Replies

1. 
   RBean | Jan 10, 2005 06:23am | #1

   Suggest you contact the folks at Uponor Wirsbo - they have some insulated PEX stuff made specifically for your application.

   Its called ecoflex...contact info is at:

   http://www.wirsbo.com

   RB

    

   
   

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   Edited 1/9/2005 10:25 pm ET by RB

1. 
   dgalas | Jan 10, 2005 06:42am | #2

   Perfect! Thanks so much. It's amazing how much easier it is to find info on the web when you have a NAME for it!-Dave

2. 
   globaldiver | Jan 11, 2005 10:28am | #3

   Dave: 

   I'm thinking of a similar thing for my Boise shop, but running from the shop to a greenhouse.  I had been planning on taking the two loops of pex, suspending them in the middle of a 3 inch or so pvc pipe (probably have to drill some holes and insert wire to hang the pex in the middle) and then fill the whole thing full of the expando foam.....

   But it depends on what Wirsbo wants for their stuff, I suppose.....

   --Ken

1. 
   IdahoDon | Jan 11, 2005 10:57am | #4

   Using Takagi tankless hot water heaters we've built some very effective systems back in Wyoming that are relatively simple and cost effective.  I'm now living in Boise and can't figure out why more people here aren't using hydronic heat.  It probably has to do with the need for air conditioning and the ductwork required for that since the floor heat is somewhat redundant.  Heck, I even miss working in houses that have radiant floor heat since it eliminates much of the drafts and cold spots in houses.  We would really enjoy sitting on a nice warm concrete slab to eat lunch in a half finished house.

   Remember the key to heating system effecency is to eliminate the need for heat in the first place and insulate, insulate, insulate.

   Cheers,

   Don

   PS  For small hydronic loops away from the house you might be interested in using standard hot water heaters as a heat source.  Very low cost and easy to set up.  With the hot water heater set to a low temperature you avoid the need for hot/cold mixing valves and the related tubing. 

3. 
   johnnyd | Jan 11, 2005 04:57pm | #5

   Big question to deal with here IMHO is:

   Is it really worth the extra research, digging, etc to try to use the same set-up for both house and shop?  The plumbing part...pumps, near boiler piping, manfolds, controls, etc.  are really pretty simple (especially when what they need to do is kept simple) and do not account for a huge percentage of the cost of a radiant floor system.

   YMMV (your mileage may vary), but I think it would be worth your time to compare the materials, labor, and subbing costs between a combined system and two separate systems...because your shop will probably have very different requirements than your house and you may have to either make compromises on the comfort of both areas, while at the same time unecessarily increasing the complexity (and expense) of your heat source and control tactics.

   One way I can see this being worth it would be, say, if you had a big outdoor wood fired boiler a really stable cold winter (6000+ HDD), and a good cheap wood supply, I could see alot of efficiency in piping that hot fluid to multiple heat loads.  Just go out and load that baby up once or twice a day and let your controls handle the rest.

   Something I may look into, as I have multiple loads with separate systems in the middle of the woods in SE MN.

4. 
   csnow | Jan 12, 2005 06:23pm | #6

   "Can I run a couple of PEX loops out to the shop, buried and insulated, and avoid having to set up two separate systems?"

   Sure, though you would almost certainly want a separate zone.   How cold is your climate?  Do you want to have to run it all the time to prevent freezing?  What if the power goes out?  Might want to consider running that zone with a glycol loop through a heat exchanger.

   Lastly, is RFH really the best choice for the shop building?  How often are you out there?  RFH is slow to warm up, so you would have to keep it warm all the time.

1. 
   timkline | Jan 12, 2005 08:08pm | #7

   Lastly, is RFH really the best choice for the shop building?  How often are you out there?  RFH is slow to warm up, so you would have to keep it warm all the time.

    

   I was thinking the same thing, mainly because the slab is there already and the tubing should have a couple of inches of foam insul underneath. 

    carpenter in transition

1. 
   dgalas | Jan 12, 2005 08:30pm | #8

   Our climate is pretty mild. We only get snow about 1 week out of the year and don't really have to worry too much about deep frost.
   I'm out in the shop almost allday everyday, so the efficency of RFH I think would be worth the slow heat-up. I will certainly keep the shop on a separate zone though.
   The one thing that has me a bit worried now though is the fact that it looks like Ecoflex comes with PEX pre-installed only down to a diameter of 1". I certainly wasn't planning on running 1" tubing for the RFH! Can the tubing be successfully stepped-down to 1/2" someway?Thanks for the feedback so far!-Dave

1. 
   csnow | Jan 12, 2005 10:52pm | #9

   "The one thing that has me a bit worried now though is the fact that it looks like Ecoflex comes with PEX pre-installed only down to a diameter of 1". I certainly wasn't planning on running 1" tubing for the RFH! Can the tubing be successfully stepped-down to 1/2" someway?"

   Sure you can.  If you can't find a PEX to PEX reducer in that size, you can always improvise with copper in between.  The idea with the large sizes is that this stuff is generally run to supply a larger outbuilding, possibly a long distance away, so they would typically need to move enough volume to supply multiple loops off a remote manifold.

5. 
   ronaldrady | Jan 12, 2005 11:33pm | #10

   I love RFH. As someone else suggested, use a hot water heater. I have seen 1500 sf homes heated efficiently with a hot water heater.

   Another option that is done here very often is urethane spray foam. Run your tubing in a trench and have it sprayed with urethane foam. Use the aluminum reflectors to keep the heat from radiating down into the concrete.   

6. 
   frenchy | Jan 13, 2005 12:50am | #11

   Wirsbo won't sell to do-it-yourselfers.  call radiantex     instead..

    second consider using a water heater instaed of a boiler..

     First it's much less expensive,

        second it's far more efficent* 

           third you can use a second water heater as back-up..

     * boilers run at 195 and then the water needs to be cooled to go into the floor..Kinda dumb. over heat the water and then cool it?

     You can set the water heater to operate at whatever tempurature you need.   Water heaters operate at 105 or 110 and use much less fuel.

1. 
   rich1 | Jan 13, 2005 07:59am | #12

   Water heaters are about 40% compared to a cast boiler at 80%  or a condensing boiler at 95%.

   Cast boilers need to be 140 minimum, condensing, the colder return the better.