Radiator size calculator

[martyc]

Hi Guys,
Is there such a thing???...want to put rads into my garage...its 24 foot long by ten foot wide...ceiling is vaulted 8 foot at one side ~13 foot the other side...so an average height of 10.5 foot...i havent insulated this yet but will be putting 200mm of rockwool similar up there.

Heat source is gas boiler that currently serves the house.

Ideally id like 2 rads, this way if i ever split the garage into 2 rooms the plumbing will then lend itself to this.(people in ireland have a tendency to convert garages into extra bedrooms...i wont be doing this but if im selling the house down the road....)

Also garage walls are insulated with kingspan foilbacked board...garage door is also of the insulated variety...only thing that isnt insulated is the floor.

Just looking for a guestimate sizing for 2 rads that should heat this space.
Thanks,
Marty.

 

[Biggles..]

width(feet) x length(feet) x 36 = btu's, shouldnt see you far wrong.

 

[D_Hailsham]

You can download a free heatloss calculator from

http://www.quinn-radiators.co.uk/downloads_heatloss.php

This will give you a more accurate figure

There is also a downloadable manual on the same site.

Don't forget that how you split the heating load between the two radiators will determine how you could divide the garage into two rooms in the future.

 

[holty]

try http://www.heatweb.com/ then select flash tools. theres a good one on there.

 

[chrishutt]

So no windows in the garage? It sounds like it's going to be very well insulated. Losses through the floor will depend on how much of the perimeter of the floor is to the outside and how much against the house.

Heat losses should be very low, well under 1 kW for each room. Probably not worth spending too much time working it out exactly. Just buy a couple of 1 kW rads and fit TRVs so that the output won't be excessive.

 

[gas4you]

2 outside walls = 2950 watts approx

3 outside walls = 3650 watts approx

Split these figures between the 2 rads how you like.

 

[martyc]

Cheers Guys...yeah no windows but 2 small Velux.
It has a big garage door either end both are insulated and are 9 foot wide by 7 each!
Ill have a look @ rads based on the figures you guys supplied here and see if I can pick up something handy with TRV's...if i do put in 2 rads they will probably be equal size.
Cheers,
Marty

 

[Malc C]

Ok I'm lost !

Using the heat loss application from http://www.heatweb.com/ does that mean that if, for arguments sake, the calculated loss for a room is 10000 btu that you need to install rads to that value to maintain the required temperature (say 21c for example).

Cheers

Malcolm

 

[gas4you]

Yes

 

[Malc C]

Dave, straight and to the point - Thanks