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staple-up insulation

Bryan_16
Bryan_16 Member Posts: 262
in THE MAIN WALL
How much is enough? Am doing my first staple-up job and trying to insulate between joists and around plumbing pipes is a real pain. Can I install my insulation(reflective bubble) on the bottom of the 16" tall joists? Am heating with 115F water and heat transfer plates. Any draw backs to the 16" air space as opposed to th 4" that I am trying to maintain?

Comments

  • David_5
    David_5 Member Posts: 250
    If you used plates

    and they are fastened to the floor no air space is needed. Heat transfer is by conduction in your case.

    David
  • Mark Eatherton1
    Mark Eatherton1 Member Posts: 2,542
    I hope...

    your post had a mis-typed number in it. 115 degree F water is going to have trouble giving you much more than floor conditioning. You may have to up the temperature considerably depending upon the heat loss characteristics of the building. As for air gap, most manufacturers recommend 2" gap between the tube and the insulation. Don't waste your time with the reflective insulation. Once it gets dust on it, its spectral reflectivity is ZERO. Just use paper backed insulation.

    ME
  • Jamie_6
    Jamie_6 Member Posts: 710


    This is what I recommend!

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  • Mark Eatherton1
    Mark Eatherton1 Member Posts: 2,542
    Good Job Jamie

    I can use something like that if you don't mind.

    ME
  • hr
    hr Member Posts: 6,106
    With transfer plated

    I agree insulate against the plate and skip the reflective-ness. Better to invest in more R value.

    The KSU study used 5/8" air gap and a 2" air gap in their study. The 5/8 gap was a few BTU's better output. Although they used foam, thinking fiberglass would allow some convection loop inside the fibers.

    hot rod

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  • Floyd_5
    Floyd_5 Member Posts: 418
    Believe it or not....

    Mark, I have heated the large log house that I have post pics. of with 115* water all winter @ temps. to minus 10... it has held 67-68 with no insulation under it.... HO is to insulate and then I plan to cut temps. back more....right now without the insulation the basement is running a steady 70*....
    I would have never believed it if it wasn't my install and I was the one at the controls.

    My latest project, a fire house, 10,500 sq. ft. all slab.. is running fantastically @ between 85 and 120 water temps.
    Will give a full run down on that project when I am allowed to do so... it has a special feature and is working flawlessly so far.

    Floyd
  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    I'm about to

    do a job that is suspended tubing. The joists are TGI I beam type wood construction. The bottom of the top I beam is 1.5 inches. I talked with Wirsbo yesterday and they said that would be a good air space. I was thinking of cutting a thin foam board like R-max, perhaps, to fit in the joist space and stapling up against that beam to create the air space so insulators can just push their batts up against it. A little more labor and materials but peace of mind, priceless. WW

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  • Jamie_6
    Jamie_6 Member Posts: 710


    It's all you Mark!

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  • Bryan_16
    Bryan_16 Member Posts: 262
    Thank you

    all for the input. 115F is correct. I am just tempering the floor. Have an 8 ton GSHP supplying water for garage floor slab, basement floor slab, 4 ton AH, 3 Ton AH and staple up for masterbath floor. 115F is goingto be my max temp. The plates are installed directly to the bottom of the sub floor.
    I still think I need to insulate, but I dont understand why I wouldn't need an air gap. Don't the radiant waves need something to bounce off of?
  • hr
    hr Member Posts: 6,106
    With plates

    your heat transfer is largely conduction. It counts on good tight tube to plate fit, as well as good contact between the plate and the subfloor. Not a lot of need to bounce radiant waves when the conduction transfer is this powerful.

    hot rod

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  • hr
    hr Member Posts: 6,106
    Just make sure

    you have done your load calcs! There is a limit to output on suspended tube that can easily be passed if floor coverings are ever added or changed. Not a lot of room to move, output-wise with convection heat transfer. Wait till May's PM issue :)

    hot rod

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  • Bryan_16
    Bryan_16 Member Posts: 262
    thanks

    again. I have complicated this install more than necessary. Will not make the same mistake next time. Would fiberglass batts with the paper backing upagainst the tube be better than no paper backing?
  • Floyd_5
    Floyd_5 Member Posts: 418
    Why not use plates???

    Wayne, use the Wirsbo heavy plates.... then the insulation deal is not as critical....as HR has said, if you have a strong conduction going on then the dependency on the transfer through the air becomes a non factor.

    I just can't for the life of me figure out why anyone would try to make a "hot air" system out of a perfectly good chance to have a great "radiant by conduction" system....

    Gonna spend the dollars now or later... take your pick....

    Floyd
  • Floyd_5
    Floyd_5 Member Posts: 418
    Whoops....(nm)

  • Floyd_5
    Floyd_5 Member Posts: 418
    It makes no difference....

    the paper may make it easier to hold the fiberglass up there.
  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    I hear you Floyd

    It's a question of cost. The plates drive the price way up and out of some homeowners range. I do the heat loads so I know the suspended tube will work, and the boiler is cast iron so the lower temps are not as critical as would be with a condensing boiler. It will work and they will love it. WW

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  • Earthfire
    Earthfire Member Posts: 543
    Paper insulation facing

    The paper is a vapor barrier. Rule of thumb in cold climates the vapor barrier goes to the warmer (inside) side of the wall. Down south the recommendation is barrier to the outside of house to keep the hot moist air out. We usually slash the paper with a razor knife when using it in any interior partitions.That will allow any vapour to pass thru.
  • Floyd_5
    Floyd_5 Member Posts: 418
    Did you try the upsell?????

    I'm finding that many times, when given the oppurtunity and given the advantages of the upsell you can have the customer putting in a system the will pay them back many times over.
    I'm finding that it is easier than I thought to sell the "premium" systems. Of course the natural gas prices are helping....

    Floyd
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