Hello, I just bought a 130 year old house that is heated with an oil fired boiler (Commercial Grade Viessmann as this was used as a B&B before we bought it). The whole system is done in copper with floorboard radiators which my wife does not like the look. I'm currently taking up the floor and installing a subfloor as the house doesn't have one. Can I take out the baseboard units, solder a PEX transition on the end and then run PEX above the subfloor/under the hardwood? Also since everything is off, would cellulose between the joists be a good idea before I put the subfloor down? Thanks! Scott

No, these are very different heating systems. You would first have to accomplish a proper room-by-room heat loss analysis and then accomplish a proper hydronic radiant floor heating design if you truely want to go this route. You would be well advised to hire a contractor who has experience with this sort of heating system transformation and remodel.

Thanks sail. I know those recommendations from reading your other posts. I'm just wondering if my current piping to the rooms would be ok to use as far as getting the water from the boiler to the room or do I need to rerun the entire thing on pex. There really isn't anyone around me that does this sort of thing and all the hvac guys I've had by said it was no big deal but I thought I'd check here since there is a lot of experience on here.

No one else going to weigh in?

Sail, I was looking over your calculator page and I love the ballistic calculator. I've certainly contemplated adding an outdoor range, I just need to build up a berm. Maybe a skeet range with four heated tiles to stand on while I shoot barefoot in the snow. lol

Sorry for the terse initial response and the subsequent delay responding. I have been traveling in a remote area and my internet access has been limited to my cell phone and cell coverage. Anyhow, I am glad to hear that you found our ballistics calculators to be useful. I developed these for my son and his law enforcement friends who do extreme long distance shooting. I am more of 30-30 or 45-70 lever action gal myself!

We would need to know the details of your existing distribution plumbing to ascertain for certain whether it would be adequate for what you propose. Typically, one would use 3/4” to 1” diameter PEX to provide the supply and return distribution water to manifold(s) that would then provide the supply and return water to all the required circuits. Typically, one would use 1/2” diameter PEX for these circuits and use a 12” spacing. One should not exceed 300’ length per circuit (or hydraulic friction and associated pump head can become too large) and this implies about 300 square feet of floor area per circuit. The distribution plumbing is usually a small percentage of the cost of a hydronic radiant floor heating system, so you might just want to use PEX if routing it can be accomplished without too much pain. Again, you might be wise to try and find someone experienced with this sort of heating system remodel as there are many aspects that could trip you up.

http://www.blueridgecompany.com/radiant/hydronic/769/rht-6-inch-extruded-heat-transfer-plates

If there is unconditioned space below the floor, then you certainly want to insulate it.

I expect that you will have to do something to reduce the water temperature for the floor. Or, if you intend to keep the high temp, then you may want to use a radiator with reduced efficiency.

So Badger, would I rip 3/4" plywood to create channels and screw down to the subfloor and put those inbetween the ripped pieces with the pex and then include the end pieces that blueridge sells to make the bends?

Exactly.

This is the best value for the DIYer.

Blueridge knows how and has the whole package.

Oh man, I'm glad I found this place. So today I had a HVAC guy come and say that while I had the floor up the best thing to do would be to suspend a pipe between the joints (in the middle and not contact the subfloor), pack it really good with insulation, install the subfloor, and then the floor. Then the pipe would "heat up the insulation" and push the heat up.....

Hey guys, one more question in terms of "hardwood". My floor is pine which is technically "softwood" but I know most people still call it hardwood. Would the Pine still be ok to put on top?
Thanks!

Yes. Pine is fine.

I just ordered the Siegenthaler book that everyone recommends. I'll make sure to keep everyone up to date on the progress as I go along.

thesouth18

I tried to reply to your PM, but it wouldn't work. Please email me (got it)

Thanks