Roof drainage systems should be designed and detailed by a suitably qualified trade or professional in accordance with the bca and the australian standards.
Box gutter regulations victoria.
Method for design of eaves gutter systems.
All professional plumbers are aware as of 1 1 16 the vba are enforcing as3500 3 2015.
And the provision of appropriate overflow devices.
Read about the new guttering standards introduced by the vba as of january 1 2016.
In my last article i discussed the emergence of the issue of provision for overflow in external eaves gutters or more specifically the lack of provision for overflow.
Allowable box gutter width slope and length required by the australian plumbing code as nzs 3500 3 2 box gutters allowable width slope and length to as nzs 3500 3 2018 stormwater drainage acceptable solutions.
In victoria the installation of box gutters is regulated plumbing work that must be carried out and certified by suitably registered licensed plumbers.
Roof coverings and associated flashings not installed in a good and workmanlike manner.
Particular reference should be made to the correct sizing of gutter.
Inappropriate box gutter size for the roof catchment area.
Peter coll provides a timely update regarding the provision for overflow and box gutter compliance.
Architects draftpersons builders and other practitioners responsible for designing a box gutter should work closely with the roof plumbers that will install the box gutter to ensure that the overall design and installation will be compliant with relevant regulations.
Quantity and placement of downpipes.
Insufficient number of downpipes appropriate for the roof catchment area.
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.
Saa snz hb114 1998 ci 3 6.
A recent audit performed by the victorian building authority found that many plumbers were installing eaves gutters with insufficient overflow capabilities.
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.
It isn t often that there are major changes to the construction industry s regulations so it s important to stay informed when there is a change.
The total flow is used to size the sump and overflow.
The side with the maximum flow is used to size the box gutter.
This has become a big issue in the past few months particularly in victoria and is going to be a new section in the upcoming.
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.
Plumbing regulations 2008 part 3 r 14.
