Vaulted Room Heating

[nirish]

We are having our double garage converted into a vaulted ceiling living room, my limited knowledge and more extensive research has led me to believe underfloor heating would be much more suitable than radiators.

The idea being convection heating from radiators rises and ends up above heat height, whereas radiation from underfloor generally stays lower and heats the objects and people in contact with the floor.

Am I thinking along the right lines?
Also would this underfloor heating simply connect to my existing central heating system?

 

[Madrab]

Certainly as far as the way underfloor transfers heat into the room but heat will always rise so will alway be warmer at the ceiling regardless of the room shape. UFH is a more constant overall type of space heating and heats from the floor mass evenly up into the room whereas radiators are convection heating therefore do work best with a more traditional room shape where air can circulate easier.

 

[HERTS P&D]

Stick a ceiling fan up and push the hot air back down again.

Andy

 

[nirish]

Thanks for the replies, I completely understand the practicality of a ceiling fan but it isn't the finish we want. There will also be two velux, one dormer and two hanging lights ...... so the ceiling will be well utilised already!

If nothing else the radiant heat across the entire floor should be preferable to hot spots at radiators drifting upwards before spreading across the room.

I'm also looking to upgrade my boiler, do I need to make any special considerations for adding a underfloor heating system?

 

[blubs]

nirish you clearly know your stuff, I also agree with both comments, underfloor heating is different to rads in that 19deg actually feels like 20 or 21 because of the radiant heat from entire floor (think bonfire night, cold temp but fire makes it feel warm), in this respect your right to think its better for a high ceiling.. , the big negative with UFH is the space, expense, noise and extra maintenance caused by the pump and manifold, (but you do get to have it as a separate zone with its own time/temp schedule), and if you need also to disturb floor to install it, i would just bite the bullet and put a couple of nice radiators in there, or 1 big one, the heat doesnt get 'stuck' up high, it goes in a circle, the warmest place to sit (apart from right in front of a rad), is the opposite wall where the heat comes back down !!, its worth remembering that there is no reason not to install underfloor heating system in a wall or two.. radiant heat will go in any direction..

 

[blubs]

as long as no one is gonna screw into them of course!!!

 

[blubs]

oh, and any boiler will do, as long as you have the extra kw needed, (about 2-3 i would guess), unless you have a big house and a 15kw boiler youll no doubt be fine, most boilers are criminally over sized, i never understand why average houses have 24 kw boilers (non combi), most rads are 1kw, 3kw for cylinder,( which isnt really needed, for example viessman boilers will only do heating or hw and no one ever notices that heating has gone off for 20 mins or so..) who knows of an average house with 21 rads!?? if you have a combi they start at 24kw, so youll be fine unless you have a 24kw combi and a massive house!! if any plumber talks BTU instead of KW, please ridicule him, that nonsense should have been banned in 1971

 

[nirish]

I definitely don't feel like I know my stuff, google is my friend and anything I know is sourced there. As it's a garage conversion there is no issue with disturbing an existing floor, it actually needs raised significantly to match the property. I'm worried in a 5m x 5m vaulted room that it won't feel cosy with rads. I admit my knowledge of underfloor noise and running costs are currently non existent.

As for the boiler, I'm not sure what we currently have but the house does have 19 rads. It's a Regular boiler with two tanks in the loft, I'd be interested in switching to a System boiler to free up space in case we convert the loft in the future, but I have no idea if the existing setup in a 90s property would cope with the pressurisation!

 

[Madrab]

It's a Regular boiler with two tanks in the loft, I'd be interested in switching to a System boiler to free up space

What you have, if you have a small cold water tank in the loft, is an open vented system. If you also have a hot water cylinder fed from a larger cold water tank in he loft then you have vented gravity hot water.

You don't need to change the boiler, just need to check that it can be used with a sealed system and then it's just a case of adding an expansion vessel with an integrated pressure relief valve/fill loop and seal it. If you do want to go sealed then it would be advised to pressure test the CH system first to ensure it can take the pressure. To get rid of the larger cold water tank, if you have one, then you need to change to a combi/unvented HW system.

 

[blubs]

most systems are fine when pressurised, a very old boiler without overheat thermostat should not be pressurised.. your garage should be fine if you have insulated it reasonably, as for boiler, if its 24kw or more i am sure it can cope with another 5kw over your existing 19 kw/rads, if in doubt put more pipes in the UFH system, they are v cheap.. one thing to consider, if you want to heat the garage at short notice, rads will be quicker than UFH ..a fan blowing across a radiator is even faster, you can turn it of when you get in there to enjoy the heat...