Seperation wall question

[Marc M]

Jerry, I just want to confim that plastic laundry utility boxes (used to house drain+water) are NOT allowed in the seperation wall between garage and house.
And, how do plastic electrical boxes or coverplates play a role in this wall?
R302.4.2 Membrane penetrations.

[Jerry Peck - Codeman]

Presuming that this is on the garage side, this is not good, but how 'not good' depends on the answer to the next question.

Question: Does California require actual "fire walls" between a garage and a house, or only separation? Or maybe even something in between the two?

A true fire wall is fire rated from both sides (one example may be 5/8 inch Type X on both sides of the wall, taped, opening protectives, etc. - on both sides of the wall).

Some areas only require the garage/house separation wall to be fire resistant (not truly fire rated) on the garage side (Type X on the garage side only, 1/2" gypsum on the other side, no opening protectives either side, but maybe Type X covering the washer box in your photo as a five sided box around the back side of the washer box).

Other areas, most areas now, do not require Type X on either side of the wall, and thus no opening protectives, however, those areas would require 1/2" gypsum or equivalent on the garage side, which means that plastic box would need a five sided box made from 1/2" gypsum enclosing that plastic box.