GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Audio Play Icon Headphones Icon Plus Icon Minus Icon Check Icon Print Icon Picture icon Single Arrow Icon Double Arrow Icon Hamburger Icon TV Icon Close Icon Sorted Hamburger/Search Icon

Community and Q&A

Best practices for stucco or fiber cement on ICF?

Tripta86 | Posted in General Questions on

We are building an ICF home in Zone 1, on the gulf coast. A beachfront home – very hot, very humid, very salty.

I see a lot of information on waterproofing etc. for ICFs below-grade (we don’t do basements here), but the information on above-grade is a lot more sparse and conflicting. I want to be certain I am using the best building practices for my home.

What would be the best construction method for attaching siding or stucco (or EIFS?) to ICF? Is a drainage gap required? A waterproofing layer, like a peel and stick?

Likewise, is there a clear “winner” between stucco, EIFS, or fiber cement plank siding for ICF? (Brick is not an option for the neighborhood.)

I appreciate all advice!

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.

Replies

  1. User avatar Expert Member
    Armando Cobo | | #1

    Not all products are created equal. You need to download the installation instruction for any and all products you plan to install so you can make the best decision. With all these products, you need to pay attention to moisture management for each induvidual product as well.

  2. Jamie B | | #2

    If its above grade, I suggest you follow the same practice for water management of siding that Martin lays out on here.

    Some ICF come designed specifically so plastic webs can be screwed into, like studs. you'd have to find out their weight capacity to best make a decision on load of your siding.

    On my current build, the ICF portion of my foundation wall will be 3' above grade. I plan to add a WRB, screw in vented furring strips and Hardie Board siding like I am with the rest of the house. This leaves a bulk water drainage plane to grade and adequate venting for drying.

  3. User avatar GBA Editor
    Martin Holladay | | #3

    Tripta,
    Attached is a Word document from an ICF manucaturer (Fox Blocks) showing that manufacturer's advice for manufactured stone veneer. I imagine that details for stucco will be similar, but you need to check with your ICF manufacturer for advice.

    When it comes to EIFS, the EIFS contractor (who needs to be certified) is responsible for the details. This arrangement is required by insurance policies. Owner-builders usually can't install their own EIFS. You have to contract with a certified EIFS installer.

    .

  4. Andrew Bater | | #4

    Much to the dismay of my family, I have no residential construction experience in hot, humid and seashore climate areas! (I have managed some large commercial projects down south.) However, I too found the situation with information on how to deal with above grade ICFs "sparse and conflicting", so I thought would chime in.

    Up here in Pennsylvania I ended up going with a cement board stucco system on our ICF foundation: https://www.basf.com/us/en/products-and-industries/General-Business-Topics/acrocrete-eifs-stucco/wall-systems/cement-board-stucco.html

    This seemed to be the most robust solution and also allowed us to match the synthetic stucco with other non-ICF foundation/wall areas. I grabbed a quick picture this afternoon to show the "stack up".

    From top down:

    A. Hardie board installed using a rainscreen system
    B. Rainscreen vent area
    C. Upper flashing set in a kerf that was cut into the ICFs to the concrete layer (insect barrier).
    D. Cement board stucco, installed on top of a mesh rainscreen that was applied to the ICFs.
    E. Flashing/kickout
    F. Truexterior trim board at grade.
    -1. Designed to be somewhat easily removable for inspection of the ICFs (insects).
    -2. Paint can be retouched if it gets nicked.
    -3. Keeps the stucco/cement-board away from ground moisture.
    G. Platon dimpled membrane extending below grade.

    How we handled insect worries may be the most extensible element of what we did here.

  5. User avatar GBA Editor
    Martin Holladay | | #5

    Andrew,
    Thanks for your comments. Indeed, that looks like a robust, well-installed system.

Log in or create an account to post an answer.

Community

Recent Questions and Replies

  • |
  • |
  • |
  • |