The 20-year-old glamour model upset the ex-Hills star when she began to undress in front of her, causing Heidi to flee to the bedroom before branding her behaviour "super inappropriate" to husband Spencer Pratt and former Heartbeat actress Tricia Penrose.
Heidi added: "I don't wanna be around it, not around me and my husband."
Earlier in the week, a naked Banghard attempted to protect her modesty after forgetting her towel and emerging fully nude in the lounge to retrieve it.
Meanwhile, Spencer took a more laid-back approach to the naked drama unfolding in the house and applied a face mask to relax instead.
He added: "If it was a clear shower, maybe it's a big deal. I'm sure other people are showering naked."
Banghard, Heidi and Spencer, Rylan Clark and Claire Richards all face eviction tonight (Wednesday, January 16).
Celebrity Big Brother continues every night at 9pm on Channel 5.
See other celebrities stripping off in the Big Brother house here.