Custom Residential Architects Network

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I have a project where the existing exposed 12" CMU foundation walls will be covered with natural veneer stone.  Unfortunately, the floor framing above is cantilevered out over the foundation.  To make things right, I need to get the inside face of the stone about 4" out from the block.  I am considering applying (2) layers of 2" rigid foam to the block using fasteners and mastic prescribed in EFIS (i.e. Dryvit) applications but in lieu of the synthetic stucco, adhere the stone with the use of mesh or cement board.  Has anyone ever attempted this?  I am in Maryland where we have both hot and cold temperatures. 

I thank you for any guidance or suggestions in this non-typical installation..

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John Lehman AIA
Lehman Associates, PC
Highland MD
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How thick is the veneer stone? Also, how tall is the exposed foundation? If it surrounds a crawl space with a shallow footing, you might consider laying thin masonry 'soaps' up from the footing and also tying into the CMU wall, then applying the veneer. Another approach might be to use beefy pressure-treated furring to the CMU, then attaching the cement board. The important aspects are the structural integrity and the moisture resistance. I would not consider the rigid foam substrate as it's not a structural element.

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W. Douglas Gilpin, Jr. FAIA

W. Douglas Gilpin, Jr. FAIA - Architect, PLC
Charlottesville, VA and Block Island, RI
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John
Not clear how mesh or cement board would be used to attach stone veneer? A 4" veneer needs to be anchored structurally to the block wall with steel ties - not seen mesh substituted. Better to leave a 2" air space behind the stone and 2" insulation adhered as you say to the concrete block. That will require 4" ties and that is pushing it, but it has been done. Hopefully there's a way to collect moisture from the air space? 

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Allen E Neyman
Rockville, MD

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Michael Cullen AIA
Elmhurst IL
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John

There are two excellent resources that you can contact for help on this matter.
                  Mr. Brian Trimble
                  Brick Industry Association
                  1850 Centennial Park Drive, Suite 301
                  Reston VA   20191
                  703-674-1535
and
                  Scott Conwell  AIA, CDT, LEED AP BD+C
                  Director of Market Development and Technical Services
                  International Masonry Institute
                  Illinois Area Office
                  2140 Corporate Drive
                  630-396-3144
                  Direct: 630-396-3106
                  Email: sconwell@imiweb.org 

Both of these men are extremely knowledgeable in masonry (brick and stone).    I have been to many seminars that both of these men have conducted.   The IMI has their national headquarters out east probably near where you are.    I would contact either or both for recommendations. 

Good Luck
Michael Cullen  AIA, ALA