Have you considered geothermal?

See link below.

SR

Here is a link that might be useful: Nordic Triple Function Geothermal Heat Pump

Will this house have AC? How are you going to heat the rest of the house and basement? What type of flooring will the be on the first floor?

Where are you located? Is natural gas available?

I am curious as to why want to use radiant heat on the first floor and if have you considered other options.

Thanks for the reply so far. I should have been more clear on some details.
The whole house will be heated with radiant floor heat over hardwood, including the basement and upper floor. We will be using a natural gas condensing boiler (I believe Viessmann)
We are in Vancouver, Canada so mostly heating days and no AC.

Our concern is basically will the 2 zone be effective in an open floor plan. If one zone is turned off and other is on, will the heat spread over to the off zone and making it effectively just one big zone with half of the zone turned off.

Yes maybe, but with hot and cool spots

Exactly why you need an expert that will consider and factor in all the variables........losses.....gains......insulation......climate.....

Examples
Heat rises
Window solar gain or loss
Materials
Ceiling height
Attic space and insulation
Wall insulation
Square footage for each room, cubic footage too
Temperature of water...loss per run

Based on my experience, I'd say that trying to divide an open area into two zones won't work.

We built a 1000 sq ft addition of several rooms and and an open area - it has its own furnace and a new furnace was put into the existing structure at the same time. The connection between the areas is a wide-ish hallway. When both furnaces are on, the house is evenly warm. Without closing doors, it's not feasible to have the heat on on one side but not the other because the cold air mass on the "off" side keeps the "On" part of the house from warming up. The areas most distant from the border will get too warm as the system tries to compensate, and the areas near the border stay cold.

Neither cold nor warm stays put because you want it to. In your plan, I think there would be a constant flow of warm air to the cold area along the ceiling and cold air to the warm area along the floor.

Not a question that you asked, but your plan suggests you're going to have a very dark region by the dining room and stairs. You've got a long wall with no windows between the living room and the family room, and the fireplace will block light coming from the front.

Good luck