Radiant floor 140x50 shop
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Mr onetwo
Well-known member
On a slab that big you are crazy if you don't hire professional design and installation help.Should use 3/4" PEX ...not much fun to deal with.
gnpenning
Well-known member
This might belong in the heating and ac section?
I put radiant heat in a 40 x 70 slab last summer and got all my supplies from Menards. I used 1/2" PEX and broke it up into multiple circuits to keep the runs the proper length and to separate some rooms so they could be kept at different temperatures. Two inch rigid foam was used under and around the slab. An excellent source of information is Radiantec.
Tom
Tom
I get a lot of stuff from supply house ... use any quality PEX.
With a shop that size you should give some thought to how you will use the space -- zone for comfort and savings. 3/4 pex does allow for longer runs .. but you really must do the math.
Often industrial spaces use larger Pex with hotter water when there are lots of open doors and other large air movements.
With a closed space you want lower water and closer spaced 1/2 for efficiencies. More PEX closer together get faster response and lower temp water = savings in energy
With a shop that size you should give some thought to how you will use the space -- zone for comfort and savings. 3/4 pex does allow for longer runs .. but you really must do the math.
Often industrial spaces use larger Pex with hotter water when there are lots of open doors and other large air movements.
With a closed space you want lower water and closer spaced 1/2 for efficiencies. More PEX closer together get faster response and lower temp water = savings in energy
BD1
Well-known member
Have a real HVAC enginneer for the calculations. Spacing, length of runs, temperatures, all affect the performance. Sure anyone can roll it out and it will work. For optimum results for it right. You're only doing it once.
I did radiant floors 50 years ago. Back then it was all 3/8" copper. We even did it with plastered ceilings.
Sent from my iPhone using Tapatalk
I did radiant floors 50 years ago. Back then it was all 3/8" copper. We even did it with plastered ceilings.
Sent from my iPhone using Tapatalk
JeremiahTRD
Well-known member
https://www.radiantcompany.com/
I used them for my 5000 sq. shop.
They can help with design layout equipment sizing etc..
They use an on demand Takagi Hot Water Heater for there systems. So it's not a true boiler. but it works great and has a warranty. Also costs way less too.
They also prebuild your system and ship it to you in a box so it takes all the hard stuff out of the equation.
My shop all in was around $8k for everything.
For your insulation I would highly recommend finding a reputable spray foam insulation company. Have them spray 2 Inches of closed cell foam on the ground instead of the foam board. The foam is monolithic so there are no seams etc.. its a much better system cost is probably on par with labor and materials for foam board products.... No vapor Barrier is needed with closed cell foam.
I used them for my 5000 sq. shop.
They can help with design layout equipment sizing etc..
They use an on demand Takagi Hot Water Heater for there systems. So it's not a true boiler. but it works great and has a warranty. Also costs way less too.
They also prebuild your system and ship it to you in a box so it takes all the hard stuff out of the equation.
My shop all in was around $8k for everything.
For your insulation I would highly recommend finding a reputable spray foam insulation company. Have them spray 2 Inches of closed cell foam on the ground instead of the foam board. The foam is monolithic so there are no seams etc.. its a much better system cost is probably on par with labor and materials for foam board products.... No vapor Barrier is needed with closed cell foam.
Firebrick43
Well-known member
2 or 3” Dow board can be bought for less than half cost from places that reroof large commercial/industrial buildings. I don’t know whom you have local as I am in Indiana but I know there are some in the northeast. The foam I bought was 3” and was nearly flawless/new looking. They had some that was more beat up but would do quite nice under a slab still.
You can use 1/2” pex for the floor still. Length limit is 250’ on 1/2 so one loop should be to the end of the building and back. Spacing for 1/2” should be 8-12” depend on insulation levels of the walls/ceiling. If you layout you tubing carefully and keep each loop exactly the same length you can save significant money as you won’t need manifold with balancing valves on each loop. A building that size I would place 2 or 3 separate manifold spaced out for the loops to come back to.
Use the expanding propex system with pex A oxygen barrier tubing. It doesn’t restrict flow like crimp fittings, is more leak proof and if linked a heat gun can work it out unlike pex b or c which has to be spliced.
I highly recommend this text book for designing systems. It’s a college text book and can be dry but has all the math. “Modern hydronic heating” isbn 0-8273-6595-0. This is an older edition which is fine. I think I paid 75$ for one but even at 100$ it’s cheap and excellent education. Cover manual j calculations, flow calculations, spacing, layout, and all the different control methods and equipment. Even has a disk with software to do many of these calculations but the older version is 3.5” floppy. I am going to assume the new one is cd rom.
As far as radiantcompany, imho they are hacks. If that offends some I am sorry but their preassemble set ups are over price for the quality they are, and any company that pimps open systems should be though of as hacks. I was going to go with them at first as their marketing/information the have looks good but as I was educated by the above book I realized the many faults with their setups.
Spray Closed cell foam absolutely will absorb water in contact with the ground or other wet locations. I have witnessed it absorb water (although much less than open cell)even in roofs/walls and in boats where it’s used for flotation. On the other hand I have seen Dow xps used in a floating dock for years and not absorb any appreciable amount.
As with yeltdog I have found supplyhouse the best cost and service. They also sell different grades/brands allowing you to choose the level you want. Ie no one sells American made ward fitting locally any more and the Chinese ones the local stores(big box/contractor supply house/ and mom/pop) pimp are guaranteed to leak
You can use 1/2” pex for the floor still. Length limit is 250’ on 1/2 so one loop should be to the end of the building and back. Spacing for 1/2” should be 8-12” depend on insulation levels of the walls/ceiling. If you layout you tubing carefully and keep each loop exactly the same length you can save significant money as you won’t need manifold with balancing valves on each loop. A building that size I would place 2 or 3 separate manifold spaced out for the loops to come back to.
Use the expanding propex system with pex A oxygen barrier tubing. It doesn’t restrict flow like crimp fittings, is more leak proof and if linked a heat gun can work it out unlike pex b or c which has to be spliced.
I highly recommend this text book for designing systems. It’s a college text book and can be dry but has all the math. “Modern hydronic heating” isbn 0-8273-6595-0. This is an older edition which is fine. I think I paid 75$ for one but even at 100$ it’s cheap and excellent education. Cover manual j calculations, flow calculations, spacing, layout, and all the different control methods and equipment. Even has a disk with software to do many of these calculations but the older version is 3.5” floppy. I am going to assume the new one is cd rom.
As far as radiantcompany, imho they are hacks. If that offends some I am sorry but their preassemble set ups are over price for the quality they are, and any company that pimps open systems should be though of as hacks. I was going to go with them at first as their marketing/information the have looks good but as I was educated by the above book I realized the many faults with their setups.
Spray Closed cell foam absolutely will absorb water in contact with the ground or other wet locations. I have witnessed it absorb water (although much less than open cell)even in roofs/walls and in boats where it’s used for flotation. On the other hand I have seen Dow xps used in a floating dock for years and not absorb any appreciable amount.
As with yeltdog I have found supplyhouse the best cost and service. They also sell different grades/brands allowing you to choose the level you want. Ie no one sells American made ward fitting locally any more and the Chinese ones the local stores(big box/contractor supply house/ and mom/pop) pimp are guaranteed to leak
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I did my own garage and I have to echo a lot of firebrick’s feelings. First this is a big building and little mistakes in Your heating system could cost you a lot over the life of the building very seriously consider getting a professional for this even if you just do the installation yourself.
If you are going at it yourself definitely get the book modern hydronic heating it is pretty much the Bible of heating systems. An additional resource is idronics on Caleffie’s webseite they also have several good YouTube videos many feature the writer of modern hydronic heating. I doubt you will be able to beat supply house on price for quality components. I would personally recommend pex-al-pex it lays nice the oxygen barrier is sandwiched in 2 layers of pex to keep it protected and the compression fittings on manifolds are easy. When you have your building finalized look up loop cad you can use it for a month for free it does an excellent job laying out your pipe and will help keep everything balanced just print off and save the files unless you want to pay a lot of money for it. Start searching now for a used stapler it will make life easier and after you are done you can sell it for what paid pretty easy.
If you are going at it yourself definitely get the book modern hydronic heating it is pretty much the Bible of heating systems. An additional resource is idronics on Caleffie’s webseite they also have several good YouTube videos many feature the writer of modern hydronic heating. I doubt you will be able to beat supply house on price for quality components. I would personally recommend pex-al-pex it lays nice the oxygen barrier is sandwiched in 2 layers of pex to keep it protected and the compression fittings on manifolds are easy. When you have your building finalized look up loop cad you can use it for a month for free it does an excellent job laying out your pipe and will help keep everything balanced just print off and save the files unless you want to pay a lot of money for it. Start searching now for a used stapler it will make life easier and after you are done you can sell it for what paid pretty easy.
Flail
Well-known member
Pexuniverse.com was easy to work with and fast delivery.
The OP has not been back ...... but, be careful of the "open" systems ... and the use of non PEX products.
I use the Viega Pex for slab and in plates as it is 4 ply and the 02 barrier is not the outside coating ...
I have used Warmboard in the last few projects .. my first with that product was back in 04 when it was quite new. You use PexAlpex for that and I must say I was impressed with the Bluefin Pex product they resell .... same with the one Bluefin manifold I needed. Good value.
I have used PexAlPex in a slab as well .... when I needed the memory -- it was an insulated over-pour. Pex Al is easy to work with in many situations
I use the Viega Pex for slab and in plates as it is 4 ply and the 02 barrier is not the outside coating ...
I have used Warmboard in the last few projects .. my first with that product was back in 04 when it was quite new. You use PexAlpex for that and I must say I was impressed with the Bluefin Pex product they resell .... same with the one Bluefin manifold I needed. Good value.
I have used PexAlPex in a slab as well .... when I needed the memory -- it was an insulated over-pour. Pex Al is easy to work with in many situations
How did working with warm board go for you? I’m looking at putting that in a few rooms of my house we are still in the planning stages though. Did you use their layout services?
I agree with the quality of blue fin pex-al-pex seemed to lay out nice and hold its shape hardly had to use any staples. My only concern with the bluefin manifold was parts availability if I need something but for the price I will just have to deal with that in the future.
karoc
Well-known member
Tom's Tech- I have watch I think all of your Youtubes,they are fantastic.
Warmboard a nice product ... have only used the full subfloor version. Being 1 1/8 thick the floors end up being solid. Not cheap .. on the other hand it's foolproof.
The Bluefin manifolds share parts with others. think Warmboard's branded are Bluefin. ... They use Blufein and at least one other supplier for the PEX. I have always used the AL Pex with the Warmboard.
I used 3 Cross manifolds on this project as well. I did a large living room that needed 11 loops of 3/8 regular Pex. Decided the best way to add some control was a zone valve for the whole manifold ... figured I would try the Bluefin. I was impressed with the quality .. my installers as well.
The Cross are really slick .... while expensive when you add up all the parts if you need to control the zones .. they look better. They come with a control all set up --- all you need to do is connect a thermostat.