Box Gutter Overflow Requirements

All domestic box gutters must be a minimum of 200mm wide and 75mm deep.

Box gutter overflow requirements.

If draining to a sump with a vertical overflow somewhere along the box gutter use this calculator. For commercial projects the minimum allowable width is 300mm. Sides must be vertical. Rainhead overflow or specific box gutter overflow must be at least 30mm below the height of the back of the box gutter.

Have a minimum width of 300mm for commercial installations 200mm for domestic installations. Box gutters must be straight no bends. Have a sole width which is not reduced discharge at the downstream end without. The minimum width allowed for domestic projects is 200mm.

Trial box gutter width the minimum width allowed for domestic projects is 200mm. The width of the rainhead is to be at least equal to the width of the box gutter and the box gutter needs to be sealed to the rainhead. For commercial projects the minimum allowable width is 300mm. The vba has provided several options for plumbers to make an installation compliant.

This effectively states that all box gutters must allow for 30mm of freeboard which is from the overflow point eg. Use a 10mm spacer this creates a gap behind the gutter so water can overflow freely. Code box gutter requirements. The hydraulic capacity of the overflow device must be no less than the design flow for the associated box gutter outlet.

Overflow devices need to discharge to the atmosphere in such a way as.