Radiator BTUs and a large room - help!

[Misty9]

I've got a large living room - 4mx6.3m - which also has a double glazed large window (3m2) and a large double glazed patio door (3.3m2). I replaced the one small radiator with a large column one last year, which has a btu of 4700, but it was so cold last winter that I had to resort to using an electric standalone heater thing most the season

So this year I'm looking to install another rad at the other end of the room (external wall) but have worked out the btu needed for my size of space and it should have been covered by the one I bought last year?! I don't understand... The second rad will be at the diagonally opposite end of the room to the existing one. The room only ever had one rad it seems, plus an awful gas fire which I've has disconnected.

So, a rad of 4200 BTUs will suffice for the second one won't it? I don't want to fork out for another one just to freeze to death again this winter! Flooring is an old carpet on concrete base.

I'm looking at this www.bestheating.com/milano-capri-anthracite-flat-panel-vertical-designer-radiator-various-sizes-92541 and got the Windsor last time

Have you tried the online radiator BTU calculators? To be honest that one rad doesn't sound like it's enough. For example for my living room, which is 6x5m in a L shape, 2 large windows, 2 external insulated cavity walls, suspended wooden floor (however it has been very well insulated), plus a heated room above and I have 2 vertical double radiators which have a combined BTU of about 12500. That might be overkill but the room is very warm in winter with only the boiler on about half power. So yes I would say you definitely need more BTU but it really depends on lots of factors such as how well the room is insulated and external walls etc. Hope this helps

Hi, yes I did the calculator and it gave me an output of about 5000 for the space. Solid brick walls, concrete floor and heated rooms above. If I have two rads it'll be about 10,000 so I reckon that'll do it. There's just too much choice!

Yes I found it difficult to choose what to get when I chose mine. I ended up using 3 or 4 different online calculators as they all say something different and going with the highest one. I would rather have too much than not enough.