Thinking about replacing your existing radiators. Want advice on choosing between vertical radiators and horizontal radiators. Here we will look at the various factors and give you the answers that will allow you to decide which are best for you.

Today a radiator can make a clear design statement in either a horizontal or vertical form. This is true for traditional radiators, but state of the art far-infrared heating panels go beyond this being free from many of the old design limitations. Radiators have become items of room decor that say as much about you as your choice of soft furnishings. And they heat the room as well.

Vertical radiators have become on trend. But is this just a fashion statement? Are they as practical as the more common horizontal choice?

Which type of radiator is best - vertical or horizontal?

The bottom line is, will a radiator bring warmth and comfort to your room?

Radiators are traditionally classified in BTUs, or British Thermal Units. This is the normal unit of heat that a radiator will output to a room. Alternatively, radiators may be rated in Watts or Joules or Kilojoules.

Regardless of whether you are installing vertical or horizontal radiators, it is the BTUs that needs to be considered when heating the room.

Therefore the first thing you need to figure out is how many BTUs are required to heat your room to a comfortable level. Luckily there are a number of BTU calculators around the web that will help you out with this.

Once your BTU is known, you can then select the radiator that matches your room. Be it vertical or horizontal, it is really an aesthetic choice.

What are horizontal radiators?

A horizontal radiator is the familiar long radiator that everyone knows. This is the safe option. 

They are often situated underneath windows to counteract the downdraft, but when curtains are drawn over them they become inefficient. The radiator also gets blocked by furniture like sofas, which are often placed there to disguise the utilitarian look of steel panel radiators. 

Why choose a horizontal radiator?

In terms of practical design, a horizontal radiator is the ideal solution to a cold and draughty window. In the past, single glazing cooled the air next to it. As cold air is denser, it fell to the ground as a downdraft. Old sash windows were also prone to other draughts creaking past their inefficient joints. The solution was to place a radiator under the window, so that the rising hot air would heat the draught. Sadly a lot of the heat was lost straight out of the window.

Today double and treble glazing with their sealed frames have solved the cold window issue.

In terms of decor, as radiators evolved they became utilitarian and just plain ugly. The result was that they tended to get hidden behind furniture and curtains that stopped the heat reaching the room. Now radiators are designed to be seen, so there is no need for them to be hidden.

The lowest cost option when replacing radiators is to replace these width-for-width. But if you are doing this with horizontal radiators, then consider that you may wish to rearrange the layout of the moveable elements in your room to make more of the visual statement a modern radiator design will give.

A horizontal radiator is good when you:

• Just want to replace a radiator that has seen better days.
• Can do the basic replacement connections yourself and want to save any further expense.
• Need the job to be done quickly.
• Wish to give a traditional look.

What are vertical radiators?

If you can picture a traditional horizontal radiator, then all you need to do is turn on its side and you have the concept of a vertical radiator. In practical terms it is slightly more difficult than that as the designers have to consider how the water will circulate through the radiator.

The more obvious position of vertical radiators means that you have to consider how their look will interact with the other design elements of your room. The plus point is that as they take up less wall length, you will have more options in locating other furnishings in the space.

Why choose a vertical radiator?

The vertical design allows the heat to flow from the radiator to the rest of the room. The heat is not insulated from the room by furnishings. As the radiators run for more of the height of the walls, this allows warm air currents to circulate more freely around the room. Therefore, cold spots are less likely.

It also gives you another design element to incorporate into your room. There are sufficient variations in vertical radiator designs to allow this to be subtle, or bold. The choice is yours.

A vertical radiator is good when you:

• Have limited available wall length - ideal for smaller spaces.
• Need to supply a lot of BTUs to the room.
• Wish to use it in a bathroom, where the design may incorporate towel rails.
• Want to use it as a clear design statement, from minimalist to steam-punk.
• Add value to your home by being on trend.

Are vertical radiators less efficient than horizontal radiators?

It is often said that vertical radiators won’t give out the same heat output as horizontal radiators. 

This opinion is based on the fact that they don’t have the same length to draw cold air up using convection. However, as the air column is heated for a longer length with vertical radiators, the air heats to a higher temperature and moves faster. Therefore the warming air current has enough speed to move around the room, not just sit at the ceiling waiting to cool.

Vertical radiators also do not tend to get hidden behind insulating furniture. 

At the end of the day, a well designed radiator, placed and sited in a good location, is the real efficient factor in design. And this has little to do with the shape of the radiator itself.

What are the best heating radiators?

This is dependent on designing the best heating solution for the room. A heating calculator may say a room needs 9,000 BTUs. But it would be impractical to have one massive large radiator to heat the room. This becomes more critical the more a room deviates from a square box. If a room becomes an L shape then the complexity is increased.

You also need to consider how the room will be used, and how it will be furnished. Is the room glazed on one, two, three or four walls? Where are the doors placed? When you know all these things you will have an idea where you want the warm air to flow. 

Traditional radiators are actually convectors for most of their output, and it is this flow of warm air that heats the room. Infrared heating panels on the other hand are true radiators, as they heat what the infrared light touches. This further radiates heat and convects hot air to heat the room.

When you evaluate these elements you are now able to determine if your room is best heated by a number of smaller radiators in a few key locations.

What styles exist for vertical and horizontal radiators?

There are an ever increasing number of style choices in radiators. But they come in three style types:

• Column radiators - The traditional style radiators, made of a number of columns joined at the top and bottom. There can be one or several rows of columns in the depth of the radiator. These have that solid chunky look, and can blend in well with older style of buildings where they compliment the other design keys. On the other hand they can be given non-standard finishes that can make them fit in with a loud contemporary look, or given a steam-punk makeover as well.
• Flat panel radiators - Are the modern twist where thin flat sections are used to maximise the surface area, and thermal transfer of the radiator. Like column radiators they can come in multiple width rows. By nature these look modern and quite minimalist, and fit into most decors more subtly.
• Convector radiators - Are where additional fins are added to a panel, or more rarely column. These fins provide additional surface area, and boost the convection hot air flow that the radiator naturally generates. This solution is best if you want to cut down on the amount of radiators you have, or have a high heating need.

What are the costs of vertical and horizontal radiators?

This is generally a production cost element. As more horizontal radiators are made, their unit cost is lower than a vertical radiator. This can be between 10% to 40%.

The lifespan of a working radiator can be evaluated in terms of decades, so the efficient design of your heating solution is a far more important cost factor. 

What is your final choice - vertical or horizontal?

In a practically designed heating system a vertical radiator will be no less efficient at warming a room than a horizontal one. 

Vertical radiators free up wall space. They also allow you many more room layout options. So, if you like to keep rearranging your room, this is the best option.

A vertical radiator has more design statement options than a horizontal one. This is as it is far more visible. In either a vertical or horizontal option, modern design keys are there allowing you to make a statement. Be that low-key slick modern, or Barbie meets steam-punk.

A horizontal radiator is the traditional norm that people expect. It is the magnolia paint choice. So if you are renovating to sell a traditional semi-detached, match most people's expectations with the horizontal choice.