I'd like to check the type of road.

We can confirm in authorized route map of road ledger figure information "Yokohama no Michi" in "administrative map information" of Motoichi homepage to check whether road is public road. In addition, we can read authorized route map in [city hall the second floor "Yokohama Building Information Center"] or [Public Works Office of each ward].
※　Inquiries: 22nd floor of 10 City Hall, 6-50 Honcho, Naka-ku [Road and Highway Bureau Road Investigation Division] (TEL045-671-2774)
In addition, please refer to [Housing and Architecture Bureau Building Guidance Division] (city hall the 25th floor TEL045-671-4531) about road classification in Building Standard Act.

<Related Homepage>
Road ledger map information "Yokohama no Michi"
http://wwwm.city.yokohama.lg.jp/ (outside site)

Answer:
Road Investigation Division
Telephone: 045-671-2774 FAX: 045-550-4954