Underfloor Heating - all over or just ground floor?

[quack13]

I'm about to start a new build and intend on putting in a UFH system (geothermal) with HRV and hopefully have an airtight build too.

I had initially intended to get the Underfloor Heating on both the ground floor and first floor, however a few people have suggested to me that I should consider only getting it on ground floor and get Rads put in upstairs.

Reason being that we would not be upstairs all the time, save for going to bed and bathroom, and that a quick blast of heat from rads would suffice.
I'm wondering with HRV, good insulation, concrete 1st floor and UFH downstairs would this work?

Has anyone here any experience on this?
Would be curious to hear peoples opinion.

 

[Marto]

have received similar advice to this. UFH is most efficient if left on (thermostatically controlled) all the time.
What is the point of having it so in your bedrooms if you are only in them during the night time (and usually very snug under a quilt at that!)

 

[jmrc]

I have UFH both up and down stairs. Mines a dormer, standard block build, 9x2 joist, 3/4" ply on top and the pipes for upstairs laid on this with a 40mm scread pumped in.
Living in the house now 3 years. No rads upstairs is great. So easy to plan any room, when space is at a premium it certianly makes life easy. All rooms on stats and are mostly turned off in the rooms not being used. Because of the light scread it heat up in a couple of hours. Really nice when you step out of the shower/bath to a cosy floor.