Your Input Requested!

PhotoGuy

Before I start out - YES, I know that I need a Heat Loss calculation, etc. Trust me, that will all be done and I will have someone figure out a system that will work based on where the install will be, etc. I do plan on making my own above slab installs to save money. I have the time and willing to do the work. I can't believe the cost of Warmboard, Climate Panels, etc. (I just can't afford - or don't want to - afford this stuff.) I have the time and talent to do this part myself. I know my limitations and will only be doing this part and work with a pro I know for the rest. I'm down to two ways of doing this:

1) A panel like "Heatply" I can do very easily. I got a buddy that has access to a CNC machine and this would be no problem putting them together. Not much of a history on these from what I can find online. No real likes/dislikes that I can find other than on their site (all likes on their site). No aluminum involved, the pex would be spaced at 6" based on there pattern. Sure, aluminum would spread the heat better, but I'm thinking 6" is also pretty close and maybe makes up for the difference (no aluminum transfer plates). 3/8" pex, this would be using 5/8" ply.

2) Make my own "Uponor Quik Trak" or "Viega Climate Panel" type sandwich. Again, use CNC here for the ends but then just rip ply for the straights. I would lay down aluminum flashing and then just put boards above. Obviously, they would be spaced so the pex fits nice and snug like the real panels do. I would also do the 1/8th" 100% silicone bead for thermal contact to the aluminum. 5/8" pex, this would be using 1/2" ply.

#1 advantage is I get cost way down with no aluminum but I have no real idea if this stuff works in real world. I'm guessing it does or they wouldn't be selling it after a few years. Also, less DIY work than option #2. This option would require only 1/2" ply.

#2 has advantage that it is a known product. Not sure if I would have problems with aluminum making any noise as it isn't glued to the back of the plywood. I wouldn't think I would as these would be flat (unlike pex transfer plates). A bit more work and cost than option #1 but willing to do it.

Thanks for any input (and not asking "Why not just buy ....")

Ironman

The problems that I see are:
1. You're diving into the middle of the design process and not starting at the begining. The load calc is the begining. It's the foundation for the entire design. How do you know how many btu's youll need, what size tubing, it's spacing, what water temps, flow rates, etc.?
2. The other problem is how do you know what the btu output of your home made panels will be. Manufactured panels have specific numbers that have been calculated through extensive testing. The aluminum panels will always have a higher output than ones just made of plywood. Aluminum is an excellent heat conductor, wood is an insulator.

There's a common misconception about radiant heat that most folks seem to have: namely, that the heat is supposed to radiate from the tubing to the floor and somehow it will pass through the floor to the space that it's supposed to condition. That's not how a properly designed radiant system works. The tubing needs to be in direct contact with a good conductor (aluminum) which will transfer the heat to the wood, which will then radiate the heat to the space once the temp of the wood is above that of the structure and its contents. Just putting tubing against the wood leaves a very then strip of the pipe in contact with the wood which means there's minimal conduction.

They say a picture is worth a thousand words. If you wanna see how true that is, just find an image online taken by an infrared camera of a floor with plates and one without. No more words will be needed.

Gordy

Ditto. Ironman

Rich_49

Photo Guy
Even the most terrible products have market share , hell we continue to see them year after year on the site . Lathing , routing and adhering , Oh My. Aluminum is a great heat transfer but as I found out a couple years ago there are actually materials that are similarly conductive but spread heat more evenly , Graphite . We use this product here and have now in several homes where the customers love it , the average temps between tubes is less than competing products and is responsive as hell . Quiet as you want with none of the sealants , ticking , expansion noise and is reasonably priced . Check it out here , http://mechanical-hub.com/langans . Warmboard is a fine 12" on center product , the best in fact . But at 8" this allows lower water temps and is just as desirable . Did I mention that Warmboard has thermographic simulations of their product next to damn near everything under the sun . See if you can find a SunBoard comparison and ask why they don't have it , unless something ahs changed in the last few months . http://www.warmboard.com/media/141
It hasn't changed

Listen to what the others have said and don't do this in the wrong order , hell you don't even know what spacing you'll require yet or if radiant floor can heat the space . Sometimes it cannot , just a fact .
Many guys right here design systems given the proper information , one of them may be a good candidate for you to contact about your home .

PhotoGuy

Thanks all for the comments so far. I am enjoying learning the stuff I have so far. I am cognitive that a little knowledge on my end can scare you guys! I’m not in my responses trying to be “in your face.” I’m just trying to make some sense if you guys like the Heatply or the Climate Panels more (I’m guessing on my research I know the answer.)

IRONMAN: You say I’m diving into the middle by not having the load calc done. Suppose I came to a HVAC guy that specializes in radiant floors and said, “I am going to use “Climate Panels” and I need you to do the rest of the system.” Are you saying that this would be impossible? If so, why do they (Climate Panels) only come I believe in two sizes? Yea, I would agree that spacing would matter but they are a “fixed” product. Likewise, I’m asking about what I believe is replicating exactly one known product and replicating the other. On the second one, the aluminum wouldn’t be glued to the bottom of the panel. (I did research tonight and found that Climate Panels aluminum is .005 thick. I would actually be using flashing that, at the about the same price, is .018 thick. I could use the .005 thick aluminum to match and than for each panel (other than the glue) they would be apples to apples – I’m just building what they did! My “guy” could then use the same specific numbers that the manufacturers use. I could design the spacing based on what I’m told from there. I’m looking if this is a possibility at all and just looking for input at this point. No use getting all excited about doing radiant floors if I can’t reduce the cost to make it affordable (Yes, I want it also done right. At the same time, I believe that DIY can be done for this part to make it affordable.)

RICH: I have been reading for days about this stuff and I actually read in an old forum post (I believe from 2008) where some guy suggested graphite! Not much was said later in the lengthy thread but neat to see that he was on to something way back then. The “mechanical-hub” link I didn’t see anything about them but I did eventually find the “Flexplates” you might be referring too. Interesting product but it is designed for under floor applications. In my case, impossible at this point. I’ve seen all the Warmboard videos. Excellent product I can’t afford (both price and 1-1/8" thickness).

I can also tell you that the place I’m building is insulated well. R38 ceilings, R19 walls, all joists R19, new dbl-pane Andersen windows throughout, etc. I’m not worried at all that a radiant floor will work. (I did have a load calc done in the past and I have a layout of 8” throughout the cabin. What, at that time, it was as far as tubing size, etc. I have no idea. Obviously this will all be done again.

Snowmelt

As soon as a customer says that they can't believe the price of a product and I can or think they can make the same product cheaper is when I start walking away from the job.
Hey photo guy take a loan from the bank and get the job done correctly.

Or

Just go for it, it will work.

Gordy

Jumping in the middle. First you would go to the specialist, and say i want radiant floor heat. He in turn would do the load calc. Determine what method of radiant floor installation will off set the load on a room by room basis if possible, or if needed how much supplementation radiation would be needed to compliment the RFH. From there budget would dictate product chosen that would fall into the means to give the required out put needed.


If over the top is your only means then you have narrowed it down to the sandwich, or panel method. This is by far the most responsive, and provides the lowest supply temps which reduces energy consumption.

So now it boils down to how much build up you can do to make the sandwich, or panel thickness plus finished floor coverings.

Tube spacing is crucial in reference to further lowering AWT, prevent stripping, and or boosting btu output.

Aluminum heat transfer plates can't say enough about them extruded is superior, to anything less. so gauge of plate is very important. .0625/ .050, anything less you'll make more Btus drinking a 30 pack then taking the empties, and trying to make plates out of them, look at radiant engineerings web site that's what you want. They also show sandwich methods. The tube groove detail also important omega style is superior. Tube Contact, and conduction!

Warmboard does make a warmboard R r standing for remodel I believe it's 13/16 thick with all the bennies of warmboard structural panels.

So warmboard, raupanel, roth panel. All have high outputs do to the aluminum transfer plates

So how you gonna fire your floor, and dont say tankless, or tank water heater.

Harvey Ramer

I would like to interject something here. In the first post I read, "above slab install" . Question becomes, is the slab insulated, and if so how well? If it is uninsulated, you will definitely need a thermal break between your radiant and the concrete. Otherwise the downward heat loss will make your system very sluggish and inefficient. How much space do you have for a radiant buildup?

Gordy

He says his floors are insulated to r19. Conflict with what "above slab" means here. I was assuming sandwich method.

Harvey Ramer

Gotcha.

Rich_49

I was not referring to Flexplates which go under the sub floor . The mechanical Hub link shows one of our projects that used the Sunboard graphite panel . Much more cost effective than many of the other products you mentioned prior .

icesailor

Sometimes, people with Champaign taste with But Light wallets, should settle for a good quality Craft Beer.

PhotoGuy

My mistake - not above slab, but above floor.

ICESAILOR: Great point! Most good quality Craft Beer is homemade or came from such recipes.

GORDY: Yep, panel method only. I gave myself a 1-1/2” leeway with doors so no problem there. Obviously I don’t want to go any higher than need be. Let me ask you this: You state that the gauge of heat transfer plates is so important (“… .0625, .050, anything less you’ll make …"). But, I’m reading that Warmboard ( which almost everyone uses as the standard by which others fail to measure up to) is only .025 thick. From the bit of reading I’ve been doing, I’m seeing that the idea with Warmboard is the transfer of heat across a longer area. More contact with more floor equals efficiency and comfort! At what point does thickness matter? I’m thinking that there has to be a cost trade-off at some point. Is it thermal mass we want from the plates or thermal transfer? I'm guessing, based on my reading, that the mass thing is not what most people are looking for. Appears that nowadays it's all about response.

RICH: Got it. You had me going so I looked into it more and was reading how great graphite is. I thought why hasn’t someone made a panel yet with a graphite sheet coating??? I then saw your last post and there it is! Went over to Sunboard web site and was surprised that they have the cost on their graph as “$$$” and not the “best” when it comes to comfort, output, etc. I thought graphite was going to be the “cat’s meow” when it came to cost/benefit ratio (cheaper than aluminum with faster response times). I might be wrong but the cost on their chart is listing it as highest cost (of their products). What does a 4x8 panel go for approximately? You (and the idea of graphite) still have me intrigued! Based on what I asked Gordy above ... I'm guessing that graphite is all about transfer of heat across an area and the thickness is not as important???

Again, THANKS everyone for chiming in. I’m learning much here as along with the other reading I’m doing.

icesailor

There's a rumor around that the real reason that the Pilgrims first landed at Provincetown and then Plymouth, MA was because they ran out of beer on the voyage. That beer was a safer liquid to drink that some old months old barrel of water.

Another not often mentioned cause of the 1930's depression was Prohibition when outlawing the making and sale of beer and booze. It dried up the market for American grain for beer, and the farmers were going broke. Then, the loss of tax revenue from the sale of beer and booze pushed the country over the financial edge.

Craft Brewers and distilleries are a significant source of tax revenue. Same as wine.

With the loss of tobacco revenue, they need to find something else to tax. Colorado might be on to something.

Gordy

Warmboard is giving a continuous conductive surface to transfer heat so they can drop the gauge of the aluminum layer a bit. An extruded plate is a more quality manufactured process, and grips/ holds the tubing far better than light gauge stamped plates. And yes mass helps.

Remember conduction is king in radiant transfer. From the water through the tube wall through the plate to the surface. The more continuous, and conductive the path the more efficient the heat transfer. Is there decreasing returns on cost sure, but quality plate manufacturers have already done the math for you thus the size of their plates. Giving the balance between good heat transfer, and cost. They want to sell you plates, but good ones won't bow to the cheap stamped knock offs.

You asked for our input. It's up to you to make the choices. I do realize budget has its effects on choices. Just don't let the cheap gene take over. You get what you pay for.

Rich_49

Gordy is dead on . The reason the below floor plates have to be thicker and have more mass is that they must transfer energy through the sub floor also . Warmboard and Sunboard are right below the finished floor and have contact with the entire surface . this is why the coverings can be so much thinner on these products . Mass means much less when your right into the heated surface and not needing to get through additional resistance . Keep in mind also that they start heaating the room much faster having an average of 2/3 less material to (Rvalue) to deal with .
Sunboard is not out of this world expensive as many think Warmboard is . You should call or e mail Jim Skeldon for a quote . Tell him where you heard about it . Also much easier to work with as it comes in 2 x 4 sheets , less waste also . I have used both products and unless specified would prefer Sunboard . Houses are similar in comfort and it is more economical in many ways .