How To Size A Radiator: 5 Steps

When choosing a new radiator for your home or workplace, there are various factors that you should consider prior to installation.

Whether it is a vertical radiator, convector radiators, designer radiator or any other model of heating appliance, the rules to follow generally stay the same.

Follow the next steps, and you should have your new radiator up and running in no time at all.

Step 1: Measure Your Available Space

This is the first and most important step you should take. There is nothing worse than getting a brand-new heating appliance that ends up inappropriate for the space you desire to fit it within.

Make sure that your room has adequate space before buying your new heating appliance and save yourself hassle further down the line.

Step 2: Measure the Radiator Height

If you are concerned your new radiator will be too tall for your environment, this step will prove to be one of the most important. Measuring the radiator height is a simple process.

Using either a tape measure or an app on your phone, measure the lowest point of your radiator to the highest and ensure it will fit into the desired location.

Step 3: Measure Radiator Width

Once more, this process is as simple as the previous one. To calculate the width of your current or new radiator, take your tape measure or digital alternative and measure across the furthest point of each side of your radiator.

Step 4: Measure the Pipe Centres

“Radiator pipe centres” refers to the distance between the two pipe inlets on your radiator. To measure this, take a tape measure from the centre of one of the pipes to the centre of the other.

This is done by measuring the centre of the right-hand pipe inlet to the left, again, a very simple process.


Step 5: Measure the Wall to Pipe Centres

This indicates how far away from the wall the pipe inlets of your radiator are at the point they enter the radiator valves. To adequately take this measurement, measure from the centre of the pipe inlet to the wall.

In doing so, you will be able to determine how far away from the wall your pipework is situated at. The benefit here, is that you will be able to determine whether you should or should not alter or replace any plumbing when replacing or reinstalling a radiator.

Measuring the wall distance is also useful and can be incorporated into this process, which is simply the distance of the back of your radiator to the wall.

By following these steps, you should be able to size up your new radiator and the location it is to be installed within, with ease. Many websites include a radiator size calculator, which does all the hard work for you.

Additionally, using a BTU heat loss calculator will assist with your decision as you will be able to determine the size and power of radiator that is most suitable for your environment.