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Established 1893   |   BS 460:2002 Certified   |   UK & International Supply   |   Expert Technical Support   |   0333 987 4452

Shop / Cast Iron Gutters & Pipes / Cast Iron Round Downpipes / Cast Iron Round Downpipe Offset – 457mm (18″) Projection
Cast Iron Pipe Offset Swan Neck
How to measure the projection of a cast iron round downpipe offset, centre line to centre line
CODE RWOS18 Category Cast Iron Round Downpipes

Cast Iron Round Downpipe Offset – 457mm (18″) Projection

£220.90 – £354.20Price range: £220.90 through £354.20 ex VAT (£265.08 – £425.04 inc VAT)

Our cast iron round rainwater pipe offset 457mm and iron downpipe offset is suited to most period property renovations. Round cast iron pipe is available in primed and black as standard.
Sizes Available:

65mm (2.5″)
75mm (3″)
100mm (4″)

Our traditional cast iron rainwater pipe is available in 4 sizes. It is now common to see 2.5″ pipes used in place of the older 2″ sizing.

Measuring the projection: measured horizontally between the centre lines of the upper and lower pipe, not face to face. See the measuring diagram in the gallery, or our guide to measuring an offset for all sizes and a worked example.

Clear

UK delivery from £30. Fittings are despatched boxed. See delivery rates.

Our traditional cast iron rainwater pipe is available in 3 sizes. It is now common to see 2.5″ pipes used in place of the older 2″ sizing.

Cast iron gutters and pipes offer great strength and durability, a proven history of long life, low noise operation and fire resistance. Most old buildings have cast iron rainwater systems that should be maintained and preserved however; these inherent benefits make a cast iron rainwater system an ideal choice for both traditional and modern installations.

Technical

For specific technical sizes on our range of cast iron gutters, rainwater pipes or UK manufactured brackets for cast metal rainwater products.

Additional information

Pipe Size/Finish

Primer 65mm, Primer 75mm, Primer 100mm, Black Painted 65mm, Black Painted 75mm, Black Painted 100mm

Cross-reference

Primer 65mmR2546
Primer 75mmR3046
Primer 100mmR4046
Black Painted 65mmXR2546
Black Painted 75mmXR3046
Black Painted 100mmXR4046

FAQ Categories

  • Cast Iron Airbricks
  • Cast Iron Airvents
  • Cast Iron Hopper Heads
  • General
  • Gutter & Pipe Brackets
  • Gutters & Pipes
  • Heating
  • Rooflight Openers
  • Soil Pipes
All FAQ
What building types is the H527 cast iron hopper head suited to?

What building types is the H527 cast iron hopper head suited to?

The H527 measures 430mm wide x 195mm deep x 540mm high, making it well suited to Victorian villas and townhouses where a decorative leader head is wanted.

What building types is the Iron Works Hit & Miss Vent in Polished Lacquered suited to?

What building types is the Iron Works Hit & Miss Vent in Polished Lacquered suited to?

The Polished Lacquered finish suits buildings where period ironwork was finished bright rather than painted — formal entrance elevations, listed properties, and settings where the grille contributes to the decorative programme of the facade. It is appropriate for conservation specifications and high-specification heritage new build.

What building types is the H525 cast iron hopper head suited to?

What building types is the H525 cast iron hopper head suited to?

The H525 measures 270mm wide x 208mm deep x 285mm high, making it well suited to smaller period properties, extensions and outbuildings.

What building types is the Cast Iron Louvre Airbrick suited to?

What building types is the Cast Iron Louvre Airbrick suited to?

The Cast Iron Louvre Airbrick suits Victorian and Edwardian terraced housing, semi-detached properties, public houses, agricultural buildings, and workshop structures where the original airbrick was a louvre-face grille. The horizontal fin profile is widely found in British domestic and light industrial construction from the 1870s through to the 1950s.

Where should access pipes be fitted on a downpipe?

Where should access pipes be fitted on a downpipe?

At the foot of each stack above the shoe or gully, directly above offsets and bends, and below hopper heads where trees overhang the roof. On tall or long runs, an extra access point part-way up makes clearance easier.

What building types is the H540 cast iron hopper head suited to?

What building types is the H540 cast iron hopper head suited to?

The H540 measures 600mm wide x 340mm deep x 475mm high, making it well suited to substantial country houses, civic and ecclesiastical buildings.

What building types is the Brass Rooflight Hand Winder Opener – Telescopic suited to?

What building types is the Brass Rooflight Hand Winder Opener – Telescopic suited to?

This opener is particularly well suited to period and heritage properties — Georgian and Victorian terraces, conservation area houses, traditional orangeries, and listed buildings where a brass finish is required to complement existing ironmongery. It is compatible with Lumen Rooflights and most timber-framed skylights.

What sizes of cast iron soil pipe do you supply?

What sizes of cast iron soil pipe do you supply?

LCC soil pipe and fittings are available in 50mm, 65mm, 75mm, 90mm, 100mm and 150mm. Traditional Express is available in 50mm and 100mm. LCC pipe comes in 1829mm, 1219mm, 914mm and 610mm lengths, with eared and plain double socket lengths for cutting on site.

What if my building’s existing gutter profile isn’t in your standard range?

What if my building’s existing gutter profile isn’t in your standard range?

Where a standard profile can't match an existing design, we offer a bespoke casting service in association with our pattern makers, typically with a 12–14 week lead time. Please call 0333 987 4452 or use the contact form to discuss your project.

What is the Premier Extra finish?

What is the Premier Extra finish?

Premier Extra is our ready-to-fix factory finish — an attractive black semi-gloss coating that needs no painting on site, available across all seven standard gutter profiles and round rainwater pipes. It's also available to special order in a wider range of RAL and BS colours.

Related products

  • Round Pipe Strap Bracket, TRB108

    Round Pipe Strap Bracket

    £26.53 – £27.34Price range: £26.53 through £27.34 ex VAT (£31.84 – £32.81 inc VAT)
    Select options This product has multiple variants. The options may be chosen on the product page
  • Cast Iron Round Rainwater Downpipe Shoe Plain

    Cast Iron Round Downpipe Shoe – Plain

    £64.20 – £97.90Price range: £64.20 through £97.90 ex VAT (£77.04 – £117.48 inc VAT)
    Select options This product has multiple variants. The options may be chosen on the product page
  • Cast Iron Round Pipe Socket Plain

    Cast Iron Round Downpipe Loose Socket – Plain

    £27.10 – £48.70Price range: £27.10 through £48.70 ex VAT (£32.52 – £58.44 inc VAT)
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Find out more about our products by giving us a call
0333 987 4452

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