Installing in-floor heating from the top.

As mentioned in a post under the forced air section, I am taking possession of an old fixer upper house. The current setup is forced air gas on main (with electric baseboards still in place) and electric baseboard on second floor.

I am leaning towards going hot water heat as I loved the multi-zone controls I had at my previous house, and this one is just as big or bigger.
That being said, I'm looking at going hot water heat with in floor heating.
The previous owners installed super cheap laminate flooring with no underlay so it has to come up. My thoughts are, if the flooring is coming up, is it possible to pull the floor boards (plywood it looks like) and install in floor heating from the top, saving the drywall mess on the main floor?
Has anyone installed in floor heating from the top?

I have experience with boilers and slantfin systems, but not in floor heating.

 

I am not the expert here, so take everything I say with a big grain of salt.

I've installed electric radiant floor heat from above, under tile, without any problems; it works great and was easy. But that is quite different from what I think you have planned. The electric grid is very flat and the tile conducts heat well.

I have helped friends install radiant hot water heat under wood floors, but always from below. I don't see any reason why you won't be able to do it from above. You will want to insulate under it, and may have to raise the floor a bit.

My bigger concern might be how much heat you will get. You say the house is old, and you are in Canada. If it is drafty or poorly insulated, it may be hard to get enough heat from the floor to keep the house warm when it is really cold. You could use the elctric heat to supplement on cold days. Then you'll still have nice warm floors.

 

Lots of good information about hot water radiant heat here:
SupplyHouse.com - Plumbing, Heating & HVAC Supplies and
http://www.radiantec.com

Using
A5060701 - Uponor (Wirsbo) A5060701 - Quik Trak 7" x 48" Trak
I have installed radiant in two bathrooms--one tile and the other engineered wood flooring and they both work great. Make sure any wood floor you use on top of the radiant is approved for such use.

Make sure you heed the advice given in an earlier post about how much heating you will need. Even if you have to supplement the radiant with some baseboard, having the warm floor is really nice.

 

I found a similar product to those trak 7"x48" which was a tray that mounted to the top of the joist, which held the piping between the joist. I think the setup you have linked may be a better idea as it would replace the floor board I am going to be removing.

 

I think those trays are for installation from below. I'm not sure that the Quik-Trak is thick enough to act as the subfloor directly on top of the joists by itself. It is only 1/2 inch thick. You can mount it on top of the existing subfloor or you could replace the existing subfloor with 1/2 or 5/8 plywood and the Quik-Trak on top of that.

 

You may already know this, but if you're planning to have in floor radiant AND baseboard or radiators, they operate at different temps, and your system will have to accommodate that. Good luck, Steve