Offsets are available to fit either a 450mm or 600mm eaves overhang.
How many downpipes for roof area australia.
A house in chicago has a roof whose actual drainage area is 1 000 square feet.
From figure 3 5 a in as nzs 3500 3 the maximum catchment per downpipe is 47m 2.
Min number of downpipes roof catchment area.
The number of downpipes you need will depend on the size of your roof and your chosen style of guttering.
To calculate the minimum number of downpipes divide the roof catchment area by the allowable maximum catchment per downpipe.
How many downpipes do you need.
63 mm diameter downpipes.
Complete your spouting project with a range of downpipe accessories.
Calculators for designing eaves gutters box gutters downpipes pipes and open channels etc to australian standards.
The answers for downpipe size are in mm.
Downpipe straps attach the downpipe to the wall downpipe shoes 135 and elbows 90 help water flow to a specific area.
Using the aggregate area of these simple shapes can yield a more accurate roof area to be used with the roofing material calculator.
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.
Figure 1 an example of a roof with a total plan area of 98 m.
Design of eaves gutters box gutters downpipes to the australian national plumbing code as nzs 3500 3.
The program will calculate the most suitable circular and rectangular downpipe sizes.
Divide the main roof into catchments of this size and any left over area can be entered again to find a down pipe size for this smaller area.
Shingle roofs typically have a life span of 15 30 years.
Usually the size for the largest collection area on the roof is used to size downpipes throughout.
And the provision of appropriate overflow devices.
Select 100 x 50 rectangular downpipe.
Determine minimum number of downpipes.
Multiplying that number by the local maximum rainfall intensity 6 8 inches per hour yields an adjusted square footage of 7 480 square feet.
The 6 in 12 pitch factor 1 1 multiplied by 1 000 yields an effective area of 1 100 square feet.
To use the gdo calculator enter information about the location roof design and types of overflow measures.
Roof drainage systems should be designed and detailed by a suitably qualified trade or professional in accordance with the bca and the australian standards.
Quantity and placement of downpipes.
Particular reference should be made to the correct sizing of gutter.
Using clause e1 table 5 see figure 2 at a roof pitch of 45 for this example.
And downpipe outlets channel water from the gutter to the downpipe.
