Radiator sizing calculator

YorkshireBoy

Morning all.

I'm about to put central heating in a property (but will have the actual boiler fitted and commissioned by a professional!) and I'm struggling to find a good online calculator to help me size the radiators.

Even the ones which seem to ask for comprehensive data, ie floor construction, north facing, wall construction, glazed area (sq m), what's above the room, etc, seem to differ greatly in BTU requirement.

I've also had 3 plumbers in for quotes for the boiler fit/commissioning, and they all suggested different radiator sizes (and hence BTU requirement).

Please can anyone point me in the direction of a reliable online radiator sizing calculator?

moonrakerz

YorkshireBoy wrote: »

Please can anyone point me in the direction of a reliable online radiator sizing calculator?

If you are getting so many varying results.

1. It must be a pretty inexact science to start with
2. How will you know when you have the "right" answer ?

DVardysShadow

Oversize by 20% to 30% and use thermostatic rad valves.The main requirement is that you don't end up with a rad which is too small. In the bad old days before thermostatic valves you had to be more accurate.

gas4you

Personally I never use online rad calculators and always stick to the industry standard Mears calculator.

However, if I was to ever use one, I would use the Stelrad Stars calculator, but it takes so long to do, it would not be cost efficient for me to do so.

YorkshireBoy

Thanks for the replies. I've downloaded the Stars calculator and I'm working throught it! Seems the most comprehensive one I've seen so far.