Underfloor heating?

[malcolm]

100mm concrete slab on suitable DPM ( may need Radon, ask building control) on 50 sand blinding on min 15o compact hardcore
100mm kingspan under or over floor slab, (I prefer over as easier with pipework install) with minimum 25mm perimeter insulation (under takes longer to heat up and slower to cool because of the greater mass)
get a kit for the pipework, polypipe and Nuheat will both design for you and supply a complete kit, usually in 50- 75mm sand cement screed

Good point it will need to be done to building regs. That probably rules out the idea as it's an old building and the foundations don't go 0.5m below floor level. The roof timbers are a bit low and there is a step up to the barn so I can't add 200mm on top of the existing either.

Sounds like the systems come with a mixer to cool the water down so can be plumbed into an existing boiler which is good news.

 

[MCKDAVID]

If you're struggling to balance heating across the room, and the floor at that end is not practical, what about ceiling radiant panels? not the most efficient, but they've come a long way. Might give you more options, depends on what ceiling space you have, i.e; fit in between the beams. They can be either wet or electrical.

 

[normspanners]

I havnt read all of this but as far as insulation goes how about this for an idea, around here now with older houses, the method is to insulate the outside by fastening dense polystyrene to the outside then rendering the polystyrene, sister in law has had it done and it works well, the idea is the walls heat up with your heating and store the heat inside also the house is quieter.

 

[mike os]

You could go with a low profile system... adds about 20 to 25mm to floor height. .. heat loss. into the slab will be higher but bo worse than heating the room any other way

 

[mike os]

Remind me and I will see if I can find details. .. iirc it's nuheat.co.uk

 

[malcolm]

I looked at the nuheat low profile system. Can't imagine building regs would allow me to fit it without insulating the floor (already insulating the walls, windows and roof as part of the change of use requirements).

Probably worth me chatting to the building regs guy next time he is over to see if there is a way he will let me to dig up and insulate the floor without undermining the foundations or underpinning and all that rubbish. Maybe taper the hardcore down from the walls to get the depth they want in the middle. I can probably go down 300mm at the walls.

 

[mike os]

Existing structure mate.. They can't make you change it, but if you replace it they can make you work to current regs