rad sizing for a conservatory

[loafer]

There seem to be a plethora of websites that can size the optimum or minimum recommended output for sizing a radiator to a room.
Very useful indeed
They can even take into consideration...
room dimensions (both in cubic yards and metres) OH MY!
is the room double glazed
north facing?
do you have cavity wall insulation?
what is the floor covering
bedroom..living area... hallway?
do you like a warm comfee lets all get nekid and dance or
are you such a skinflint/energy conservation conscious person that you will tolerate a lower temperature and put an extra wooly jumper and hat on?
do you live in the channel islands or in the orkneys?

However, (here's the rub) How would you go about sizing a conservatory???

8.5 m's x 3.5 m's (ceiling averging 2.6m's) with a suspended wooden floor covered with laminate, with three external walls?????

Oh and the dwarf walls upon which the upvc is mounted will only take at max a 400mm high rad!??

 

[gas4you]

Firstly somewhere in the depths of the ridiculous building regs is a reg that does not allow rads in conservatory's over 30m2

I always size the conservatory as a normal room then add 50%.

Usually the brickwork that the glass frames is built on is 600m high so a 450mm rad will fit quite easily.

I always size my rads to enable the occupier to sit in their conservatory mis winter with snow outside, in T shirts if they must

 

[sturharv]

Exact way of doing this is; assuming no insulation in the floor and walls, and glass is double glazed

floor area in m2 x 100(watts)

so 8.5 x 3.5 x 100

2'975 watts OR 10'150BTu (size the rad based on this)

put a TRV on it

 

[simond]

So the height doesn't make any difference then?

Exact way my ar**

 

[Agile]

The plain fact is that a conservatory has a massive heat loss compared with a proper room.

Its not designed to be a habitable room.

The only thing you can do is put about 1 kW of heating per 5 m² and understand that it will still be too cold in very cold weather.

People look very odd sitting in a conservatory after dark to the neighbours! Its best to have a zone valve and turn it off when its not being used to conserve energy/heating costs.

Tony

 

[markplumb]

convection heaters work quite well i find, fast heatup time and good for air movement in the summer too when its too hot in there. They are a little bit more expensive but so much smaller than a wapping great big double 450mm rad.

 

[Agile]

Yes, they are a very good way to get a high heat output from a small unit.

Even better with the type used in cheap hotels with a runback timer so they go off 20 minutes after being put on.

The worst night in my life was in Scotland in a hotel room in a round turret with no insulation at all and -1 C outside and only two thin blankets. I could find no way to keep the electric heater on and ended up wearing my outdoor protection suit in the bed!

Tony

 

[sturharv]

So the height doesn't make any difference then?

Exact way my ar**

Well, this is the method I use for all Conservatory's, they do tend to all be 2.6m high anyway.

This guy wants a solution not paragraphs and paragraphs.....

Its on the 'top side' put a TRV on it, you can always turn it down

 

[Richard C]

We have an Edwardian, 25 m² floor area with 3.5m ceiling height. It has 50mm of Cellotex in the floor, cavity insulation in the dwarf walls, K glass & a 40mm poly roof; to size the heating, I used 200W per m², same as agile suggests but even this isn’t enough in the depths of winter. We also have a 3kW radiant heater we can use as a booster but it starts to get so expensive to heat in winter we now close it down November through February & de-camp to the lounge which has a lovely open fire where we burn free wood! If you really want to use it all year round without huge heating bills a cons of that size will involve, go for a Garden room with a tiled & insulated roof.

 

[Agile]

Its nice to find someone whose practical experience exactly confirms what I have advised on the forum.

Tony

 

[loafer]

Fantastic. Thanks for the suggestions folks! Much appreciated. Even more so I seem to have prompted such a good debate on the subject.