Cast iron downpipes remain one of the most additions on most traditional buildings. Get the profile right and the whole rainwater system feels balanced. Get it wrong and even expensive guttering can end up looking cheap against the property! That’s why genuine cast iron still gets specified so heavily across listed buildings, conservation projects, churches, period homes, and heritage developments throughout the UK.
At Cast Iron Warehouse, we supply the Alumasc Apex Heritage cast iron downpipe range in both round and rectangular profiles, alongside matching cast iron hopper heads, shoes, bends, offsets, brackets, and fittings for complete cast iron rainwater systems. This system is manufactured using proper, authentic sand cast methods and produced to BS460 standards.
Available in 65mm, 75mm, and larger 100mm cast iron downpipe sizes, the range suits everything from smaller residential properties through to larger commercial and heritage buildings requiring higher rainwater capacity.
Unlike imitation cast iron effect downpipes, genuine cast iron offers proper depth, weight, and long-term exterior performance. The socketed joints, textured finish, and heavier wall thickness create a far more authentic appearance once installed, especially on older buildings where architectural detail matters. Next Day delivery on stocked sizes and finishes.
Alumasc Apex 75mm (3") Cast Iron Loose Socket with Ears - Primed
Sale price £17.95 Regular price £24.83Unit priceAlumasc Apex 75mm (3") Cast Iron Loose Socket without Ears - Primed
Sale price £17.95 Regular price £24.83Unit priceAlumasc Apex 75mm (3") Cast Iron Downpipe Eared Shoe - Primed
Sale price £49.25 Regular price £68.13Unit priceAlumasc Apex 75mm (3") Cast Iron Downpipe Shoe without Ears - Primed
Sale price £49.25 Regular price £68.13Unit priceAlumasc Apex Left-hand 75mm (3") Cast Iron Downpipe Rainwater Divertor - Primed
Sale price £80.33 Regular price £111.13Unit priceAlumasc Apex Right-hand 75mm (3") Cast Iron Downpipe Rainwater Divertor - Primed
Sale price £80.33 Regular price £111.13Unit priceAlumasc Apex 75mm (3") Cast Iron Access Pipe 400mm long with Ears - Primed
Sale price £116.60 Regular price £161.31Unit priceAlumasc Apex Right-hand 65mm (2.5") Cast Iron Downpipe Rainwater Divertor - Primed
Sale price £80.33 Regular price £111.13Unit priceAlumasc Apex 100mm (4") x 1.83m Cast Iron Downpipe with Ears - Black
Sale price £162.11 Regular price £224.26Unit priceAlumasc Apex 100mm (4") x 1.83m Cast Iron Downpipe without Ears - Black
Sale price £162.11 Regular price £224.26Unit priceAlumasc Apex 100mm (4") Zinc Plated Steel Downpipe Bracket for Cast Iron - Black
Sale price £34.62 Regular price £47.89Unit priceAlumasc Apex 100mm (4") Cast Iron 90 degree Bend without Ears - Black
Sale price £63.08 Regular price £87.26Unit priceAlumasc Apex 100mm (4") Cast Iron 112 degree Branch without Ears - Black
Sale price £62.31 Regular price £86.19Unit priceAlumasc Apex 100mm (4") Cast Iron 135 degree Bend without Ears - Black
Sale price £63.08 Regular price £87.26Unit priceAlumasc Apex 100mm (4") Cast Iron 112 degree Bend without Ears - Black
Sale price £63.08 Regular price £87.26Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 75mm (3") Projection - Black
Sale price £108.14 Regular price £149.60Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 115mm (4.5") Projection - Black
Sale price £108.14 Regular price £149.60Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 150mm (6") Projection - Black
Sale price £108.14 Regular price £149.60Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 225mm (9") Projection - Black
Sale price £138.68 Regular price £191.85Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 305mm (12") Projection - Black
Sale price £172.29 Regular price £238.35Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 380mm (15") Projection - Black
Sale price £212.84 Regular price £294.44Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 455mm (18") Projection - Black
Sale price £235.40 Regular price £325.66Unit priceAlumasc Apex 100mm (4") Cast Iron Loose Socket with Ears - Black
Sale price £30.14 Regular price £41.70Unit priceAlumasc Apex 100mm (4") Cast Iron Loose Socket without Ears - Painted Black
Sale price £30.14 Regular price £41.70Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Shoe without Ears - Black
Sale price £84.04 Regular price £116.26Unit priceAlumasc Apex 100mm (4") Cast Iron Access Pipe 400mm long with Ears - Black
Sale price £177.81 Regular price £245.98Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Eared Shoe - Black
Sale price £84.04 Regular price £116.26Unit priceAlumasc Apex Right-hand 100mm (4") Cast Iron Downpipe Rainwater Divertor - Pre-painted Black
Sale price £89.34 Regular price £123.60Unit priceAlumasc Apex 100mm (4") x 1.83m Cast Iron Downpipe with Ears - Primed
Sale price £130.60 Regular price £180.68Unit priceAlumasc Apex 100mm (4") x 1.83m Cast Iron Downpipe without Ears - Primed
Sale price £130.60 Regular price £180.68Unit priceAlumasc Apex 100mm (4") Zinc Plated Steel Downpipe Bracket for Cast Iron - Primed
Sale price £27.92 Regular price £38.62Unit priceAlumasc Apex 100mm (4") Cast Iron 90 degree Bend without Ears - Primed
Sale price £51.71 Regular price £71.53Unit priceAlumasc Apex 100mm (4") Cast Iron 112 degree Branch without Ears - Primed
Sale price £63.76 Regular price £88.20Unit priceAlumasc Apex 100mm (4") Cast Iron 135 degree Bend without Ears - Primed
Sale price £51.71 Regular price £71.53Unit priceAlumasc Apex 100mm (4") Cast Iron 112 degree Bend without Ears - Primed
Sale price £51.71 Regular price £71.53Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 75mm (3") Projection - Primed
Sale price £87.04 Regular price £120.41Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 115mm (4.5") Projection - Primed
Sale price £87.04 Regular price £120.41Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 150mm (6") Projection - Primed
Sale price £87.04 Regular price £120.41Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 225mm (9") Projection - Primed
Sale price £111.56 Regular price £154.34Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 305mm (12") Projection - Primed
Sale price £138.62 Regular price £191.76Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 380mm (15") Projection - Primed
Sale price £171.31 Regular price £237.00Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Offset 455mm (18") Projection - Primed
Sale price £189.40 Regular price £262.03Unit priceAlumasc Apex 100mm (4") Cast Iron Loose Socket with Ears - Primed
Sale price £24.29 Regular price £33.60Unit priceAlumasc Apex 100mm (4") Cast Iron Loose Socket without Ears - Primed
Sale price £24.29 Regular price £33.60Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Eared Shoe - Primed
Sale price £67.62 Regular price £93.54Unit priceAlumasc Apex 100mm (4") Cast Iron Downpipe Shoe without Ears - Primed
Sale price £67.61 Regular price £93.53Unit priceAlumasc Apex 100mm (4") Cast Iron Access Pipe 400mm long with Ears - Primed
Sale price £161.57 Regular price £223.51Unit priceAlumasc Apex Right-hand 100mm (4") Cast Iron Downpipe Rainwater Divertor - Primed
Sale price £80.33 Regular price £111.13Unit priceAlumasc Apex 65mm (2.5") x 1.83m Cast Iron Downpipe with Ears - One of 6 CI Standard RAL Colours TBC
Sale price £122.28 Regular price £169.17Unit priceAlumasc Apex 65mm (2.5") x 0.9m Cast Iron Downpipe with Ears - One of 6 CI Standard RAL Colours TBC
Sale price £101.07 Regular price £139.82Unit price

Why Choose Alumasc Apex Cast Iron Downpipes?
Cast Iron Rainwater Frequently Asked Questions
How Quick Is Delivery?
How Quick Is Delivery?
Popular painted black cast iron guttering sizes are typically available for next working day delivery across the UK when ordered before 11:30am, subject to stock availability.
Primed systems are stocked across selected sizes, while custom RAL powder coated cast iron guttering is usually supplied within 7–10 working days.
What Makes Apex Heritage Different From Cheaper Cast Iron Systems?
What Makes Apex Heritage Different From Cheaper Cast Iron Systems?
We think the consistency is noticeably better. Apex Heritage cast iron guttering is manufactured using traditional sand cast methods alongside modern quality control standards, giving cleaner alignment, more reliable fitment, and a far better painted finish compared with lower-grade imported systems.
What Size Cast Iron Guttering Do I Need?
What Size Cast Iron Guttering Do I Need?
For most standard residential properties, 115mm (4½”) Half Round cast iron guttering is the most commonly used size. Larger roofs, commercial buildings, or areas with heavier rainfall may benefit from 125mm or 150mm systems. If you're replacing existing guttering, matching the current profile and outlet size is usually the safest option.
Is Cast Iron Better Than Cast Iron Effect Plastic Guttering?
Is Cast Iron Better Than Cast Iron Effect Plastic Guttering?
They’re completely different products really. Plastic cast iron effect guttering is lighter and cheaper upfront, but genuine cast iron is significantly stronger, longer lasting, and far more authentic visually. Proper cast iron guttering can last well over 40 years and suits heritage buildings far better than imitation systems.
Are Custom Colours Available?
Are Custom Colours Available?
Yes. Custom RAL colour cast iron guttering is available for heritage and architectural projects requiring a more bespoke finish. These systems are professionally powder coated in the UK with typical lead times of 7–10 working days.
How Heavy Is Cast Iron Guttering?
How Heavy Is Cast Iron Guttering?
Cast iron guttering is substantially heavier than plastic or aluminium systems, which is part of why it lasts so long. Proper bracket spacing and secure fixing into suitable surfaces is important for long-term performance.
How Long Does Cast Iron Guttering Last?
How Long Does Cast Iron Guttering Last?
High quality cast iron guttering systems regularly achieve service lives exceeding 40 years when correctly installed and maintained. Many older cast iron systems remain in use well beyond that.
What Happens If I Order The Wrong Parts?
What Happens If I Order The Wrong Parts?
Returns are accepted within 30 days on standard stock items. Orders returned within 14 days are generally accepted without a restocking charge, while returns after 14 days may be subject to a handling fee depending on the products ordered.
Do You Offer Trade Support?
Do You Offer Trade Support?
Yes. We work closely with builders, roofing contractors, installers, architects, and developers needing specification support, bulk pricing, and reliable lead times across larger cast iron rainwater projects.