GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter X Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Acoustical Sealant for Mud Sill

spakhnyuk1 | Posted in General Questions on

Hi, I have a concrete pour scheduled today for my footings and stem walls (vented crawlspace foundation) and that means I have a framing crew starting the sub floor system early next week.

I plan on air sealing the the mud sill to the stem walls using a combination of sill sealer and acoustical sealant, then using the same approach to seal the bottom plate to my subfloor system. This is a spec house build that will be certified 4 star built green, so the budget is a bit tight.

I have been researching the types of acoustical sealant that’s most commonly used for this application and found the Tremco Acoustical/Curtainwall Sealant, Tremco TremPro JS 773, and Pro Clima Contega HF seem to be the usual suspects.

I have seen a Matt Risinger BUILD show episode where he is using DAP E90 as the acoustical sealant on his bottom plate along with the sill sealer (same approach I’m planning to use.

Does anyone have experience with any of these lower cost acoustical sealant products made by vendors that are available from Home Depot, Lowe’s and Amazon?

I realize the Tremco stuff is likely the best but I would like to save some money if I can get a product that will do the job for my application.

This is a vented crawlspace so mud sill sealant is to minimize air flow into the insulated floor system.

The alternative contenders for sealant are:

Titebond Acoustical Sealant ($7.99 per 28oz tube)
Liquid Nails Acoustical Sealant ($5 per 28oz tube
DAP Soundblock E90 (5.99 per 28oz tube)
OSI SC175 ($5.98 per 28oz tube)

Tremco Acoustical/Curtainwall Sealant ($15 per 28oz tube)
Tremco TremPro JS 773 ($8 per $20oz sausage)

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. beedigs | | #1

    @Slav, what did you end up using for this detail? We have been planning to do the same, use E90, but unfortunately this product is on a long backorder so need to find an alternative. Where were you able to get the E90, or do you have a lot of extras? Also please share sources of where you got the other brands of caulk/sealant. Thanks and I hope you see this soon as we are framing next week.

    1. spakhnyuk1 | | #3

      Hi @beedigs, I ended up using Tremco Acoustical/Curtainwall Sealant. Bought it from a local supplier for like $6-7 a cartridge.

      Sealant Specialists
      Tukwila, WA ยท (206) 624-4574

      All of the other sealants harden. I may experiment more in the future as this was my first build using acoustical sealant for the sills and bottom plates. For my next build I'm also sticking to Tremco.

      Make sure you have a can of Xylene available. This stuff is nasty! I would recommend wearing gloves as the only way to clean it off your hands is with Xylene, and that is an extremely toxic solvent to put on your skin.

      If you decide to try the other sealants, I had success ordering E90, SC175 from, Lowe's and Home Depot. You will have to order online as the big box stores typically don't stock them.

  2. qofmiwok | | #2

    We used Tremco Acoustical and it went great. Readily available.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |