I don't know about Wädi, but I know of a new very friendly one in Zürich that has just opened. I haven't been been inside - just looked in through the door - so I really can't say much about their walls but the people I know who have been there all say that it's really nice people running it with quite a laid-back atmosphere. It's on Seestrasse in Wollishofen, if you drive frome Wädenswil, it has the same entrance as the Kibag Cement place which is about 100m past the Rote Fabrik.... speaking of which, there is a "movement room" in the Rote Fabrik that can be used by anyone, which has a nice high wall with an over hang! You just need to called the "Sekretariat" to talk about booking it, I even have the number for you (just happen to be sitting in the office here) 044 4855858.
Have fun!