BTU for Bathroom

[sg1009]

Since this group is so helpful I thought I'd ask the opinion on what BTU to aim for in my bathroom. Using the B&Q calculator with the following data:
Room dims 7 x 9 x 8 ft.
North facing (two external walls and two solid brick internal).
Two small double glazed windows.
The calc churns out that I need

2646 BTU (B&Q use the Delta 50T I think)

I notice from other posts that people are recommending to go higher than B&Q calc. I am debating between these two:
500x1000, 1367 BTU two off making it 2734BTU total
or
600x1200, 1590 BTU two off making a total 3180BTU total.

I think of towel rads being covered by towels (shock horror) so that's going to be some surface area that's not radiating too well so I think either should do the job but 3180 seems rather excessive?

Any thoughts?

 

[2face]

always go bigger and the thermostatic valve will sort it if over sized .

 

[gas4you]

if your walls are not cavity insulated then my Mears calculator (10a) gives this as 4000btu. if you have cavity insulation then this would be 3100btu.

if you had given metric sizes then I could have calculated with newer calculator.

Never trust anything to do with B&Q

 

[sg1009]

Jeepers! 4000! That would be a towel radiator wall then.

Back to the drawing board.

Exact metric dimensions if you don't mind trying again (no cavity insulation):
208 x 269 x 240

http://www.radcalcs.com/ makes it just over 3000.

 

[gas4you]

Metric is 1050 watts = 3583btu for room temp of standard 22C for bathroom

 

[sg1009]

Thanks gas4you. Very helpful.

Is is normal to have a towel rad and a standard (500 x 600 double ish) rad then? One to heat the room and the other for the towel!

I can't recall seeing a mix of rads anywhere.

Pondering options.....

 

[gas4you]

Its up to you and what you think is visually acceptable?

A Stelrad curved white ladder towel rail 1800 x 600 will give 3489btu but dont forget that any towels on it will 'insulate' it

Chrome towel rails give out less heat for the same size

 

[TheBigMatt]

[quote="gas4you"[

Chrome towel rails give out less heat for the same size [/quote]



That explains a lot!!!!!!!!!!

 

[gas4you]

Just letting him know that if he doesn't like white then not to expect the same heat from a chrome towel rail the same size

 

[TheBigMatt]

LOL..... no, i mean it explains a lot in MY bathroom.......

I should have fitted a bigger chrome one or gone with white...still it looks nice...


Matt

 

[gas4you]

Unfortunately people generally think 'that looks a nice towel rail' and assume wrongly that it will heat the bathroom without calculating the heat requirements