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Neoprene vs. EPDM sill sealer?

Grey Wolf| Posted inGreen Products and Materialson

I’ve been looking comparing the two types of rubber to use for sill sealer. Everyone seems to recommend EPDM gaskets from Conservation Technology. All I need is a flat tool (without the raised edges that Conservation Technology offers).

Are there any drawbacks to neoprene?

Where are some other places to buy?

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Replies

  1. GBA Editor
    Martin Holladay||#1

    Grey Wolf,
    Conservation Technology's EPDM sill seal is a quality product. I haven't used a neoprene sill seal, but I imagine it will work.

    In many cases, it's helpful to caulk the crack between the mudsill and the foundation after the framing work is complete (since the framing adds weight that compresses the sill seal). Combining sill seal and caulk is a belt-and-suspenders approach.

    -- Martin Holladay

  2. Grey Wolf||#2

    Thanks Martin. What do you think about high performance tape, instead of caulk over the crack? I've been told this is best practice. Although, I'm sure opinions vary!

  3. GBA Editor
    Martin Holladay||#3

    Grey Wolf,
    It sounded from your original question that you were pinching pennies. Why else would you avoid EPDM sill seal?

    If you have a decent budget, Siga Wigluv tape is an excellent way to seal the crack between your mudsill and your foundation.

    -- Martin Holladay

  4. Grey Wolf||#4

    My post was primarily because EPDM will take too long to arrive AND I don't think the air seal edges are needed since I will be using tape. Neoprene I can buy today.

    The primary reason for using them is for a thermal break between metal and wood.

    I was planning on using pro clima tescon because it is more vapor open.

    According to your tape test, seems to stick as well? But just is easier to rip?

  5. GBA Editor
    Martin Holladay||#5

    Grey Wolf,
    You are overthinking this. It sounds like you want to tape the crack between your steel trailer and the first wooden components of your tiny house. If that's what you are doing, why does the vapor permeance of the tape even matter?

    The point of the tape is to seal air leaks. It's not as if your steel components are vapor-permeable -- so why does the tape have to be?

    -- Martin Holladay

  6. Grey Wolf||#6

    For the rest of the plywood seams, I would favor a more vapor open to facilitate better drying. For the bottom plate, yea good point.

    I am purchasing a package from Pro Clima, so will have the Tescon Vana tape. Planning on using that unless there is any reason not to.

    1. Paul McGeehan||#7

      What if the exterior WRB like Blueskin vp100 SA is run down past the rim joist/plate and adhered to the concrete or icf ? do we need to worry how air tight the sill gasket is?

      1. Expert Member
        Malcolm Taylor||#8

        Paul,

        if your air-barrier is at the sheathing, and you can effectively seal it to the concrete foundation wall, all you need is a sill-sealer to isolate the concrete from the wood sill above.

        1. 删除d||#9

          删除d

  7. Ian Ayers||#10

    嗨,我只是为考虑添加更新的意European SIGA tape to seal the sill to concrete on exterior side. I spoke to someone at SIGA, and they now recommends their FENTRIM F tape for this purpose over WIGLUV. It comes in 6" and 9" widths, with split tape which is nice. They first sold it in black color (has a felt texture on the face), but now it appears like the updated it to grey color, which will blend in nicely with concrete if it is visible below the first course of siding/skirt. (though it's not rated for any UV exposure) I applied Fentrim about 1.5 years ago very close to the ground and nowhere has the tape edge even slightly pulled away from the concrete nor wood (Zip or PT depending how I lapped it). Seems like a great product.

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