Home DIY

Underfloor heating questions...

I'm about the rip up the floorboards in my hallway and downstairs bathroom (which runs off the hallway), replace with a ply subfloor and fit a Karndean vinyl floor on top that runs through both.

There's a large radiator in the hall and a small towel one in the bathroom. I want to get rid of both in an ideal world, and replace with a wet UFH system.

Here are my questions:

1. Can I fit the UFH system to the existing rad pipes but regulates the temp so i don't burn my feet?
   
2. Are there any systems that integrate into the subfloor to keep the floor height as low as possible?
   
3. Will they work with the adhesive for the vinyl floor?
   
4. Am i mental?