Box Gutter Overflow Design

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.

Box gutter overflow design.

This is very important so that water will overflow externally to the building rather than flood into the roof cavity. A good box gutter design will have falls along its length together with sumps to collect water before it is fed into large downpipes. Holes through the splash guard and the gutter. A rainhead or sump is a container located between the gutter and downpipe that aids the flow of water away from the roof.

To use the gdo calculator enter information about the location roof design and types of overflow measures. A box gutter is defined as a graded channel generally of a rectangular shape for the conveyance of rainwater within the building footprint including adjacent to a wall or parapet. The hydraulic capacity of an overflow device shall be not less than the design flow for the associated gutter outlet. Overflow devices need to discharge to the atmosphere in such a way as to prevent damage to buildings and property.

The box gutter depth and the sump length are influenced by the size of the overflow. Making the box gutter wider will also reduce the box gutter depth. The gutters downpipes and overflow gdo calculator assists in developing a better understanding of the ncc volume two part 3 5 3 gutters and downpipes acceptable construction practice acp provisions. Overflow devices shall discharge to the atmosphere.

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 will also be an overflow facility on the side or the end. Drill rivet holes for the gutter splash guard. Sump with a side overflow device.

However a wider overflow may increase the length of the sump. Rainheads are an essential design element for buildings where internal box or trough gutters are used.