GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter 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

Brickmold door install with ZIP sheathing and Prosoco / ZIP Liquid

Chris_in_NC | Posted in General Questions on

I’ve been having trouble finding any detail for a brickmould door install when the R.O. is flashed with Prosoco or Zip Liquid Flash.

When the R.O. is flashed with tape, I’ve seen people apply sealant to the rear of the brickmould, and slap the brickmould against the sheathing, then caulk the brickmould transition to the ZIP sheathing.  Apply flashing tape over the head, etc.
I know this method will work with the liquid flashing as well, but I’m a little shaky about water management that relies on properly caulking pieces of applied trim (brickmould).  Is there a better method, or is it fine to rely on the brickmould seal and the fully-flashed R.O. to drain to the exterior?

I’ve also seen details (for tape-flashed R.O.) that remove the brickmould, and use tape to flash between the flat sheathing plane and the jam edge, then reinstall the brickmould over the tape.  Or apply liner-ed flashing tape to the jamb sides, which come from behind the brickmould and tie to the sheathing.
I’m not sure if the tape methods apply for liquid flashing, as applying tape over liquid flashing doesn’t seem to be supported by the product manufacturers.

I’m planning on using the “Door Installation” method from the awesome Hammer & Hand Best Practices manual, with a Prosoco pan with L-metal backdam, and Prosoco on the R.O.  They are missing details that address the door sealing on the exterior side.  Most other liquid flashing resources focus on windows and totally ignore door-specific details.

This is for my workshop with a slab and a double outswing door with aluminum threshold, not a house with a finished floor, etc.
The brickmold is wide and flat, not the more common routed brickmold profile.

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. Expert Member
    Michael Maines | | #2

    "Brickmold" is a specific molding profile; it sounds like you are just talking about flat exterior casing?

    The first thing I do when I get a door with pre-attached casing is remove the casing so I can install it properly. I prefer to order doors without casing. I tape the WRB to the face of the jamb and install the casing over that.

    1. Chris_in_NC | | #3

      Yeah, I think it's just a flat casing. The callout is for "flat brickmold" on the order sheet and jamb spec sticker, oddly. It's not....robustly attached, so it's coming off regardless of integration method.

      I've seen the tape method you mentioned; it's pretty attractive because it's so simple and everything is already in the same plane.

      Do you have any recommendations for tape that is compatible with Prosoco to make that WRB-to-jamb transition?
      Prosoco says there are often compatibility issues with asphaltic materials and butyl adhesives, Huber recommends against flashing tape over their liquid flash, etc., so there are obviously some considerations there, and I just can't find seem to find any info for guidance.

      1. Expert Member
        Michael Maines | | #4

        Manufacturers are often wary about recommending mixing other brands with theirs, especially when chemical reactions are possible. My go-to tape for tricky situations is Siga Fentrim, though it's expensive, it sticks to everything and is vapor permeable which is usually a good thing. 3M 8066 or 8067 are more affordable and impermeable, which is occasionally desirable. All three have acrylic adhesives which are compatible with most materials but require pressure and time to perform properly. I don't use fluid-applied membranes, or at least I haven't yet, so I don't have a go-to detail; I would check with either Prosoco or Huber to see if there are any compatibility concerns with acrylic adhesives in general.

        1. Chris_in_NC | | #6

          I haven't tried Fentrim yet, although it keeps getting mentioned as a problem-solver in a lot of applications, so I should try some.

          I do like 8067, but am not sure if there is a similar "Do Not Recommend" that Huber has for ZIP tape over top of ZIP Liquid Flash.
          Prosoco and Liquid Flash have a similar polymer chemistry, and 8067 and ZIP tape have similar acrylic adhesive chemistry, but I'm just making assumptions based on that....

          Thanks for the tips!

  2. Chris_in_NC | | #5

    I started thinking about this during a coffee break, and it occurred to me that this is conceptually not any different than installing a Euro/flangeless window with a liquid applied flashing. It seems common that the outside is left open (maybe just the exposed spray foam in the gap?) if the air sealing is done on the interior side with tape or AirDam.

    Following that logic, if I'm already planning on using AirDam on the interior, should I just apply the casing and caulk to the WRB, and keep on rolling?

  3. Chris_in_NC | | #7

    As an update, I found out that 3M's commercial flashing tapes (3015 series) have a compatibility table that specifically lists Prosoco R-Guard Fast Flash as compatible for both orderings (3015 adhered to Fast Flash, and Fast Flash adhered to 3015).
    The base chemistry of the 3M 3015 family sounds similar/identical to the 8067 tape, and also to the ZIP tape, so it stands to reason that many acrylic tapes like 8067 should work with Prosoco. 3015 is definitely not as widely available, being a commercial product.

    Whether it's wise to attempt to make a tape stick and seal to an irregular liquid flashed surface is a different matter.

    I'm having fun trying out new products, which is half the point of this workshop project.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |