How many radiators?

[dcwuk]

Hi all
did a search but could not find the info.
my question is how many radiators would be recommended for a room 5m by 3.5m?
The room having one window and a pair of french doors.
The single radiator is located on the opposite wall to the window/door and is 1m long
cheers

 

[Softus]

There is no defined number - it comes down to the total rate of heat output for all radiators in the room, and the practicalities of size for each one.

For example, three 1m rads will emit heat at almost exactly the same rate as one 3m rad (of the same make and type).

To get this right you need to calculate the rate of heat loss for the room, and provide radiators whose output exceeds that rate of loss. The amount of excess determines how quickly the room will heat up from cold, but also how big your bills will be.

 

[dcwuk]

There is no defined number - it comes down to the total rate of heat output for all radiators in the room, and the practicalities of size for each one.

For example, three 1m rads will emit heat at almost exactly the same rate as one 3m rad (of the same make and type).

To get this right you need to calculate the rate of heat loss for the room, and provide radiators whose output exceeds that rate of loss. The amount of excess determines how quickly the room will heat up from cold, but also how big your bills will be.

Thank you for your reply, what are the calculations is this something i can work out?
Or is there a general rule of thumb?
regards
dcw

 

[Softus]

You should use a heat loss calculator - I still have a Mears calculator, but these days there is PC software and also web sites that do it. Google should reveal a few of them.

 

[dcwuk]

Thank you for the info will have a look again later but a quick calc tells me i need 5420 btu.

 

[leakydave]

or 1588 watts, or 1.59 kW... see what rad or rads fit best, and divide the total accordingly

 

[D_Hailsham]

To get this right you need to calculate the rate of heat loss for the room, and provide radiators whose output exceeds that rate of loss. The amount of excess determines how quickly the room will heat up from cold, but also how big your bills will be.

Why will the amount of excess affect how big the bill will be, i.e. the amount of gas used?