Japanese houses are described as a rabbit hutch, because they are so small.
The landmass of Japan itself is 30% bigger than Britain, but 70% of our land is steep mountainous terrain, which is unsuitable to live on, or to cultivate.
Having almost twice as much population of Britain, Japanese people have to share the limited space each other, hence our houses are small.

Japan is one of the most notorious country where big earthquake occurs often, my husband experienced it first time in his life in Yokohama. He said that was very shocking occurrence for him, but Japanese workers didn't bother at all! they are so used to that. The small earthquakes are everyday event in some part of Japan.

Japanese houses are built by mainly woods, not bricks or stones. The reason for this is to cope with long hot humid summer, and prepare for next earthquake. Our ancestors learnt a lesson from their experience, wood houses are easy to rebuild once they are demolished by earthquake.
In Britain, it is very rare occasion to build a order-made house.
People normally buy a house which already exist, so we have to look around many properties before finding one, to suit our needs.
Modifying properties also needs permission. I was surprised before starting extention or even making new window, we have to ask neighbors if they don't mind to go ahead the plan.
In Japan, as long as the plan complies building regulation, it's OK to do so.

It sounds nice isn't it? But realty is, we end up with ugly irregular house complex which is worse than a bee hive.
Many house owner want a house as big as possible, so some houses are standing close next to each other, it makes me wounder how the builder did it?
If you go to the country side, it is a different story. You will see large well constructed old houses which were built hundreds years ago, still being kept in beautiful condition. They are real charm and pride of Japan.

Many Japanese houses are rebuilt every 40-50 years. Because of woods are not strong material, especially modern mass produced one is not in a good quality, become distorted or rotten easily.
Therefore, the house itself loses its value every year, as same as a car.

When I went to Japan this year, I was surprised to see the price of properties. They are low coster than Britain! ( Kanazawa and surrounding area, not Tokyo, of course )
Another reason we Japanese living in a small properties is, I believe, we are generally smaller than British.
Look around you including yourself, do you think British need bigger space than Japanese, don't they?
You know, the Sumo wrestlers living in a large properties.

( I'm just kidding )