How to choose your radiator material

Radiators now come in many different shapes, sizes and colours, but they are only constructed from four different materials: cast iron, steel, stainless steel or aluminium. But what are the pros and cons of each, and which material should you choose for your radiators?

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Cast iron

Early radiators were usually made of cast iron. It retains heat for a long time and releases it slowly, so it was the ideal material for use in draughty Victorian properties to keep the heat in the fabric of the building. This also means that the boiler doesn’t have to work as hard once the house has warmed up. However, cast iron is very heavy and takes a long time to warm up, and the radiators also take up more space than others.

Mild steel

Mild steel is the most common material used in radiators today and accounts for most of the flat panel radiators that you see in homes. It’s relatively inexpensive, lends itself to different shapes and styles, and heats up quickly. The downsides are that it loses heat faster than cast iron, and you need to keep the system topped up with corrosion inhibitor to prevent internal rust.

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Aluminium is a very good conductor of heat, so aluminium radiators such as those from heat up very quickly, giving you a fast response from your heating system when you turn up the thermostat. Other advantages are that aluminium is corrosion resistant and aluminium radiators are lighter and easier to install than other types. They can come in a variety of colours and styles, so can be used in almost any type of property; however, they are more expensive than mild steel radiators.

Stainless steel

Stainless-steel radiators combine some of the advantages of the aluminium and mild steel radiators. They warm up quickly and don’t rust. Stainless-steel radiators also retain heat longer than aluminium ones and are easy to maintain and keep clean as they only require an occasional wipe down. However, these are the most expensive type of radiator.

Your choice of material for your radiators will be a balance between function and price. Aluminium heats up faster and responds quickly to the heating controls, cast iron retains heat for longer, stainless-steel is effective and durable but expensive, and mild steel offers a balance between price and performance.