Radiator Calculator - How Many Do You Need?

By Author: Edward Hall
Total Articles: 93
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Is there any one way to calculate how many radiators you need? Is it possible to find a good online radiator calculator to either check how many you need to buy, so you can source your cast iron pieces, or check the recommendations of your designer?

The basics

One of the basics of radiator calculations is to be sure that your house is fully heated without needing to keep your heating on full blast - one of the funniest outlooks I heard from a friend was that if you've got a smaller amount of radiators, you can lower your heating bill - conversely, with less radiators, the reality is you'll probably have to run them longer to keep your house warm, so this probably isn't true. Having enough radiators will also ensure that you can seal off rooms and keep the heat encapsulated.

You should consider having one radiator, large or small, based on the room size, per room - larger rooms may need two large radiators, or walls that are long and narrow may fit two smaller radiators - it really depends on the layout of your rooms and house.

Combi versus back boilers

Most older houses are fitted with back ...
... boilers - which aren't as cost effective as combi-boilers. These ‘always on' heating systems cost far less to run than back boilers - so you should also include aspects of this in your radiator design choice - if you're fitting older style cast iron heating systems to a back boiler, they may cost much more to run than off a combi boiler. For that reason, you may find that fitting your boiler with your radiators and let you upgrade your heating system at the same time.

More advanced problems

One of the biggest reasons you'll need more radiators is poor insulation, or heat loss - one of the best ways to ensure that your radiators work well is to ensure that all of your insulation is up to date, and make sure that your home is fully insulated and designed well. Closing doors and making sure that your house is used correctly is another important step - if your windows aren't double glazed that's another important step to ensuring your house is heat proofed to the best of your ability?

Radiators can also have several attachments fitted to them, from simple silver sheets at the back of them, where it reflects the heat up and away from the walls. You can also get fans that sucks up air and blows it out into the room, instead of dispersing it backwards, as well as in front of the radiator, but these sometimes are less than cost effective because they don't work as advertised and need fitted to your systems.

With many years in the heating and plumbing industry Edward Hall has for sometime now been writing on such subjects as the cast iron radiator , its history and benefits and imparting his vast knowledge on the subject.