Box Gutter Sump Regulations

This has become a big issue in the past 18 months particularly in victoria and is outlined in a new section in the current update to the ncc.

Box gutter sump regulations. If the box gutter has no overflow provisions this causes a waterfall over the sides of the box gutter typically running down the walls. Either a rainhead or sump. Rainheads are an essential design element for buildings where internal box or trough gutters are used. It sounds like you have an overflow situation.

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 outlet of the box gutter may be blocked by debris or the box gutter outlet simply cannot discharge the water fast enough. It acts as an external overflow point to reduce water surges into the stormwater system and aid the flow of water down. Box gutters plumbers must install a box gutter system in accordance with as nzs 3500 3 as nzs 3500 5 hb 114 and hb 39.

The total flow is used to size the sump and overflow. Architects draftpersons builders and other. As an alternative the top of the rainhead may be installed so that it is no higher than 50 per cent of the flow depth of the box gutter consistent with saa hb39 installation code for metal roof and wall cladding section 5 clause 5 7 3 and figure 5 7 3 to prevent internal flooding or damage to the building or contents see figure 2. Ensure that the overall design and installation will be compliant with relevant regulations.

The side with the maximum flow is used to size the box gutter. 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. A rainhead or sump is a container located between the gutter and downpipe that aids the flow of water away from the roof. Method for design of eaves gutter systems.

In victoria the installation of box gutters is regulated plumbing work that must be carried out and certified by suitably registered licensed plumbers. Vba openly disclose that they do not use the bca code as it believes their regulations are far more thorough and make construction in victoria of a better standard for the. Overflows in box gutter. This free online box gutter calculator will calculate the size of box gutters and sumps with a side overflow in accordance with the australian plumbing code as nzs 3500 3 2003 part 3 storm water drainage.