwise leaves the building in use.

What to look for at Oba Family Residence Main House

Everything worth seeing at Oba Family Residence Main House is above eye level.

Begin with the eaves edge, the horizontal band where the thatch has been cut off clean. Look for the horizontal lines running through it. There are four, one for each course of tōshimono, and they are not accidental; getting them parallel across an eight-ken frontage is the whole difficulty of the job. Follow the band round to the corner and watch how it turns without the lines breaking.

Then raise your eyes to the ridge. The bamboo wrapping is visible as a series of pale ribs against the darker thatch. Sitting on it is the fibre crest. Whether you read it as a topknot or as something more courtly depends on the angle you stand at, which may be why the two names have both stuck.

Now walk far enough west to see the end of the roof square on. The character cut into the thatch there means long life and appears constantly on Japanese gifts and celebrations. It is carved, in effect, out of grass. Then walk to the east end for the second panel, where cut bamboo ends have been pushed into the thatch to make pine, bamboo and plum. Bamboo used to depict bamboo is the kind of joke that thatchers have always enjoyed.

Two more things, lower down. The eaves are pushed out beyond the wall on two sides by segai brackets, short arms that carry the roof edge further than the frame alone would allow, which is why the shadow under the eaves is so deep. And in front of it all is the grape trellis. Fruit growing is the mainstay of this part of Ishioka, and the trellis is not decoration; it frames the house because it is what the family farms.

The old cedar of Saku stands close by, a landmark for anyone navigating these lanes by eye rather than by map.

Visiting Oba Family Residence Main House

Oba Family Residence Main House is a private home, occupied and farmed, and it is not open to the public. There is no admission, no opening time and no interior access. The roof, which is the reason to come, can be seen from the public lane outside the grape trellis. Do not pass under the trellis or enter the yard.

Photography from the lane is not restricted. Use a moderate telephoto if you have one, since the decorated ends of the roof sit some distance back from the boundary, and keep people and vehicles belonging to the household out of the frame.

Saku lies in the Yasato basin about 10 km northwest of Ishioka Station on the JR Joban Line, roughly 25 minutes by taxi or car. Kanto Railway buses on the Hayashi Line link Ishioka Station with Kakioka across the basin, and a sightseeing route also runs from the station into the Yasato area, but services are infrequent and none is timed for a single building, so a car is the practical way to reach Oba Family Residence Main House. There is no visitor parking; if you drive, find a safe place clear of the lane and do not block field accesses.

Season matters more here than at a tiled building. New thatch is a warm gold and weathers over years to grey-brown, so the roof looks like a different object depending on how long it has been since it was last laid. Winter, with the vines bare and the trellis reduced to wire and posts, gives the clearest view through to the house. In late summer the leaf canopy closes and Oba Family Residence Main House is largely hidden from the lane.