Pipes & Fittings - Supadiverta - syphonic rainwater diverter

Australian made and owned
Divert and capture rainwater, divert leaves and debris, extract debris
Divert and capture rain water
Divert capture rainwater, flush and sediment extraction
Distrubte, divert and capture rain water
Supadiverta is trade marked
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Pipes and fittings - so many choices.
.......... one more reason Supadiverta is such a great choice!

The Supadiverta is designed to fit 100mm x 50mm downpipes.
If you do not have this 100mm x 50mm downpipe, various adaptors are available.
The most common alternative is the 90mm round downpipe - the adaptors are available here.

A 95mm x 45mm x 90mm downpipe adaptor fits into the top inlet and fits snugly to the bottom stormwater outlet.

A 100mm x 50mm x 90mm downpipe adapter requires a 100mm x 50mm PVC sleeve to fit to the top inlet but it is the neatest fit.

    Use poly pipe, PVC pressure pipe, PVC DWV pipe or a combination of all three!
    • References to 1st, 2nd and 3rd priority outlets refers to the outlet’s order of use, the lowest outlet having 1st priority use and the tallest outlet having 3rd priority use.
    • The middle outlet is usually reserved for first flush and continuous sediment diversion.
    • The term faucet refers to a fitting with a female thread, usually at one end only.
    • POLY PIPE AND FITTINGS are cheap, easy to alter and mostly used for gardens.
    • An inline tap is fitted to the horizontal pipe to stop diversion when not required.
    • Using horizontal 25mm poly pipe at ground level reduces friction loss.
    • A ground level 25mm poly pipe fed by two 19mm vertical drops will often supply a nearby tank from a small roof area.
    • 25mm poly pipe vertical drops are slow to prime, only use 19mm poly pipe.
    • PVC PRESSURE PIPES AND FITTINGS have low friction losses and are AS 4020 compliant for use with potable water.
    • PVC pressure pipe sizes are nominal, their internal diameters are larger.
    • 20mm PVC pressure pipe (internal diameter is 23.7mm) vertical drops have high flow rates.
    • 25mm Class 12 PVC pressure pipe (internal diameter is 29.8mm) can be fitted with a purger and used for vertical drops in high intensity rainfall areas to generate higher flow rates.
    • The three syphonic outlets can be plumbed to one large vertical drop for very high flow rates.
    • Class 9 PVC pipe has a larger internal diameter and is cheaper than Class 12 pipe.
    • PVC DWV (Drain Waste Vent) PIPES AND FITTINGS are cheaper than large pressure pipes and can be used for greater volume diversion or when diverting long distances.
    • Note that DWV pipe internal diameters are truer to size than the pressure pipe nominal sizes.
    • The Supadiverta system is a low pressure application, reducing nipples and faucet sockets can be used to connect PVC pressure pipe to PVC DWV pipe.
    • AS/NZS 2032 Installation of PVC pipe systems specifies that PVC pressure pipes installed in direct sunlight must be either painted with light coloured water-based paints or otherwise protected.
    Selecting the best pipe size depends on the intended use, the roof area harvested and the regions rainfall intensity.
    This FAQ explains how to make the correct choice.

    PVC VALVE SOCKETS A 20mm x 3/4" BSP male threaded valve socket screws into a SUPADIVERTA 3/4" BSP female threaded outlet and a (nominal) 20mm PVC class 12 pipe slips into the valve socket’s tapered end. The use of PVC solvent cement is strongly discouraged for this connection. SUPADIVERTA outlets and PVC valve sockets are tapered, Teflon tape must not be used.
    The vertical drops connect to either individual horizontal  pipes or to a shared pipe.

    If using 19mm poly pipe drops, the poly fitting used is a 19mm x 3/4" BSP male threaded poly director.
    PHOTO 1: Two 20mm PVC vertical drops divert to a 25mm x 20mm reducing elbow and a 25mm x 20mm reducing tee. The elbow and tee are joined by a 25mm PVC pipe (not shown) cut to size.
    Supadiverta is designed to use 20mm vertical drops but larger 25mm class 12 PVC vertical drops can be used with 25mm x ¾” BSP male threaded valve sockets provided that a 25mm air purger is fitted into the top of the 25mm pipe. If a 25mm PVC vertical drop is not fitted with the purger, the drop can take a long time to prime which delays transition to full flow.

    This combination is used for larger roof areas or in high intensity rainfall areas.

    Do not use the greater volume 25mm class 9 pressure pipe as a vertical drop.

    PHOTO 2: A larger 25mm vertical drop is shown diverting to a 25mm plain elbow.
    Inside supadiverta

    PHOTO 3: 25mm and 20mm PVC drops are shown diverting to 40mm fittings. A 40mm x 25mm bush adapts the 25mm drop to the 40mm elbow.

    (Two tees are used when two Supadivertas connect to a shared horizontal pipe).

    Two 45 degree elbows used to raise or lower a pipe’s height have less turbulence and friction loss than two 90 degree elbows.
    A plain tee can be used to make an effective sediment trap in a horizontal pipe. See photos 13 & 14.
    A reducing tee can be fitted to a horizontal pipe to fit a connection that attaches to drip hoses for garden watering. See photos 8, 9 and 10.
    Bushes fit into PVC fittings, allowing different pipe sizes to connect.

    PHOTO 4: Tees, elbows and bushes come in a range of sizes. Tees and elbows are also available as faucet fittings.
    Joins two PVC pipes. Reducing joiners are also available for joining different size pipes.

    Joins a PVC pipe to a male threaded fitting.

    Fits into PVC fitting and connects to a male threaded fitting.

    Very useful and also available in some reducing and increasing sizes.
    19mm directors and 19mm poly pipe can be used as vertical drops, mainly for garden applications and are often used with PVC faucet couplings to connect PVC pipe to polypipe and some hoses.
    Directors can also connect reinforced pond hose between a PVC pressure pipe and a water tank bottom inlet to serve as a flexible coupling. See PHOTO 10.

    Popular with pool owners and gardeners. See PHOTOs 8 and 9.

    INLINE TAP Available for 13mm, 19mm and 25 mm poly pipe.
    Commonly used when a 19mm poly pipe is fitted to the flush outlet to collect sediment. The tap must be fitted to a horizontal length of poly pipe and not to a vertical drop as the trapped sediment will make the tap difficult to open and close. See PHOTO 7

    Connects to a PVC faucet fitting and snap fits to a hose connector. See PHOTO 10

    Joins a hose to a sprinkler adaptor.

    Connects two hoses. Also available as a reducing fitting to connect different size hoses.

    PHOTO 6: PVC and poly plain & reducing joiners.

    PHOTO 7: 45 degree elbows are fitted near the bottom of the drops to allow the horizontal pipe to clear the downpipe.

    Note that the horizontal pipe and fittings are shown above ground for clarity. The pipes are usually buried.

    PHOTO 8: Reducing tees can be fitted anywhere along a horizontal pipe’s length to connect to drip hoses.
    The plain reducing tee is connected to a 20mm PVC valve by a short PVC pipe. Another short PVC pipe then connects the valve to a faucet socket.
    This allows a 20mm BSP male threaded fitting to be screwed to the faucet socket. The sprinkler adaptor shown allows a hose to be connected.

    Photo 9: Neat and compact.

    PHOTO 10: Fitting an elbow allows the pipes to run parallel.

    PHOTO 11: Connecting a PVC pressure pipe to a tank’s ball or gate valve is easy.
    Screw a director into each end of a UV stabilised reinforced pond hose and then screw one director into the tank inlet and the other to a faucet socket. The faucet socket then slips over the PVC pipe.
    The pond hose serves as a flexible coupling and eliminates elbows.
    The tank inlet should be a minimum of 100mm above the bottom of the tank at its lowest point and within a 75 degree arc from the pump’s draw outlet.

    PHOTO 12: Neat and tidy.

    As in PHOTO 10, you can also create a very efficient inline sediment trap (Garden/Inline Filters)


    Selection depends on the total roof area harvested, the regions rainfall pattern and the intended use. For example, there would be little point in connecting a drop to a large horizontal pipe if the drop was supplying a drip hose that required no more than 4 litres per minute.
    If plumbing to tanks, it is best to base calculations on a one metre head as this generally represents a half full tank.
    The pipe length and all fittings cause friction/flow loss.

    CLASS 12 pressure pipes are sold at hardware stores and irrigation outlets. Always compare prices.
    CLASS 9 pressure pipes have the same outside diameter but their thinner walls give a greater internal volume. Rated at 900 kPa but are not available in 20mm.
    Both pipes use the same pressure fittings and depending on size, class 9 pipes are up to 40% cheaper but are not as widely available.
    Our DVD shows two 2,000 litre tanks in Melbourne metro supplied by a 32mm pressure pipe diverted to by two Supadivertas harvesting a combined roof area of 84 square metres.
    40mm pressure pipe is usually about 30% dearer than 32mm pressure pipe but some fittings can be cheaper.
    Higher volume class 9 pressure pipe generates higher flow rates than class 12 pipe.

    PHOTO 15:
    The tanks are buried 80mm and sit on a compacted sand base.
    A buried 32mm PVC pipe diverts to the two foreground 25mm & 32mm inlets.
    The rear tap attaches to a garden hose to top up the pool.

    PHOTO 16:
    What is underground?
    A 32mm poly director connects to a faucet adaptor and a 32mm reinforced pond hose. A second 32mm director (not shown) connects to the other end of the pond hose and to the elbow fitted to the tank’s inlet. The faucet adaptor is then fitted last to a plain tee fitted to the buried 32mm pipe.
    Note that the pond hose is not cut to length.


    Friction losses in pipe fittings are added to the pipe length to represent their equivalent friction loss as metres of pipe. For example, a 5 metre length of 40 mm PVC pipe fitted with two 90 degree elbows will have a total friction loss of the 5 metre pipe plus 2 x 1.3 metres for the two elbows, a total pipe length of 7.6 metres.
    Smart water saving and diversion
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