Nobody is obliged to look

Overseas buyers often assume that somebody inspects the building as a matter of course, because in their own market somebody does. In Japan that step is optional.

Since 2018, a broker handling a secondhand house has had three duties attached to the formal building condition survey. The mediation agreement must state whether the broker can arrange for one to be carried out. If a survey has been done, its findings and the state of the building's records must be explained before contract. And at contract, matters the parties have jointly confirmed about the structure must be recorded in writing.

Read those again and notice what is missing. All three concern disclosure and arrangement. None of them requires that the building is actually inspected. From April 2024 a broker declining to arrange one has had to give a reason, which is an improvement, and it still stops well short of an inspection happening.

In practice a minority of transactions include one. Figures vary with how they are counted: one ministry survey of buyers put it at around a third, while estimates based on surveyors' own activity have been far lower.

There is a further point that surprises people, and it was added to the standard mediation agreement in 2024 precisely because it was causing disputes. A building condition survey does not determine whether defects exist. It is a visual examination against a defined method, by an architect holding the relevant qualification, of the structural elements and the parts that keep rain out. It is genuinely worth having. It is not a certificate that the house is sound.

So if nobody goes under the floor, nobody goes under the floor, and the sale completes regardless. The responsibility for establishing the condition of the building sits with the buyer, which is the theme running through everything you must verify yourself before buying.

Why these two places and not others

Rooms can be presented. Wallpaper is re-hung, flooring is replaced, and a professional clean changes a house completely. None of that is dishonest, and all of it works.

The underfloor space and the roof space are never presented, because nobody has ever thought it worth the money. How the house has actually been treated is still sitting in both of them, untouched.

Under the floor

Most timber-framed Japanese houses have a crawl space a person can get into. Access hatches are usually in the kitchen or utility room floor, or inside a cupboard.

Appearance is not enough here. Timber well into decay can look entirely normal on the surface. What identifies it is whether it gives when pressed, whether it sounds dull when tapped, and what it smells like. A photograph of the surface misses that stage completely.

In the roof space

Access is typically through a ceiling hatch in a cupboard or a hallway.

The roof space keeps the most honest record of leaks. A ceiling below can be replaced, and the marks above it remain. It is entirely normal to find several old stains in a roof space belonging to a house whose owner says there have been no leaks. That is usually not a lie. It is something a previous owner dealt with, and the current one never knew about.

The row about wings and grit deserves attention on any older house. Japanese termite treatment is built around species that come up from the soil, and the species that arrives by air lives upstairs. That distinction, and the warranty exclusion that follows from it, is covered in the termite your five-year warranty does not cover.

Sometimes you physically cannot look

Access is not always possible, and that in itself is information worth having.

• No hatch. Not unusual in older houses. Lifting a tatami mat sometimes provides a way in.
• Insufficient height. The space is too shallow for a person to move through.
• Compartmented foundations. The underfloor is divided, so one hatch does not reach the whole of it.
• Belongings in the way. A cupboard packed to the ceiling, with the hatch behind it.

When this happens, what anyone can honestly tell you is limited.

"We checked and found no problems" and "we could not check" are entirely different statements. They are also easy to blur, in a report, in a second language, when everyone would prefer the first. Whenever you receive an account of a property's condition, establish which of the two you are being given, area by area.

From practice

Across years at a housing manufacturer I stood on a great many demolition sites, taking down one company's house to build another's. When demolition starts, everything that was concealed comes out at once.

Rat droppings pouring from a ceiling void. An underfloor space that had become a pond. Not once or twice.

From the outside, every one of those houses had looked completely ordinary.

One more thing from those years. What a photograph cannot carry, the site delivers through smell. The air as an underfloor hatch comes open, the back of a cupboard, the first few seconds after walking through the front door. No camera records it, and for anyone with experience it is among the fastest reads available.

Photographs have requirements too

If you are buying from abroad, this information reaches you as photographs and video. A single image captioned "underfloor" is not something a decision can rest on.

Documentation that is actually usable has five properties.

• Located. Which room it is beneath, which side of the house.
• Wide and close. Without the wide shot, nobody can place the close-up.
• Scaled. A rule or a tool in frame, so crack width and stain size mean something.
• Dated. The basis for comparison on the next visit.
• Inclusive of the normal. Photograph the sound areas as well as the problems.

The last one matters more than it sounds. A set of photographs showing only the defects gives you no sense of the house. Six bad photographs of a fundamentally sound building and six bad photographs of a failing one look identical.

And whatever care is taken, one thing never appears: the smell. Damp, mould, animal, drainage. Only the person standing there knows. Which is why a report should say in words what was sensed on site, alongside what was seen.

What is found becomes a number

None of this work becomes cheaper for having been discovered later. The money is the same either way. What changes is whether it was in the budget. On inexpensive property that distinction is the whole difference between a good purchase and a bad one, as set out in what a cheap Japanese house actually costs.

Five questions to ask

1. Are there access hatches to the underfloor and the roof space, and where are they?
2. Has anyone actually been into the underfloor space, and when?
3. Is there any history of leaks or termite damage, and of repairs to either?
4. Has a building condition survey been carried out?
5. If not, may we arrange one at our own cost?

Do not hesitate over the fifth. A buyer paying for a survey is an ordinary arrangement in Japan, not an imposition. Tens of thousands of yen, on a decision worth millions, that can change the decision.