The damage rainwater can wreak on a building has been acknowledged for centuries, and the age-old question remains the same: steel vs. aluminium gutters, which one is the best option? The practice of diverting it away from buildings has been in place since the Roman Empire, but modern gutters weren’t actually technically invented until the 20th Century.

The guttering material of choice back then was cast iron, which due to its weight and price was eventually replaced, for all but prestigious heritage projects, by a whole host of options, mostly steel, aluminium and plastic, but also zinc and copper.

What Factors To Consider When Comparing Steel Vs Aluminium Gutters

Differences Between Steel Vs Aluminium Gutters Primary Material

What are the differences between steel vs aluminium gutters? Deciding on the best material option for a property’s gutters begins with a closer look at the primary material differences and how they can affect long-term outcomes.

Steel was long thought of as the go-to material for gutters due to its durability, corrosion resistance and toughness. It can also be galvanised with a protective zinc coating to reduce the likelihood of rust build-up over time.

Aluminium gutters hit the market more recently, in the 1960s. Widely acknowledged as a lightweight but durable metal that functions as an efficient heat conductor, it is also more easily roll-formed than steel and is non-magnetic.

Perhaps the overriding factor for some when comparing steel vs aluminium gutters is the upfront cost, and typically, aluminium tends to be slightly less expensive overall, perhaps two-thirds of the price of steel. But there are other factors in its favour.

Installation-wise, aluminium is considerably lighter and innately more flexible than steel which makes the fitting process less involved, so much so that many property owners prefer to install it themselves rather than pay professional installers. 

Weather-Resistance

Climate is another important factor to be considered when comparing steel vs aluminium gutters. Steel gutters, and galvanized steel products, are resilient in extreme weather conditions, and it seems a consensus that the earth is experiencing more of these. But steel gutters tend to rust over time so while they may hold up better, literally, in severe winter and icy conditions, the standing ice, snow and water can speed up the oxidation process and lead them to rust more quickly.

Subsequently, steel gutters need a bit more maintenance. Standing water should not be allowed for long periods of time. And where there is a zinc coating, this should be regularly inspected, and any new rust spots dealt with appropriately.

Conversely, aluminium is a rust-proof metal, and consequently more low maintenance than steel. And, while aluminium is more prone to denting, it is still very durable– the thickest aluminium gutters can endure fallen tree branches, heavy snowfall and ice.

In climates with extreme temperature fluctuations, aluminium will expand and contract more than steel, but this variation, and its propensity for leaks at joints or seams, can be designed out by professional installers. While steel gutters can be installed as a seamless system, specialised transport may be required to deliver the long sections to site.

Form & Colour

Functionality aside, you may ask whether there are any other differences when comparing steel vs aluminium gutters. In fact, the form also requires consideration, as the specific design features of a building can dictate whether aluminium or steel gutters are used.

It’s important to scrutinise the surrounding materials that will come in contact with the gutters as both steel and aluminium will have galvanic reactions when installed in proximity with dissimilar metals such as zinc and copper, which are increasingly being specified by design-led architects for roofs and cladding.

For instance, when steel encounters copper, a galvanic reaction will cause it to rust out faster, while aluminium, though not completely compatible with copper, will not have nearly the reaction as that steel and copper.

Aesthetically, colour choices are the same with steel as they are with aluminium, with the option for both to be custom painted to complement or contrast the colour