Which Cast Iron Radiator Should You Buy? A Complete UK Guide

Cast iron radiators are a bigger decision than most heating buys. They cost more, they last longer, and you will live with the choice for decades. This guide walks you through every part of it, so you can browse our cast iron radiator range knowing exactly what you are looking for.

Estimated reading time: 8 minutes

What actually makes a radiator cast iron?

Two very different products share the same name, and it causes no end of confusion.

A genuine cast iron radiator is made from individually moulded iron sections, bolted together and sealed. Each section is cast on its own. That is where the weight comes from, and the heat retention.

A cast iron style radiator is a steel column radiator shaped to look like one. Same silhouette from across the room. Different material, different weight, different behaviour.

Neither is better. They are answers to different questions.

We sell both, and we keep them apart on purpose. Our Bramwell Heritage collection is genuine cast iron, and that is what this guide covers. If you want the look without the weight or the cost, our column radiators do that job well and cost a good deal less.

Worth knowing which one you are shopping for before you start.

Are cast iron radiators efficient?

That is called thermal mass. And it matters.

Your room stays warm for longer. Your boiler fires less often. Across a winter, that adds up.

The heat feels different too. Cast iron releases warmth slowly and steadily, so the temperature in the room stays more consistent. There is less of the stop-start effect you get from lighter radiators that heat up and cool down quickly.

One honest caveat. Cast iron takes longer to reach temperature from cold. If you heat your home in short bursts, an hour in the morning and two in the evening, a lighter radiator may suit your habits better. Cast iron rewards steady heating over longer periods.

Worth thinking about how you actually heat your home before you commit.

How much does a cast iron radiator cost?

More than a panel radiator. Less than most people expect.

Across our Bramwell Heritage range, prices start at £110 and run to £2,632. That is a wide spread, and the reason is simple. You are buying by the section.

A small three-section radiator for a cloakroom sits at the bottom end. A thirty-section Oxford spanning more than two metres of wall sits at the top. Most rooms land somewhere in between.

Here is roughly how the cost breaks down:

• Sections: The main driver. More sections means more width, more heat and more cost
• Height: Taller models cost more per section
• Finish: Hand-painted standard colours cost less than custom RAL matching
• Valves and feet: Budget for these separately, they are not included

Set that against a mid-range designer panel radiator and cast iron is often closer than you would think, especially once you factor in how long it should last.

What sizes do cast iron radiators come in?

Cast iron works differently from a panel radiator. You do not pick from a handful of fixed sizes. You choose a height, then build the width section by section.

Across the Bramwell Heritage range:

• Heights: From 332mm on the Mayfair up to 760mm on the Victorian and Windsor
• Widths: From 3 sections to 30, spanning roughly 165mm to 2,340mm
• Section depth: Varies by model, from around 55mm to 78mm per section

That flexibility solves problems a panel radiator cannot.

Low window? The Mayfair is 332mm tall and built for exactly that.

Long empty wall in a hallway? An Oxford at 30 sections gives you 2,250mm of radiator in a single run.

Awkward alcove? Build the width to fit the gap rather than settling for the nearest standard size.

Measure the space first, then work out the output you need. The two together tell you the height and the section count. Our BTU calculator handles the output half.

Which colours and finishes can you choose?

This is where cast iron pulls away from everything else. The finish goes on after casting, so almost anything is possible.

We stock the classics ready to go:

• Black and anthracite: The modern default. Works against pale walls and in contemporary rooms
• White: The traditional choice. Settles quietly into a period interior
• Grey: Softer than black, warmer than white
• Brass, bronze and gold: Polished metallics for a radiator meant to be noticed
• Blue: For when the radiator is the accent, not the backdrop

And if none of those is right, our customisable cast iron radiators can be matched to any RAL colour. Pick up your cabinetry. Match your woodwork. Contrast on purpose.

A word on upkeep. Different finishes behave differently. White shows dust sooner, and we have written a guide on keeping a white cast iron radiator clean. Painted finishes handle humidity well, so bathrooms are no problem. Unfinished or polished-only metallics are best kept out of wet rooms unless they are properly sealed.

How many columns do you need?

Columns, sometimes called bars, are the depth of each section. More columns means more surface area, which means more heat from the same width of wall.

Two columns is slim. Three is the common middle ground.

In the Bramwell Heritage range, the Victorian gives you the choice of 3 bar or 4 bar across six different heights. The other models have their column profile built into the design. It is part of what makes an Oxford look like an Oxford.

The trade-off is simple. More columns gets you more heat but projects further into the room. In a narrow hallway that matters. In a living room it usually does not.

Short on wall width? Go deeper. Short on floor space? Go wider and shallower.

What valves, feet and wall stays will you need?

The bit people forget, and then ring us about on installation day.

Cast iron radiators do not come with valves. You choose them separately, and on a radiator this visible the valve is part of the look.

What you will need:

• Valves: A pair, angled or straight depending on your pipework. Traditional antique-style valves suit these radiators far better than a modern chrome TRV
• Feet: Most cast iron stands on floor-mounted feet rather than hanging off wall brackets
• Wall stays: Not load-bearing, but they stop the radiator tipping. Fit them
• Bleed valves and blanking plugs: To close off the tappings you are not using
• Shrouds: Cover the pipework where it meets the floor. Optional, but it finishes the job properly

Match the metal across all of it. Antique brass valves with antique brass feet. Chrome with chrome. Mixing finishes is the quickest way to make an expensive radiator look cheap.

Fitting it yourself? Our step-by-step installation guide covers the process from start to finish.

Which Bramwell radiator suits your home?

Five models. Each one answers a different problem.

→ Mayfair : for low windows and awkward spaces. At 332mm it is the shortest in the range, built for under bay windows and below low sills where nothing else fits. Ornate detailing despite the low profile. Widths from 3 to 30 sections. From £176.

→ Victorian  : the flexible starting point. Six heights from 450mm to 760mm, a choice of 3 bar, and widths up to 30 sections. The most configurable radiator we stock, and the most affordable way into genuine cast iron. From £110.

→ Piccadilly : the traditional all-rounder. A single 680mm height and widths to 2,100mm. Classic proportions and no decisions to agonise over. If you simply want a cast iron radiator that looks right in a period room, start here. From £187.

→ Windsor : period detail, modern proportions. Available at 560mm and 760mm, with the deepest sections in the range at 78mm. Substantial without being fussy. Works as well in a modern kitchen as a Victorian hallway. From £200.

→ Oxford : the statement piece. The most ornate casting we sell, at 460mm or 660mm, and the widest span available. 30 sections gives you 2,250mm in a single run. This is the one for a hallway you want people to notice. From £239.

Still undecided? Start with the room, not the radiator. Measure the wall, run the BTU calculator, then pick the model whose height fits the space you have.

Working on a period property? Our guide to choosing radiators for period homes and our comparison of Georgian, Victorian and ornate styles both go deeper than we can here.

Do cast iron radiators work with a heat pump?

Yes, but sizing matters far more than it does on a gas boiler.

Heat pumps run at lower flow temperatures. A gas boiler might send water out at around 70°C. A heat pump typically runs closer to 45 to 50°C. Less heat in the water means you need more radiator surface to put the same warmth into the room.

For cast iron, that usually means more sections than you would fit on a boiler system. Sometimes considerably more.

The thermal mass works in your favour here. Heat pumps prefer to run steadily over long periods rather than in short blasts, and steady is exactly what cast iron is good at.

But get the sizing wrong and you will have a cold room and an expensive radiator. Speak to a qualified heating engineer before you commit. They will calculate the output you need at your system’s actual flow temperature.

We also stock a range selected for heat pump systems if you would rather not do the maths.

Should you buy new or reclaimed?

Reclaimed cast iron radiators have real appeal. Genuine age, genuine patina, and often a lower price.

They also carry risks worth knowing about.

An old radiator has spent decades full of system water. Internal corrosion and sludge are common. Most need stripping, flushing and pressure testing before they are safe to install, and that costs money. Some fail the test.

You also inherit whatever the previous system did to them. There is no guarantee, no recourse, and no way to order a matching second one for the other side of the room.

New cast iron gives you the same material and the same look, cast to the same patterns. Ours are hand painted and pressure tested before they leave us, and they come with a guarantee behind them.

If you want authentic salvage and you are prepared to restore it, reclaimed is a genuine option. If you want the look without the gamble, buy new.

Ready to find your cast iron radiator?

If cast iron sounds like the right fit, come and have a look at the range.

Every radiator we sell is third-party tested. Our cast iron comes with a 15-year manufacturer’s guarantee, free UK mainland delivery and 90-day returns as standard, and we hold a Trustpilot score of 4.8 out of 5.