100mm Galvanised Steel Downpipe 70 Degree Bend

Creating an Offset

The positioning of the roofline relative to the house wall, where the gutter is installed, often requires an offset for attaching the downpipe. This offset distance varies based on the architectural design of the house.

Offsets in steel downpipe installations are available in four options:

1. 60mm: A 'fixed' offset suitable for 80mm and 100mm diameter pipes.
2. 60-210mm (or 255mm*): For slightly larger projections, a 'swan neck' offset can be achieved using two pipe bends, adjusting the angle and twist away from perpendicular (90°) to the wall.
3. 500-700mm: A new two-part variable offset solution.
4. Over 700mm: For larger projections, an offset can be created using a cut length of pipe inserted between two pipe bends.

When using two 70-degree bends (e.g., GST80B70), a 'swan neck' is formed to offset the downpipe from the roofline to the building wall:

• With an 80mm diameter downpipe, two bends allow for a maximum offset of 210mm.
• With a 100mm diameter downpipe, two bends allow for a maximum offset of 255mm*. (*Note: The combined height of two 70-degree bends forming a swan neck is 240mm.)

For offsets between 60mm and the mentioned maximums, the 'swan neck' inside the downpipe should be pivoted to the required distance from the wall, ensuring the outlet at the roofline is not directly above the downpipe but appropriately set off to the side.

The two-part adjustable offset in galvanised steel, available in seven robust coated colors for both 80mm and 100mm diameter pipes, accommodates offsets of up to 700mm.

For larger offsets, a cut section of downpipe can be inserted between the two bends, cut to the necessary additional length. (Note: Consider the overlap of the swaged necks of the downpipe piece and the bends in calculations.)