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How To Choose Your Radiators

If you don't know by now, you should know that I'm a total sucker for column rads, and I would always recommend considering replacing existing radiators in your home when redecorating to column rads if you can. They fit perfectly into any scheme whether you’re going for modern, traditional, transitional, or any other interior style. You can customise them to be with or without feet, and add a custom colour too. Erghhh just so sexy.

With that being said, radiators are heat sources, so you need to make sure that you get the right size radiator to give you the correct amount of heat output for the room it’s going in. You also need to think about energy efficiency! If it’s too big, it will add to your energy bills, if it’s too small, you’ll be cold and have it running on maximum!

To make the process a bit easier, I wanted to pull together a step-by-step guide for you because there are a few things you need to do before you order your rads.

I've actually been shopping around to find the right radiators for the #asihome, and I've made a decision to go with the Cast Iron Radiator Centre. For what I want, they are able to give me the best price, and I know that they're a really great quality product too. I've also listed a few other places you can find beautiful rads too.

Follow these steps when buying your radiators:

Step 1: Measurements

Measure the room that the radiator(s) is going in. You want to note the width, height, and length.

Step 2: Find out your BTU (British Thermal Units)

This will determine the BTU output your radiator needs to have. To work it out, you just use a BTU calculator. You can either type ‘BTU calculator’ into Google, or head to Cast Iron Radiator Centre and use their one. I like this one because it asks you a few more questions to get it right, like whether you have double glazing in the room, where the radiator will be placed etc. The more questions, the more chance of getting it right and helping with those energy bills!

Step 3: How many do you need?

Write down how many rads you need in the room, and note down whether they’re going under a window or if they need to be a particular height. I'd also recommend having a browse on Pinterest for inspiration because you might decide that in some rooms you'd like a short rad, whereas in others the design might lean towards a standard size. My Pinterest has also got loads of inspiration on there.

Step 3: Choose your rad

My favourite is the four-column traditional radiators, but take a look around and find the right one for you. The more columns you have, the more depth you'll need to allow for. If you've got a particularly skinny hallway, for example, you might want to consider a 2-column rad. Or, if you have a large home and want to build a sense of cosiness, or add a sense of grandeur, then you may want to go for even more columns for example you could go for various heights of a 9-column rad like this one:

Cast Iron Radiator Centre:  Traditional Victorian 9 Column 330mm Cast Iron Radiator

You'll also need to get an idea of how many sections you want to aim for. You may need to be flexible with the sections though, as you may need to add/decrease these depending on what BTU output it will give you. Also, if your plumbing is already in place and it's not being moved, you'll be restricted to use the existing width.

Our plumbing was generally ok and mostly in the right places, but design-wise, I didn't want the new radiators to be as long as the existing 70s radiators. Before altering our plumbing, I checked that we would still maintain the right BTU if the width was reduced - and it wouldn't. So, the plumbing stayed put and I've had to compromise with longer radiators. These are just little things to think about, so that's why it's always best to have your interior designer on board from the beginning if you are using one, and if not, having a strong idea of your design direction is really rather important.

What are columns and sections?

The columns are what you see from the side profile, so for example these radiators have 4 columns.

Cast Iron Radiator with numbered columns


The sections go across the length, so for example, this radiator has 14 sections.

Cast Iron Radiator with numbered sections

Once you’ve got an idea of the height of your radiator and how many columns and sections you want, choose the style of radiator you want (I like the traditional ones), and then select the closest height to what you're looking for.

Then, open up the list of options and look for your desired width and BTU. If you’re having more than one rad per room, you can split your BTU between the radiators so it covers the room. Sometimes the option for the rad you want is right there, sometimes you need to compromise on adding/removing sections or changing the height to get it right. (Just like I did for our living room. I didn't want more than 14 sections design-wise, but I've had to keep them at around 16 sections each because otherwise I'd of been under by about 2000 BTUs and they wouldn't heat the room effectively).

List of radiator sizes and BTUs on Cast Iron Radiator Centre website

Step 4: Pick your valves

I personally love an antique brass valve with a wooden twist top. We are going for thermostatic valves so that we have more control over our heating. Here's a few that I love.

Step 5: Decide if you want feet

Yes, I did say feet. Some radiators attach to the wall, and some sit on radiator feet and attach to the wall with wall stays. Rads with feet and wall stays are personally my favourite. Rads with feet make me feel grounded, ones without feet don’t give me the same satisfaction. You can also add decorative feet if your rad doesn't have them already.

Here's an example of rads with feet:

And here's one without feet:

Milano Windsor - Horizontal Traditional Column Radiator - Triple Column

Step 6: Pick your wall stays:

I think wall stays add such a classy touch to your radiators, isn’t it satisfying when functionality and form intersect with absolute beauty? I like to match these with the hardware in your valves, so go for a gold/brass mix or stay with chrome/nickel.

Step 7: Pick your finish!

Don’t forget to think about the colour and finish. The colour of your rad has everything to do with the overall vibe and feeling in your home so don’t overlook this decision. It’s one that has held me off purchasing ours yet because I need to make a final decision on the colour schemes in the house.

You can also pick between a satin finish, matte finish etc. Most companies will give you a standard set of finishes and colours plus some additional custom colours like bronze for example which can be realllllly sexy. Some companies also give you the option to customise with a specific paint colour so you could choose from a RAL or Farrow and Ball colour for example.

Some additional tips

1. Budget for delivery costs

It usually makes sense to purchase all your rads for your home in one go as the delivery fees can be extremely high. Just check, double-check, and triple-check it before you hit purchase, and make sure you’ve got yourself covered with refund terms and conditions in case you do mix up some of the measurements and you can easily replace it.

2. Don't risk it, know your end goal

This is one of those things that can make renovating and redecorating a challenge. Knowing what your overall design is going to look like before you get started on your project is so important. Not having this can affect more things than are often realised, and without a design direction, your progress can come to an abrupt halt. Don't risk it and get any old radiator and hope for the best. My advice is to have at least nailed your design direction before you invest in new rads, especially if you're going for custom colours.

3. Be prepared for your plumber

Your plumber will need to know the placement and width of your chosen radiators before they get started. Especially if you're planning on moving the location of your rads, this is helpful for them to know so they can give you an accurate quote. If you haven't got this nailed before they come - it could be a very short meeting.

Shop for your rads

A quick Google Search and here's some places you can have a look at. I haven't purchased from them so make sure you do your research first - read the reviews etc! I'll be going with Cast Iron Radiator Center.

There you have it. All the advice I can give you! Happy shopping, and let me know if you found it helpful.


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