Custom Residential Architects Network

 View Only

Community HTML

Michigan Loft

Quick Links

Who we are

The Custom Residential Architects Network (CRAN®) Knowledge Community develops knowledge and information to benefit architects who are engaged in, or who are interested in learning more about, custom residential practice. CRAN® presents information and facilitates the exchange of knowledge and expertise to promote the professional development of its members via discussion forums, national symposia and conventions, publications, and local activities.

2024 CRAN® Symposium

September 18-22

The Westin Seattle
1900 5th Avenue 
Seattle, Washington 98101

Registration will open in July 2024.

Sponsorship Opportunities

Download the prospectus for the CRAN forum at AIA24 and the CRAN Symposium sponsorships. 

2023 Symposium

The CRAN® 2023 Symposium was held October 11 - 15. View the schedule for more info>.

Expand all | Collapse all

Continuous Insulation

  • 1.  Continuous Insulation

    Posted 10-15-2019 07:22 AM

    I'm currently working on continuous insulation wall details for a residential design and would prefer to keep the exterior sheathing against the studs for lateral structural design needs. Does anyone have experience with locating the CI on the interior side of the wall - between the studs and gypsum wall board?

     

    J.H. Dickerson, AIA

    Dickerson Architecture

    Monroe, NC

    CRAN March AIAU Course


  • 2.  RE: Continuous Insulation

    Posted 10-16-2019 05:54 PM
    You can install CI on the interior side but I may not recommend it in your climate area. In the NorthEast, where I'm located, we want the vapor barrier on the inside because the inside is going to have higher humidity levels in the winter. However given your in South Carolina, you're in that mixed zone where depending on where in the state you are, you may be more worried with exterior humidity rather interior. Continuous insulation, once taped, provides an adequate vapor barrier and you would not want to install an additional v.p. elsewhere in the wall. IC can also be installed over exterior sheathing however you want to make the outer face of the IC is your drainage plane, which means taping seams and additional detailing at openings to make sure that water cannot get behind the IC and rot the sheathing and create mold & mildew issues. If installing on the inside, there are insulations that have recessed channels to accept furring strips, where you can attach the furring strips through the insulation to the studs behind. If that is what you decide to do, be mindful of light switches and outlets where you have to add additional framing to support the electrical boxes.

    ------------------------------
    Scott Roeber AIA
    Principal
    Hudson Valley Architecture, PLLC
    Saugerties NY
    ------------------------------

    CRAN March AIAU Course


  • 3.  RE: Continuous Insulation

    Posted 10-16-2019 06:24 PM
    Hi John,

    Why not place the CI on the exterior face of the sheathing?  We've done this successfully on several projects.  There are several ways to handle openings in the wall plane, w/o much difficulty.  Take a look at Roxul insulation, they also provide details for this on their website rockwool.com

    ------------------------------
    Gregory Holah, NCARB
    Architect
    HOLAH Design + Architecture
    Portland, Oregon 97232
    ------------------------------

    CRAN March AIAU Course


  • 4.  RE: Continuous Insulation

    Posted 10-16-2019 07:43 PM
    I like to do staggered studs so that there is no thermal break. Prefer it to the detailing of CI on the exterior.

    ------------------------------
    Karen Smuland
    Karen Smuland Architect, Inc
    Bend OR
    ------------------------------

    CRAN March AIAU Course


  • 5.  RE: Continuous Insulation

    Posted 10-16-2019 10:23 PM
    There is a product called R-3 from Zip system that has both sheathing and insulation, AND an ICC number, ESR-3373.

    ------------------------------
    Judith Wasserman AIA
    Bressack & Wasserman
    Palo Alto CA
    ------------------------------

    CRAN March AIAU Course


  • 6.  RE: Continuous Insulation

    Posted 10-17-2019 01:46 PM
    I don't know the regulations specific to North Carolina but, here in California, our Energy Code does allow the continuous insulation to be applied on either side of the wall, or both. It only requires that the assembly meets the required U-value for that climate zone. What I'm more interested in is finding more Eco-friendly alternatives that polystyrene or polyiso. Any suggestions?



    CRAN March AIAU Course


  • 7.  RE: Continuous Insulation

    Posted 10-17-2019 02:12 PM
    AG Atkinson, see my response. Roxul insulation, rockwool.com

    ------------------------------
    Gregory Holah, NCARB
    Architect
    HOLAH Design + Architecture
    Portland, Oregon 97232
    ------------------------------

    CRAN March AIAU Course


  • 8.  RE: Continuous Insulation

    Posted 10-18-2019 07:06 PM
    FRT Cellulose

    ------------------------------
    Stephen Reinel AIA
    Principal
    Reinel Architecture & Design, LLC
    Jacksonville FL
    ------------------------------

    CRAN March AIAU Course


  • 9.  RE: Continuous Insulation

    Posted 10-21-2019 06:34 PM
    I can't seem to find Cellulose in board form for continuous installation methods. Do you know of a manufacturer?



    CRAN March AIAU Course


  • 10.  RE: Continuous Insulation

    Posted 10-22-2019 06:09 PM
    Cellulose is hydrophilic , it absorbs moisture. Continuous insulation is typically outboard the studs and sheathing, where it can be exposed to moisture. Therefore, we use cellulose insulation inside the weather barrier and moisture tolerant products outside the WB.  We recommend mineral wool insulation is a more durable CI. Since insulations could see small amounts of vapor, or even water in any location due to leaks, we provide for 2-directional, or at least 1-direction drying potential for all envelope materials.

    ------------------------------
    Mark Anderson AIA
    AIA, CPHC, President
    Anderson Sustainable Architecture, Inc.
    Saint Paul MN
    ------------------------------

    CRAN March AIAU Course


  • 11.  RE: Continuous Insulation

    Posted 10-19-2019 12:16 AM
    Edited by Steve Hall AIA 10-19-2019 12:58 AM
    Here in NC (for everybody else), code energy requirements have been rolled back to IBC 2009 standards by the home builder lobby. Although their argument has been that better codes degrade "affordable housing," this really just shifts the initial costs of better construction to home owner operational costs in repairs and higher energy bills from being barely code compliant. So-called affordable is actually more expensive beyond the first year or two.

    The other responses here look to have you on the right path. But I recommend you (all architects, frankly) become familiar with the excellent body of building science research relating to these kinds of questions that is accumulating around the web at places like Green Building Advisor, Fine Home Building, Building Science Corporation, Matt Risinger (YouTube), and Energy Vanguard.

    I believe architects should provide better design than is available through the more common avenues. It is low hanging fruit to understand building science and offer its value to the marketplace. Quality is a frequent tagline for most everybody in the industry, but I think we're in the unique position of being able to bring the science to reality and contrast the depressingly low quality of construction typically provided.

    ------------------------------
    Steve Hall, AIA | SteveHallArchitecture.com | Cary NC
    ------------------------------

    CRAN March AIAU Course


  • 12.  RE: Continuous Insulation

    Posted 10-19-2019 12:44 AM
    Hear hear!

    ------------------------------
    Judith Wasserman AIA
    Bressack & Wasserman
    Palo Alto CA
    ------------------------------

    CRAN March AIAU Course