New to the site...hope I can get some feedback on my basement remodel in Minneapolis, MN area.

Would like to add radiant to the living room, but have no head room to loose.   That leaves me with the need to remove the slabe and re-pour.  Not a problem, as I have lots of connections in the contracting industry.

Problem is, the walls are finished with a fuax stone and half logs.   The wall sticks out over the existing slab, so I am concerned about damage to the walls.

Was thinking of the scenario below:  Cut the slab and leave 2 feet around the edges, install a thermal break (2" insulation) at the cut and pour a new slab in the middle with heat tubing 12" O.C. in it.   Trying to decide if I would dowel the new slab to the existing one or not..Probably won't make that determination till I pull out the old slab and see how the subgrade looks.   Everything is sand around me, so I am betting it will be a good foundation under it.

There will be a cold area around the perimeter of the room, but I am thinking the heat from the center slab would overcome it.

Any comments would be appreciated





 

one problem I see is this does not allow you to decouple from the existing footing and wall so the remaining existing slab would draw out more heat then if you could separate the entire floor slab from the footings and wall.

Depending on local conditions, the remaining existing slab could also be a condensate collectors as it will be the coolest point in the basement.

If you do it the way you have diagramed, use Trex or one of the other decking materials rather then wood so that if water does collect at that point at least you won't have rot.