EIFS joint sealant

Does the joint need to be sealed where the EIFS meet stone walls?

Each and every type or brand of stucco finishing system has a specific set of protocols for handling transitions to dissimilar materials.

Additionally, caulk or sealant is rarely the only prescribed method of water-proofing anything.

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Yes!" All joints where EIFS meets a dissimilar material must be sealed with the appropriate sealant."

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Wherever the insulation system or the EPS boards meet another material, i.e., door/window frame, roof, pipes, meter boxes, exterior faucets,
etc., a minimum 1/2" (13 mm) wide sealant joint must be provided.
To properly install sealant, you need to provide a joint between two
materials. Sealant works like a rubber band or a shock absorber bonded between two surfaces, stretching back and forth as the two surfaces move.
There are two important factors to remember when applying sealant.

  1. The sealant must bond to only two surfaces such as the coated
    EPS board edge and a window frame. It should never bond to
    a third surface such as the substrate. If you bond to the third
    surface, the “rubber band” will not be able to stretch back and
    forth and the sealant will crack.
  2. There must be enough sealant material (minimum 1/2") (13 mm)
    to stretch, yet not too much material (maximum 1") (25 mm).
    There is an easy way to solve both the above problems: use a closed
    cell “backer rod” material sized so that it can be pushed into the joint
    under compression. This will provide a backing to hold the size of the
    joint correctly and provide a third surface that the sealant will NOT
    bond to.
    NOTE: In some cases, the two surfaces to be sealed are not deep enough to
    allow a backer rod to be installed. In such cases “bond breaker” tapes are
    available that may be used in place of a backer rod.
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Hey my BROTHER. Are you located in the STL area? If so can I ask a question? Is there a thermodigital way to find a crack in my chimney or roof? Im stuck at this point. I’ve had tuck pointing done, new roof, new flashing, on chimney I can not find this crack to fix the problem and now it is to the point that my foundation is destroyed.

I would have flashed between the two materials, especially if the stone protrudes out further than the stucco. Keep the drain plane open.

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Image of EIFS/DRYVIT and stone wall for joint orientation. But to answer your question, yes.

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How do we know? If it is EIFS with a drain plane it would certainly drain above the stone as in my diagram. If you seal it, all water will be captured behind the EIFS.

So @tvogt2 do you have a photo? Do you know what type of sheathing is behind the EIFS or is it CMU block?

Drain plane flashing is a sealant.

It is the opposite of a sealant. The last thing we want is for a drain plane is to be water tight.

Sealant defined: material used for sealing something so as to make it airtight or watertight.

Sealants are generally used as a barrier or a means of protection.

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I’m in Florida.


Drainage planes are water repellent materials (building paper, house wrap, sheet membranes, etc) that are located behind the cladding and are designed and constructed to drain water that passes through the cladding. They are interconnected with flashings, window and door openings, and other penetrations of the building enclosure to provide drainage of water to the exterior of the building. The materials that form the drainage plane overlap each other shingle fashion or are sealed so that water drains down and out of the wall. The drainage plane is also referred to as the “water-resistive barrier” or WRB.

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WAFI alert


The Drainage Plane Flashing Battle Continues