Must have a constant slope between 1 40 and 1 200.
Box gutter sizes australian standards.
Have a sole width which is not reduced discharge at the downstream end without.
Roof drainage systems should be designed and detailed by a suitably qualified trade or professional in accordance with the bca and the australian standards.
Down pipe must be vertical from sump not to the side minimum sump length is 400mm.
And the provision of appropriate overflow devices.
The minimum size of a sump is 400mm x 200mm minimum width of box gutter and 150mm deep.
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.
But houses with big steep roofs or those located in climates prone to heavy downpours may need wider gutters and extra downspouts to keep rainwater from overflowing.
Sides must be vertical.
Five inch k style gutters or 6 inch half rounds the most common residential sizes are able to handle the rainfall on most houses in most parts of the country.
The building code.
In addition to referring to australian standards as nzs 3500 3 2003 and as nzs 3500 5 2000 the bca also contains requirements for the disposal of surface water in volume one in performance requirements fp1 2 and fp 1 3 and in volume two in part 3 5 2 namely performance requirement p2 2 1 and clauses 3 5 2 1 and 3 5 2 4.
Particular reference should be made to the correct sizing of gutter.
A box gutter must be installed with a fall not less than 1 100 and be designed in accordance with the joint australian and new zealand standard as nzs 3500 3 or section 5 of as nzs 3500 5.
Sizes the depth shown of the box gutter is the depth at the upstream end.
The building code of australia bca changes each year so it can take time to keep up to date with the requirements that apply to new homes and renovations.
This free online box gutter calculator will size box gutters and rain water heads in accordance with the australian plumbing code as nzs 3500 3 2003 part 3 storm water drainage.
Box gutters must be straight no bends.
Have a minimum depth of 75mm at the high end.
To use the gdo calculator enter information about the location roof design and types of overflow measures.
Have a minimum width of 300mm for commercial installations 200mm for domestic installations.
Sumps are to be appropriately sized in accordance with as nzs 3500 3 with a minimum length of 400 mm and when fitted with a high capacity overflow device with a depth of not less than 150 mm when either one or two box gutters enter the sump.
But can be used for anywhere in the world provided you know the rainfall intensity requirements for your local area.
