Making the box gutter wider will also reduce the box gutter depth.
Box gutter sump design.
To avoid problems plumbers need to calculate the hydraulic capacity of a box gutter and when designing overflow devices consider whether the discharge of the box gutter is to.
A a rainhead b a sump with a side overflow device.
Layout box gutters must.
However a wider overflow may increase the length of the sump.
Box gutter procedure on roof of new 2 story house with flat roof top.
A good box gutter design will have falls along its length together with sumps to collect water before it is fed into large downpipes.
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.
To do this we need 3 things what is the biggest storm we should design for.
Box gutter design to as 3500 3 2015.
Overflow box gutters must have independent overflow provision discharging to the atmosphere.
Design a box gutter to an internal sump with a vertical overflow.
At this stage plan the connection to the downpipe.
Outlets box gutter outlets must discharge through either a rainhead or sump.
If draining to a sump with a side overflow somewhere along the box gutter use this calculator.
Refer to hints for box gutter design marking and cutting the sump spigot mark cut sump hole dress the cut out to neatly fit to the sump decide on the position of the spigot mark and cut the hole.
A rainhead or sump is a container located between the gutter and downpipe that aids the flow of water away from the roof.
Design a box gutter to an internal sump with a side overflow.
Each box gutter run must discharge independently to ether a sump or directly out of the building without changing the size of the gutter or changing direction.
The water is drained via downpipe nozzles or via a sumps downpipes built into it.
Or c a sump with a high capacity overflow device.
The box gutter depth and the sump length are influenced by the size of the overflow.
Typically a box gutter is trapped between two roofs that feed rainwater into it.
With building design being so restrictive on space these days this is the area where designers must think about how the roofing contractor will make the box gutter comply.
Method used the method used is based on the flow chart fig 3 1 as nzs 3500 3 2003 downpipe and sump depth from fig i4 with minimum sump depth 150mm.
Establish the sump location this should be the lowest point in the box gutter.