Box Gutter Overflow Design

Eaves gutters form the outer perimeter of the roof and their shape allows excess water in high rainfall events to safely overflow over the outside lip of the gutter.

Box gutter overflow design.

This effectively states that all box gutters must allow for 30mm of freeboard which is from the overflow point eg. Drill rivet holes for the gutter splash guard. All domestic box gutters must be a minimum of 200mm wide and 75mm deep. Holes through the splash guard and the gutter.

Roofs may be constructed with or without gutters. Overflow box gutters must have independent overflow provision discharging to the atmosphere. Layout box gutters must. A good box gutter design will have falls along its length together with sumps to collect water before it is fed into large downpipes.

There will also be an overflow facility on the side or the end. Failing to install appropriately designed box gutters and correctly sized and positioned overflow devices can lead to serious damage to buildings and contents especially in shed and flat house roof designs often resulting in hefty insurance claims which are a total burden. There are two categories of gutters. Overflow devices need to discharge to the atmosphere in such a way as to prevent damage to buildings and property.

Rainhead overflow or specific box gutter overflow must be at least 30mm below the height of the back of the box gutter. You can find these precut gutter splash guards about 3 in brown and white aluminum at a home center but you could easily make your own out of aluminum or sheet metal and spray paint them to match your gutters. 2015 3 7 4 layout. Eaves and box gutters.

The hydraulic capacity of the overflow device must be no less than the design flow for the associated box gutter outlet. A wider overflow needs less depth of overflow hence the box gutter depth will also be reduced. Support the entire weight of the gutter and sumps when full of water as well as a trafficable load at any point in the gutter and sumps. Box gutters sit within the façade or structure of the building.

Sump with a side overflow device. Outlets box gutter outlets must discharge through either a rainhead or sump. However a wider overflow may increase the length of the sump.