Alumasc Cast Aluminium Half Round Guttering

The Alumasc Cast Aluminium Half Round Gutter is one of the most popular and timeless gutter profiles—valued for its traditional shape, smooth water flow, and compatibility with a wide range of building styles.

Lightweight and corrosion-resistant, this heritage guttering offers the elegance of period detailing with the practical advantages of modern aluminium systems.

Whether you're restoring a listed building or designing a new home with classic touches, the aluminium half round profile delivers both form and function.

✅ Authentic shape – the most traditional gutter profile
✅ Manufactured by Alumasc to BS 2997:1958 (1980)
✅ BBA-approved polyester powder-coated finishes available
✅ Low maintenance, long-lasting, and fully recyclable aluminium
✅ Ideal for heritage projects or modern builds with classic features

What Is Half Round Guttering?

Half round guttering gets its name from its simple, semi-circular profile. This design has been used for centuries across domestic, ecclesiastical, and civic architecture thanks to its efficient water flow and understated visual appeal.

The Alumasc half round system replicates the look of traditional cast iron, making it a perfect choice for conservation areas, listed buildings, and period homes—but it's also versatile enough for modern developments seeking timeless design elements.

Why Choose Alumasc Cast Aluminium Half Round Guttering?

✔ Traditional Look, Lightweight Feel

This system delivers the aesthetic of traditional cast iron without the associated weight, making it easier to install and maintain.

• Manufactured in the UK from recycled aluminium

• Non-corrosive and designed to last for up to 40 years in rural and suburban environments

• Available in plain mill finish or factory-applied powder coatings

✔ BBA-Approved Powder Coated Finishes

Alumasc’s BBA-approved polyester powder coating process (Ref: 86/1671) ensures long-lasting colour performance and protection.

Colour options include:
🎨 Textured Black (next day delivery - order by 11:30am)
🎨 5 other textured colours (10-15-day lead time)
🎨 26 Standard Matt RAL Colours (10-day lead time)
🎨 Special order BS or RAL shades available on request
🎨 Cast iron effect finish (available in black only for added authenticity)

This flexibility allows the guttering to either blend with modern features or faithfully replicate traditional metalwork.

Designed for Heritage Projects & Modern Builds

The Heritage range of Alumasc cast aluminium round guttering is specifically developed to match the architectural features of traditional buildings, while also being practical for fast-track, modern construction.

🏡 Ideal for:

• Listed and conservation buildings

• Renovations and barn conversions

• Traditional-style new builds

• Both flush and projecting eaves

It also pairs seamlessly with Heritage downpipes, featuring extruded aluminium with cast sockets for a fully compatible, cohesive rainwater system.

Installation Made Simple

This system is designed with installers in mind.

• Wet sealed and bolted joints ensure a leak-free finish

• Use 3 brackets per length, spaced at 915mm centres, with extra support at outlets and angles

• Separate sockets provide flexibility and precision during fitting

• Compatible with a wide selection of fixing clips and eared sockets

🔩 Don’t forget the fixings:

• Use low modulus silicone sealant (e.g. DOW791Wet-sealed) and M6 x 20mm aluminium bolts, nuts, and washers (Product Code: ALBOLT20)—all available in our Guttering Accessories section