Japanese language school / required English?

I thinking about apply to language school in Tokyo, but before I have questnion... good lvl in English is required/recommended/helpful to study Japanese in Japan or it really doesn't matter? It can be problem or… motivation to faster learn if your teachers, classmates, flatmates, co-workers dont’t understand you very well?
My English isn’t very bad but I can’t speak and write fluently. It’s enough to survive first months in Tokyo, before I improve my Japanese?

No,I don't think English is required. The school usually teaches through "direct method," meaning teaching Japanese through Japanese. Classes consist of people of different language backgrounds, so they cannot rely on English (or any other single language, other than Japanese) as a common means of communication.

For your daily living, if you speak a bit of Japanese, and bit of English, I am sure you will get along fine.

My answer is tottaly same as what AK-san said.

There are some teachers who use English when students don't understand what said in Japanese.
However, authentic teachers who were trained on a teacher's course should be able to explain in easier Japanese with another expressions.

Thanks for your help :)
This information was very useful.