Hydronic Radiant heat on basement floor
I just read the aricle in FHB Jan/05 issue with great interest as I am in the process of finnishing a small portion of my basement and have been looking for a way to add radiant hydronic heat to my floors.
I have VERY limited head room in a hallway area as my main heating duckts are passing over-head. The rest is low but will work. Anyway, due to this I can’t build up to flooring too much (maybe 1.5″) so I was looking at some possible solutions.
Currently I’m looking at a product called Warmboard that is 1″1/8 thick and can take 1/2″ tubing. It’s the kind with the aluminum plates. On the manufacturers website they show two installation methods, sleapers and without. I’m trying to do the no sleapers due the the savings in height.
I should add that my basement is a walk-out and has been very dry since the house was built, 12 years ago. (I know, current performance is no guarantee for the future. Same as with the mutual fund market!) The final floor covering will be tile.
My questions are:
1 – Can I install this product (or any other similar) directly onto the concrete slab and still get enough heat going in the right direction (into the room) as opposed to into the slab and the dirt under my house? That is do I need to put some kind of insulation between the panel and the slab?
2 – As I’m planning to put the panel directly on the slab (if possible) making the floor pretty solid, can I put the tile directly on top of the Warmboard or do I need to put a 1/4″ of tile-backer first (loosing more height….)
3 – I have found a insulation foil that can be put onto concrete, it’s 5/16″ thick and has a R10 rating. If I need to insulate, is it possible to use strips of marine grade ply-wood, say 3/8 to make the sleapers, stick in the insualtion and then add the Warmboard panels? Will that make a strong enough floor to put tile on?
Any other ideas that might help or things I should consider are more than welcome!
Thanx for any help and have a happy new year.