How Many Downpipes For Roof Area Australia

Figure 1 an example of a roof with a total plan area of 98 m.

How many downpipes for roof area australia.

Select 100 x 50 rectangular downpipe. Using the aggregate area of these simple shapes can yield a more accurate roof area to be used with the roofing material calculator. How many downpipes do you need. Calculators for designing eaves gutters box gutters downpipes pipes and open channels etc to australian standards.

And the provision of appropriate overflow devices. To use the gdo calculator enter information about the location roof design and types of overflow measures. 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. From figure 3 5 a in as nzs 3500 3 the maximum catchment per downpipe is 47m 2.

Usually the size for the largest collection area on the roof is used to size downpipes throughout. To calculate the minimum number of downpipes divide the roof catchment area by the allowable maximum catchment per downpipe. And downpipe outlets channel water from the gutter to the downpipe. Min number of downpipes roof catchment area.

The answers for downpipe size are in mm. Complete your spouting project with a range of downpipe accessories. The most common roofing materials used in the united states include shingles membrane roofing and ceramic tile all of which have different life spans. The number of downpipes you need will depend on the size of your roof and your chosen style of guttering.

Shingle roofs typically have a life span of 15 30 years. Design of eaves gutters box gutters downpipes to the australian national plumbing code as nzs 3500 3. The 6 in 12 pitch factor 1 1 multiplied by 1 000 yields an effective area of 1 100 square feet. 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.

Sizing downpipes downpipes are sized for the areas that discharge into them. Downpipe straps attach the downpipe to the wall downpipe shoes 135 and elbows 90 help water flow to a specific area. Roof drainage systems should be designed and detailed by a suitably qualified trade or professional in accordance with the bca and the australian standards. 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. Using clause e1 table 5 see figure 2 at a roof pitch of 45 for this example. This is because larger roofs require bigger volumes of water to be diverted away from them during periods of rainfall. Quantity and placement of downpipes.

The program will calculate the most suitable circular and rectangular downpipe sizes. Particular reference should be made to the correct sizing of gutter.