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Re: Granite Cladding (without mechanical fasteners)

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Brent R. Koch wrote:
> 
> Kasey,
> 
> If you have access to a 1994 or 1997 UBC, code provisions can be found in
> chapter 14 for both adhered and anchored veneers. BTW, what model Code is
> used in Vancouver?
> 
> Here's a few paraphrased excerpts for adhered veneers:
> 
> -If your 3/4" (19mm) granite panels weigh more than 15 psf (73.2 kg/m^2) you
> may not use an adhesive installation.
> 
> -In addition to its own weight, the veneer and its attachments are to be
> designed for a minimum horizontal force equal to twice its weight.
> 
> They (ICBO) also include this small and innocent statement, "Consideration
> shall be given for differential movement of supports, including that caused
> by temperature changes, shrinkage, creep and deflection."
> 
> What this means to me is that even after everything "calcs out" at least a
> few of those suckers will eventually pop off the structure for a variety of
> reasons. Ouch!  I would hate to be the guy that is hit by a heavy chunk of
> stone falling from up to four storys.  I would equally hate to be the guy
> who designed the anchorage.  And while I hold such concern here in
> California, it probably holds even more credence in Vancouver where I expect
> the anchorage to be subject to a more extreme performance demand.
> 
> Let me do this ....  Tommorrow I'll be spending the morning at a project
> called the Buck Center in Novato, CA.  This four story concrete building is
> being clad with about $3M worth of Italian travertine panels sized at about
> 2'-6" x 2'-6" (installed with mechanical anchors). The subcontractor
> performing this work, Superior Tile, is the same who installed the cladding
> on the Getty Center in Los Angeles. Let me solicit the opinion of Superior's
> project manager and superintendent as they are very knowledgeable. I'll try
> and post their comments by tommorrow afternoon.
> 
> On your part, I think it would be foolish not to consult with cladding
> companies in the Vancouver area for their input as to how stone veneers are
> applied and how various methods perform.
> 
> Other questions your post brings to mind:
> 
> 1) Your oringinal post states that "the contractor prefers to install them
> by adhesive agent (without using mechanical fasteners) directly on the
> exposed concrete."  Down here stone cladding work is usually performed by a
> specialty subcontractor. Project specs typically require the subcontractor
> to submit complete shop drawings showing the layout and details of
> attachement with stamped calcs.
> 
> 2) Don't the project specifications address the method of cladding
> attachement? Wouldn't any variance be subject to the approval of the
> Engineer, Architect, and Owner.
> 
> 3) Is an adhesive installation compatible with the waterproofing system?
> 
> 4) How does the contractor propose to control the appearance of the
> installation? Mechanical stone anchors have adjustment to accomodate the
> imperfect finished surface of CIP concrete.
> More than likely, an adhesive installation will require a lot of bushing and
> grinding to plane the backing surface.
> 
> 5) Will the supplier and installer provide the same guarantee/warranty for
> an adhered installation as for an anchored one?
> 
> 6) Does using an adhered stone change the overall veneer thickness
> anticipated in the detailing of window and door heads/mullions/sills?
> 
> Hey .... I've rambled for too long. Hope this helps and Good Luck.
> 
> Regards,
> 
> Brent Koch, P.E.
> 
> ----------------------------------------------------------------------------
> -------------------------
> 
> >We don't use adhesive for granite cladding in California, period. I
> >think you should design some steel inserts in the concrete and attached
> >to the connectors of the granite.  If I were you, I would not let the
> >contractor do what he think or use to do his way.
> >
> >Tom Chiu, SE
> >
> >K. Hemmatyar wrote:
> >>
> >> Tom:
> >>
> >> Building Code of Canada 'classification Vancouver's specifications are as
> >> follows:
> >> Seismic Zone = 4
> >> Za (acceleration related seismic zone) = Zv (velocity related seismic
> zone)
> >> = 4.0
> >> v = 0.20 (zonal velocity ration)
> >>
> >> I spoke to one of the colleagues here. He said similar applications have
> >> been done.
> >> However the issue is the appropriate installation method and adhesive
> agent.
> >> The problem with temperature expansion also effects in long run.
> >> I need the information about the "proven" installation procedure.
> >>
> >> Thanks
> >> Kasey Hemmatyar, P. Eng. (structural)
> >> ___________________________________________________________________
> >> >Tom Chiu wrote:
> >> >
> >> >I doubt that adhesive agent for granites is applicable in earthquake
> >> >countries.  Isn't Vancouver Zone 2 or 3?
> >> >
> >> >Good luck,
> >> >Tom Chiu, SE
> >> >
> >> ___________________________________________________________________
> >>
> >> >>K. Hemmatyar wrote:
> >> >>
> >> >> I am presently working on a project which involves the design of
> >> >> installation method of Granite Cladding on a new 4 storey concrete
> frame
> >> >> building. The Granites are 18"x18"x3/4" and the contractor prefers to
> >> >> install them by adhesive agent (without using mechanical fasteners)
> directly
> >> >> on the exposed concrete.
> >> >> If you have some recommendations, please advise.
> >> >> Thanks in Advance
> 
Interesting that the adhesive discussion is occurring at the same time
as the inspection discussion.  Proper material preparation (both
concrete and stone) and proper mixing and application is essential where
adhesion is involved.  For that reason alone, I would not want to rely
upon adhesive materials, alone, to attach 3/4" stone.