The Wall
Forum / Radiant Heating / Ideal pex routing for underfloor install?
  • Post a Reply to this Thread

    Ideal pex routing for underfloor install? (28 Posts)

  • Mustangous Mustangous @ 2:09 AM
    Contact this user

    Ideal pex routing for underfloor install?

    Hey All, Great Forum with a wealth of knowledge!

    Hope someone can help me out about routing the pex for underfloor/joist bay installation.

    I am getting ready to run 1/2 pex on 8" centers with thermofin plates. Before I do so I am trying to layout and calculate all loop lengths on paper first. So when i start, I know exactly how and where everything will be.

    My main question is how to run the loops. All the examples i have been seeing online look like the first image i posted. But I would thing that I would get more even heat if I ran the tubing like the second photo (sorry for the poor drawing). Im shooting for a 10 degree drop between the supply and return so not sure if it would even matter and im just being to picky here.

    Thanks!
  • This post has been deleted!

  • Mark Eatherton Mark Eatherton @ 9:04 PM
    Contact this user

    None of your pictures came through...

    Regardless, in an ideal setting, the manifold would be located near the center of the area being heated so that you don't chew up a lot of tubing getting from the manifolds to where the heat needs to be. If that is impossible to achieve, you may have to consider insulating the home runs, otherwise you will be putting heat where you don't need it, and not putting it where you want it...

    Keep your tube circuit lengths under the recommended lengths and keep the length differentials between the longest and shortest lengths +/- 10%. Otherwise, make certain you have balancing provisions at the manifolds.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mustangous Mustangous @ 10:51 PM
    Contact this user

    Pex Routing

    opps, I double posted and the one with the images might of got deleted.
    This post was edited by an admin on November 27, 2013 11:01 PM.
  • Mustangous Mustangous @ 11:21 PM
    Contact this user

    tough to put into words

    For some reason I'm having a hard time explaining this in words.

    I am going to have 1 zone, 6 loops on my first floor working its way across from one end of the house to the other. There will be roughly 4~5 bay joists per loop. 1 loop will only cover 4 bays out at the furthest ends the house because Im also counting the distance it has to run from the zone manifold that is located pretty much center of the house. My thinking was that if i ran the pex as in the first image, there would more of a temperature difference on the floor between one loop to the next. Since I should be only about 13* delta between supply and return, it wouldnt be a substantial difference, but there should be some, right?

    I was just thinking if I ran the pex tubing like the second picture, the temperature on the floor would be a little more even. For example, the midway point of the loop would span the area of the floor that its covering and start heading back to where the loop started.

    Hard to explain...

    Anythought?
  • Mustangous Mustangous @ 11:46 PM
    Contact this user

    example

    Here is a quick illustration to help understand what im trying to explain with the temperatures across the floor if I routed the pex like the first pic. I would start the begining of the loops closer to the outside walls ( left and right).

    am i putting too much thought in this?
  • Weezbo Weezbo @ 12:58 AM
    Contact this user

    Mustangous ,

    here is some couple few things to consider .
    1. every time you go from bay to bay ,
    you lose some heat transfer through conduction thru a plate attached to the floor .
    ( because the hole from bay to bay is not at floor level for one , and there is loop bending radius to consider .)

    2. If you bring your loops to a central location , you can run out 3/4" to the boiler /heat source which tends to keep all of the lengths identical . "Rim joist are little trickier ".
    any where plumbing or wiring comes thru the floor , well it takes some navigational abilities to circumnavigate it before going back to straight line theory again.

    3. nothing says that you cannot add a rad panel or even baseboard to bump up the temps . while they run on convection as part of their agenda, the floor near the perimeter may be a bit cooler than you might have thought. steer clear of the tubing is the precaution i leave with you .

    there are the first few of the couple few ... would you like to hear any more ?

    Weezbo.
    This post was edited by an admin on November 28, 2013 1:05 AM.
  • Mustangous Mustangous @ 3:49 PM
    Contact this user

    more detail

    1. Not sure I understand, Isn't heat transferred through conduction with the transfer plates?
    I have to loop anyway and was thinking the larger radius loop would be better (jumping to next joist instead of tight bend staying in same joist). Are you saying that I am loosing conduction on the loop area, wouldnt I loose heat transfer anyway if I looped withing the bay or went to the next joist?

    2. Each zone will have a 3/4" line from heat source to the distribution manifold that is almost central located.

    3. I hope i will not have to supplement this with any other heating.

    attached is how im thinking to layout the pex and my joist layout, hopefully start asap. The far right joist bay is tight, 9.5 wide at top and 11 at the bottom (because of the staggered joists) so i put the bend at the bottom section. Im trying to keep the bend radius as large as i can, thus laying the loops out this way.

    More info:
    The manifold will be located on the first floor in a small closted (closet is only for the distribution manifolds for the 1st and 2nd floor and data stuff (router/networking)) under a landing for the stairs.
    As in the drawing I am planning on running the loop along the main center beam/header in the basement to avoid a lot of holes drilled through the joists. Only holes in floor joists will be at the ends by the rim joist.

    Does this layout look good? any Suggestions?

    Thanks for the reply!

    Image isnt poping up correctly.. heres a LINK
    This post was edited by an admin on November 29, 2013 4:10 PM.
  • Weezbo Weezbo @ 7:31 AM
    Contact this user

    yesterday i transported you pic to paint ,

    and just for the heck of it , on the one pic on the left vs the one pic on the right i made a rough approximation of how many feet of lost radiation by plates did each represent .
    then i over estimated the plain jane normal way against your idea , well , you are probable well over 40 ' of wasted radiation on just those two pics alone were the pics showing equal lengths of pipe.
    that is to me , backwards to the way to roll. not to mention the added work .
    if there is a difficult way to accomplish the same thing i have probably seen it and some of its close cousins .
    one of the neglected aspects is economy of pipe .
    looking forward , the pipe to open air loses some btu's per hr also .every time you change planes and every time you ad curves uies swoopy 90's or go three dimensional :) 3D well, the plates sorta dont work .
    so you also must consider the bending ratios of that dimension , therin is the crux of the matter .
    running things returns lets say , along a beam well thats not a bad idea , you have a surface of a piece of thermal mass unhindered by more variables for a path ... just going with the left side pic you lose say close to 18 " per bay on the outer loops in each bay and 2 '-8" ish on the two that change dimension and cross over thats like 4 ' or so call it 5 even per bay.
    the other way you lose closer to 4 ' per bay on the loops that go bay to bay and about 6 feet on the ones that change dimension .. so thats like 10 ' per bay your tails or journey there to the end of the return i called a wash .. i do not see that as economical comfortable in any way . by the way it makes for more targets ...
    ....
    insulation detail , lack of two holed squeakers for two pipes thru one hole , means there would be still more snafus along the way squeakers are good to keep the pipes from continual stress Kinking , scraping , while allowing temp differences for expansion all come into play in your over all comfort.

    i think that pretty much covers your first question
    .although when you want to purge air via a pump thru each individual loop of half inch it will be seeing you again , and when you go back to insulate it and vapor barrier it ..
    and find out that all these ups and downs isn't making that any easier .. threading it thru all the outside holes you may find to be more of a challenge than you needed to be doing as well.
    i need to get some rest . it is 3 30 in the a.m. here...
    my day went long :)

    see you tomorrow and i will add some more ideas on things that might be more in line with reducing wasted effort and pipe and fittings and time ...
    Weezbo.
  • Mustangous Mustangous @ 8:22 PM
    Contact this user

    thank you

    Weezbo,
    Thank you for your time to help and give some insight! I didnt think these things would play a part. I was under the impression that mainly only the heat transfer (heat loss) was from where the plates were and minimal, if any was lost elsewhere since pex wasnt a great conductor like copper or alumumin.

    I will draw up another layout with the typical pex layout and post it up, but a couple questions:
    Would this be the way to lay the pex out ---> Pex Layout ?
    Also if I come across, say the front of the house, then run up and down the bays, how far do i drill the holes from the rim joist? I suppose from your last post I should drill 2 holes, one for the run, than another for the loops for each bay.
    1-1/2" holes?

    Thanks again for your help.
    This post was edited by an admin on November 30, 2013 8:22 PM.
  • Weezbo Weezbo @ 12:18 AM
    Contact this user

    yes ,

    that would work , however ,
    roll with me on this ,
    1. if you drill a whole 1- 3/8ths one squeaker can fit in the hole with one piece of 1/2" or you can use 3/4" squeakers and one piece of 3/4" can fit the pipe being ok with that .

    2, because it is a dimension change perpendicular to the surface that you intend to attach the plates , you are money in the bank to drill a 1 and 3/8Ths hole such that it is 3/8ths from the bottom of the top cord . that is quite often permissible by many manufacturers and most build inspection departments .

    3. there are also larger plastic squeakers for larger tubing , and while 1- 3/8ths can be placed just about anywhere , 2 inch may require dimension from the end of joists.

    like if you wanted to drill 2 and 5 or 2 and 9/16ths you may have to be 8 inches from the end of the bearing closest to you on outside walls ,inside beams or some load bearing shear walls .. each manufacturer has some set of rules they are certain the structural engineers that they hired wont bash them all day long over ...lol..

    they may say well you can drill 3 " holes , 2 feet away from an outside load bearing wall , if they are no more than 1 " to the nearest chord ,
    for ease of operation go with find out what type of floor joists that you have and get the straight scoop..,
    some may allow closer spacing if you add 1/2" plywood to the surfaces of the web that you drill thru .. if it is not a big issue one 2 and 5/8ths or 2 and 9 1/16ths allows you to simply fasten one end after threading it thru the holes then with an uncoiler and or a friend you can slowly and carefully pull the pipe thru and once you are out at the perimeter add a little more, then go back and pound it into the plates with a rubber mallet . when you get to the end of the plate go about 6 7 inches out and tack it with a talon clamp .
    use both hands to bend it slowly without kinking it so it is now in alingment with the other plate in that bay boink it with a mallet about a foot add another talon clamp and continue boinking the pipe in with the rubber mallet till you are at the end of the plate .
    go to the next bay same deal again when you and your friend get to the last bay you will have some pipe left over you could if you drilled larger holes run both tubes thru the same hole and larger plastic squeakers or whatever when you have threaded that end thru the holes go back pound the slack into the rest of the last plate .
    maybe tack a talon clamp 6 inches or so away from the plate and go back to each bay and bang in a talon clip rigthy tighty to where the tube leaves the plate that looks decent and keeps it in better alingement where it leaves the plate .
    you may even find htat the one hole is not binding any of the pipe and it can be zip tied together to keep it looking nice thru the larger hole 8" away 3/8ths of an inch down from the top cord.

    the 8 " is just a number remember , it will allow you some elbow room to work so that is not altogether undesirable ...

    small zones of 600 feet help where you may not particulairily need heat 24/ 7 . so , consider zoning before taking off on your adventure.

    may be you can run the other zone "Hotter " or have more BTU's available for the livingroom in the evenings or whatever. one more thing in this

    keep your mind open to obstacles when laying out the plates and also consider laying a piece thru the hole plate to plate end with some tube boinked into it that way you can with 5 feet of tubing maybe six determine a specific starting point for laying out the plates and checking if you can get a straight line thing going on, earlier on..

    i hope this stick s with you .

    because when you cut the plates to fit making one cut on a plate and cleaning the burrs off with like a pipe reamer on both sides of the cut makes for a more reliable system overall.
    if you take that same piece of pipe you were using to start the lay out you can "Practise hammering Down 1 foot into the cut end that you de burred and then pulling it back out of the plate.
    check the pipe for any signs of like o barrier cuts the stuff is tough buh just having done that much will make it a whole lot easier to hammer UP into place and less likely that you will be cutting lines into the pex.
    this is probably over loading the brain cells...
    however read it twice and you will see that there may be some things that will help you in your contemplation of your project....
    *~//: )
  • Mustangous Mustangous @ 12:14 PM
    Contact this user

    Thank You Weezbo

    1. Is this what you mean by squeakers?
    Suspension Clamp

    2. My floor joist are 2x10's so dont think I have top and bottom cords as you refer. Having said that, I have been going by This Guide for drilling holes and holes should be 2' from top or bottom of joists. But I think that is basically the same as 1/2" from the bottom of the top chord if I had that design. I think that is for clearance for nails. Also according to this guide, there doesn't seem to be a minimum distance to stay away from the rim joist, so should I assume as close as I can that is comfortable to get a nice straight hole drilled into?

    Just another thought, I already made the 6 loop manifold, but would it be better to run a 3/4" supply and return header (instead of manifold on first floor)? Run the header along the the front of the house by the rim joist and just tap off it with 1/2" loops at the joist bays they would be heating?

    Thanks again for all your help! Very much appreciated!
    This post was edited by an admin on December 1, 2013 12:15 PM.
  • Weezbo Weezbo @ 1:11 PM
    Contact this user

    nope ,

    http://www.siouxchief.com/products/support/supply-hangers/plastic-cts/cts-isolators/pipeeye
    these are something that is similar in application and use however at or near the same price point.
    ....
    the clamp you show we call "Micky Mouse ears"
    The wholesale companies usually have them in pretty much the same area as all these plastic clamps and squeakers they basically are all protecting the pipe from abrasion and expansion . and all are helping with the alignment as it were .

    pex tubing insulators , we call Squeakers because they not only protect from abrasion the add support and keep the expansion noises down so that the home owner is not wondering where all thee squeaking keeps coming from every time there is a call for heat ..
    we use these on copper tubing as well. save yourself time by not using screws to hold them in place and buy them in like 100 count or 50 count bags .
    the drills we commonly use are what are refered to as right angle drills .. my old wolverine was replaced by a black and decker same design now Dewalt makes them ,
    there head spaces the pipe away when held square to drill 1/-3/8 right where you want them or youcan turn th handle 90 degrees to get closer and drill at a slight angle ..
    Milwalkee also makes a Heavy right angle same sorta deal faster revs is what i do not like andthe extra weight , many plumbers use the lighter version they make and they are ok for the most part with a smaller body a different handle (More like a 3/8ths drill the fact they are right angle drills allows you to get two hands on them to keep the cord from twisting the living crappola out of your wrist.. then there are some beefy Hole hoggs .. i would not advise you to buy one , they are stronger than one might imagine lol..
    i owned one of them many decades back .... they have a slow roll buh even at that can wrap you around their little finger sort to speak.. start a thread Best drill for plumbing and bingo the horror stories will begin to arise over going air born and what not lol... source ? being on a ladder leaning out to drill a hole and the hole hog or right angle spun the guy off the ladder and wrapped him around a steel post...: ))
    do not ask me how i might know this..
    *~//:)

    the header well couple few years back 2 X 3 or so maybe 7 or eight even , i burned some daylight with a designer at Wirsbo and showed him a configuration similar to his two three and 4 port PLS fittings that i thought would help radiant installers . basically they allow you to run 1/2" into them a piece with a 3/4" boier purge a place to put an air bleeder and a place to connect the supply .. all in one pls fitting sort to speak .
    well i have some and they are the definitive headder in my opinion .
    Upunor makes them ,

    here is one he made i like it too because it is tight and still has enough half inch ports for a purge and could be laid flat under a floor.

    http://www.uponorpro.com/Extranet/Layouts/ProductAndToolModal.aspx?id={53A4FEC8-22FE-4490-BBA6-0B4B2835EB9E}

    the guy is always thinking and really there is so many things he would probably like to build because the industry is one that like trucking "Rolls" in America .

    if you get one of their catalogues for this year and look at the multi port PLS you will find a variety of configurations ..i use these fittings for radiant heating as well as plumbing potable water.
    the picture of his six port i could even see in ground warming and green house , applications ,land scaping irrigation apps , maybe even some snow mely could be made less of an ordeal with fittings as tight at this .

    ...hope the ideas help too maybe when you see these fittings you will wonder why you burned so much time making a header .
    i can see , a six port Thru fitting in my minds eye , Now That , might not even be that bad a deal ...lol.. there are so many good human beings working in our industry
    .. some we never meet or even know they exist , each doing their part and mostly no one would ever even know all the good they do over their lifetime of work..
    This place i Love this place : )) heatinghelp .com really has the human being side of things together ... *~//: )
    look up watering hole ... he he he in the search column ... maybe it will bring up and old post it is sorta interesting ....
    This post was edited by an admin on December 1, 2013 2:58 PM.
  • Steamfitter66 Steamfitter66 @ 10:55 PM
    Contact this user

    I'm pretty sure

    irc ibc code is the middle 1/3 and it can be anywhere in that middle 1/3. I prefer 1 3/4 holes n
  • Weezbo Weezbo @ 12:48 AM
    Contact this user

    somethings asking me to open a file,

    "Not sure I understand, Isn't heat transferred through conduction with the transfer plates?"
    yuppers .
    if you have 40 less feet per loop or more thats 40 less feet of transfer plates ....

    i say things differently however for what ever reason i seem to think it means exactly what i said .
    ....
    *~//: )
    you lose some heat transfer through conduction thru a plate attached to the floor ."

    the left side of example 1 shows approximately 24 '-0" of pipe loss to loops ,
    the second drawing shows approximately 64 '-0" loss for loops ,
    24 from 64 = 40 ,

    so i am saying that you are losing potentially 40 more feet of plates in the area described.

    ok , let's see, ... if you take and aim your middle fingers at each other , and your thumbs straight up , and then you point away from your body and look at the base of your index fingers of both hands and imagine your thumb was right there ...
    you would have just described what i call simply , the left and right hand rules of physics.
    right had rule being motion flux current , left hand rule being or field velocity and force.
    what these things are i am not into at the moment buh they indicate Vectors ...
    they are mutually perpendicular.
    their origin, lets call it for now, would be described as the base of the forefinger basically for want of the easiest description .
    these are what common shapes we see and agree look like in the physical world ,
    they are three D :)

    Ouspensky and the philosophers and meta-physicists i leave to describe the parts of object we are looking at and do not actually s
    ee, buh for now, roll with me on this , it has Dimension .
    that means in this case, that, the plane we are heating will not be able to "See" the pipe in a transfer plate, because like a snail ,(it, the transfer plate) , is traveling on a line on a plane . that is what i am referring to when i said "you lose some heat transfer through conduction thru a plate attached to the floor ."
    .....
    i suppose that is clear as mud lol....
    trust me it is poor economy .
    *~//:)
    This post was edited by an admin on December 2, 2013 2:06 AM.
  • Mark Eatherton Mark Eatherton @ 5:25 PM
    Contact this user

    I think you are putting way too much thought into it...

    I've had an errant employee pipe a room with the hottest fluid going into the center of the room and cooler fluid working its way to the outside of the room, and the consumer never noticed it. I discovered it during the anniversary check (1 year) because we had a non electric TRV piped backwards that was thumping, hence the discovery,

    Unless you have micro sensors built into the soles of your feet, you will not notice the difference. Remember, the fluid should realize a 10 to 20 degree drop through the WHOLE circuit. Negligible at best.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    This post was edited by an admin on December 1, 2013 11:23 PM.
  • Zman Zman @ 11:18 PM
    Contact this user

    Pex

    As for drilling the holes, your chart is correct. The reason for the 2" from the edge has to do with tension and compression within a structural members. That is a longer story.
    1 3/8" holes work well because the "buttholes" or "squeakers" as weezbo calls them are made for 1 3/8" holes.

    The first picture you posted is the best and easiest way to do this. Not only will your second idea not make any noticeable difference, it would be an absolute pain to do it that way.

    If I was looking to over think this, I would do a heat loss calc and then increase the concentration of plates in strategic areas. If you have a noticeable difference in temperature, it will be related to variations in heat loss from one are to another, not unevenness do to tubing layout. With the options you are looking at, the center of the house will feel warmer than the perimeter. To your feet it will all feel the same.

    Carl
  • Mustangous Mustangous @ 11:42 AM
    Contact this user

    few more questions

    Thank you all!
    Weezbo, makes sence about all the wasted pipe I would be using.

    Zman, your statement just made me re-think my plate spacing. Not sure what I was thinking but, yeah im over complicating this... lol

    I have the 8' thermofins waiting to be installed. My joist bays are 26'8" from rim joist to rim joist. Originally I was going to fit 3 8' plates in a row in a bay with it stopping 10" from the rim joist and with 6" spacing in between. (10" too close to the rim joist?)
    I bought enough and was planing on filling the entire floor like that, but just realizing what you said about the center of the house being the hottest, this would make that worst and not ideal.

    So now Im thinking just filling the joist bays like i said above, but only 3 bays around the perimeter/outside walls of house. Then either ill leave the center open or cut the 8' in half and put 4' in the centers as needed. We are in the process of adding a second floor on a ranch, so extras will be used up there. The first floor is my test area and will be much easier than the second floor due to all the obstacles in framing.

    So a few questions:
    How close or far should the plates be from the rim joist?

    SInce this first floor piping is in the basement, for this zone would it be better to run 3/4 supply and return line for a header across all the floor joists close to the rim joist and just tee off with ball valves for each 1/2" pex loop wherever needed? instead of a central manifold and running 12 (6 260' loops - 6 supply and 6 return) pex lines through the joists?
    This would also make the loops shorter and much easier install. Would there still be even distribution in each loop with running a header like this?

    Thanks for all the help, very much appreciated!
    This post was edited by an admin on December 3, 2013 11:45 AM.
  • Mustangous Mustangous @ 1:54 AM
    Contact this user

    Header instead of a manifold?

    Here is a header style layout apposed to a typical manifold setup. Would something like this be ok? This would make installation way easier and all loops exactly the same except for the first loop all the way to the left, it would be roughly 25' longer than the other 5 loops.

    Site not liking my files... Heres the Link to Pic
    This post was edited by an admin on December 4, 2013 2:27 AM.
  • Weezbo Weezbo @ 2:52 AM
    Contact this user

    i live in some different world ,

    it is very near the outskirts , ...of the , ... Twilight Zone.
    ...lol
    here heat that stays with us is a good thing ..lol so me going to get a 2 meg 121 % efficent and put it smack dab in the miiddle of the house ...who needs emitters ?

    this thing will heat way way up and theres enough iron in it to last for like days : )

    solly must be the CO getting to me ...


    Or it could be the turkey ... i have been freaking with a boiler for days ...
    first i over think things way too much .... and am always certain that if the manufacturer could get 87 % i could get 90 lol.. maybe even 91 ...
    of course deep am confident it is no way they are telling us the full story so there must be at least 5 more % there somewhere ...: ))) we just gotta brave it and think out of the box.
    "Huh?"
    this generally leads me into more and more work i ought not have had to do ....
    ok so enough of my Problem .

    it is getting colder again drat the cold Hurray for Global Warming !
    maybe in a few years our homes willself heat from radiation from the years of nuclear power plants production schedule of the land of China in conjunction with the one coal mine and new coal power generation plant they built at like one a week for a couple years now.
    the old saying of
    "I know you are trying to heat my house from your boiler ,...buh it is an exercise in futility "
    may have to give way to their steadfast determination ...lol...

    Sorry , i digress...
    i am a bit tired this evening although once i get some food in me i think i can help a bit more after i pass out and reawaken..
    i give you this as another thought , i have not abandoned you .. you seem to be picking up on all the ideas that are being offered from the vetranos of Hydronic floor heating ..

    like i said earlier it s not one of my more favorite ways to roll.
    and as you can see , there are "Hidden" reasons i might have for this opinion.
    my heat source and its location and the type etc and a host of other variables come into play when i let someone convince me that this is what they really really want to have me do..... Mag , here we have a few guys who think it is the best thing since toast and sliced bread , and like Mark will attest , there is more than one way to do things and the economy is there and so is the comfort .
    that , along with my trust that one of these guys will come along and have pictures of their work and fill you in on another set of How To from their repertoire , i have procrastinated a couple days ... hang with me a bit more ...
    that way , you may get even more out of the answers to your questions ...
    i am optimistic , for You .

    me go FOOD!
    *~//: )
  • Mustangous Mustangous @ 2:26 AM
    Contact this user

    thermofin transfer plate layout

    This is what I'm thinking on how im going to laying out the transfer plates and if I could get your opinions on it...

    Linky Here
    This post was edited by an admin on December 4, 2013 2:27 AM.
  • Mustangous Mustangous @ 1:39 PM
    Contact this user

    Can I use long headers?

    Hey all, would a layout with a header setup like this Link to Pic be just as good as a central manifold? The headers are red in the pic.

    This would be located in a full basement, thats not finished (maybe in the future)
    This post was edited by an admin on December 5, 2013 1:40 PM.
  • Weezbo Weezbo @ 4:36 PM
    Contact this user

    that looks like it would be some good coverage,

    then where ever the heat source was located , you would draw from one end of the long header and supply from another cross corner ,
    on the diagonal...
    and ,
    just for the sake of sameness ...
    make them identical lengths and put the new long headers in the building .
    don't whack one of them down because the heat source is closer.

    *~//: )

    look up reverse return and cascading supply temps .
    This post was edited by an admin on December 5, 2013 4:48 PM.
  • Gordy Gordy @ 9:17 PM
    Contact this user

    I'm looking at the design

    And thinking radiant floor joists as a novel idea. I joist design BCI, TJI, with a pronounced top flange width to spread the heat in an aluminum transfer capping material .
  • Mustangous Mustangous @ 9:54 PM
    Contact this user

    I like your thinking!

    Thanks Weezbo, thats a great idea, it would equal things out even more.

    Great, now i can get started on laying the plates underneath the subfloor since I got a plan of attack.

    Questions:
    1. The headers, would there be any reason to use 3/4" copper over 3/4" pex?

    In my thinking of trying to keep everything consealed, Im planning on drilling 2-9/16 holes 2" from the bottom of the floor joist so i can run the header through. Such a big hole because I have 2-1/2 od armaflex pipe insulation I plan on using for the supply header. It would also help finagle copper header through the floor joist if i use that instead of pex for the header.

    2.Any real benefit to insulate the return line too?

    3.Where i tee off the 3/4" header for the 1/2 pex loop, would there be any real benefit to have ball valves there? I cant see a reason to ever shut off a loop other than if one would spring a leak during heating season. There wouldnt be an area that would not be used, mostly all open floor plan on first floor.

    Gordy, that would be a great and inovative!
    This post was edited by an admin on December 5, 2013 9:58 PM.
  • Weezbo Weezbo @ 10:59 PM
    Contact this user

    well , purging fittings ...

    circuit by circuit is something that i do , even with a Spirovent or Caleffi micro air eliminators ... prior to anything to do with the heat source ..

    .... thats just me though some folks figure well who needs all that extra time and effort into it when i got a spirovent....

    and after many years of using some Ideal valves i read where they say they are not approved for heating by Wirsbo..:( i never had any of them leak ...and they are really tidy for each individual 1/2" loop come in straight and 90 degree 1/4 turn and well fit in line in pex.Souxi Chief may be making them these days and they have their act very together ...as they warranty their products . and are adamant on getting things that they do right.... i have no link at the moment for the fittings they have for the He pex pipe and aqua pex i use them on rehau tubing with the expansion collars as well.
    i also use the 3/4" 1/4 turn valves pex to pex my return i use He pex and supply Rehau . then when i am back out of the crawl space and or away from a job for a while it is no , '
    ' well maybe this is the supply,'
    thing going through my head ..
    i find these valves to be very reliable and leave access covers to them ....
    the panels are 14 " 1/8th square .
    fit perfectly in 1/2" sheetrock and have a nice day .
    i figured out comingiling before there was a printed code update ... would nt you Know it ! pex a pex a pex a pex a .. Hmm its all pex a ... Nice ...
    so that Turkey stew is still looky good brb..

    *~//: )
  • Weezbo Weezbo @ 11:08 PM
    Contact this user

    copper is made of metal so ,

    you have some more pre planning ahead of you.
    you will need a hole from out side so you can feed this through the holes that you drill ,
    remember, too ,

    not one kind of pex says ,
    fire up the mars station with oxy boost rocket propellant torch and target the tubing ....get what i am saying?
    therefore , not a real supporter of the idea mag.
    pex is easier to work with buh the hole from outside and some help of some sort inside will still win hands down over fighting things alone from within..
    This post was edited by an admin on December 5, 2013 11:11 PM.
  • Mustangous Mustangous @ 12:39 AM
    Contact this user

    Weezbo,

    THANK YOU FOR ALL YOUR HELP!

    With 2-9/16 holes up 2" from the bottom of the joist, I am pretty sure i can fead the copper pipe in the joists without a problem. Think its gonna be harder to slip the armaflex insulation over the pipe and through the joists at the same time.
  • Weezbo Weezbo @ 1:34 AM
    Contact this user

    Solly Mag ,

    i have been discussing Versa Hydro masonry wood heaters radiant contrlo strategies for a couple hours ...

    Winter is severe here so we do all we can to work out the best we can out of products and lower ownership costs of our homes ...
    Please look into heatinghelp.com from time to time . you can describe what you see on the new horizon ...
    *~//: )
  •  
Post a Reply to this Thread