Downpipe Adaptor Square to Round

Stormwater Downpipe Adaptors

Our stormwater downpipe adaptors connect downpipes to standard stormwater drainage systems.

• How it works: The downpipe fits inside one end of the adaptor, while the stormwater pipe fits inside the other end.

• Understanding sizes: The variant options refer to the downpipe size first, followed by the stormwater pipe size it connects to.

   (For example: "100mm x 50mm - 90mm" = Square Downpipe of 100mm X 50mm connects to a 90mm stormwater pipe)

About Stormwater Pipe and Fittings:

• Made from rigid PVC-U (unplasticised PVC), designed specifically for rainwater drainage.

• Available in sizes ranging from 75mm to 150mm, with 90mm being the most common size for domestic use.

• 90mm fittings are compatible with 90mm slotted pipe for garden and drainage applications.

• Compliant with AS/NZS 1254 standards for stormwater piping.

Installation Notes:

• Pipes and fittings are joined using solvent cement (SCJ – Solvent Cement Joint system).

• Allow 24 hours after assembly for full mechanical strength.

• Suitable for above-ground and underground installation.

• Can be exposed to sunlight, though long-term exposure is not recommended.

Other Key Information:

• All “90-degree” fittings are manufactured slightly less than 90° (typically 85–88°) to promote proper water flow and avoid pooling.

• PVC-U stormwater systems offer excellent resistance to corrosion, chemicals, and biological growth, with the added benefits of easy handling, strength, and flexibility.