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RE: Hardy Frames

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Bill

As Dennis pointed out, the Hardy frame is very rigid compared to the typical plywood wall. If the rigid diaphragm analysis method holds any water, the hardy frame will attract a lot more load than just the tributary load on it.

Gautam


From: "Dennis Wish" <dennis.wish(--nospam--at)verizon.net>
Reply-To: <seaint(--nospam--at)seaint.org>
To: <seaint(--nospam--at)seaint.org>
Subject: RE: Hardy Frames
Date: Thu, 23 Oct 2003 10:03:28 -0700

Bill,
I have used the Hardy Frames (now a company owned by Mitek, Inc.) on
many jobs and while it takes some time to get the builder used to
installing them as the prejudice seems to be more to Simpson's
Strong-wall, the transition in using them is smooth due to their rep's
ability to visit the jobsite and work with the contractor.
The R-value only needs to be adjusted when you get down to their 18"
wide panels (called a Hardy Panel rather than a frame). An R of 4.5 is
indicated on their ICBO report for the panels and an R of 5.5 for their
Frame. However, I tend to design everything where a proprietary
shearwall system is used to an R of 4.5.
The Hardy system is sufficiently stiffer than proprietary plywood walls
and less prone to bastardization in the field (plates destroyed by
electrical runs or plumbing). The one downsize is that they come in only
one thickness - 3 1/2" which is aligned with the exterior face of the
wall to allow the interior to be furred with a flat 2x stud for drywall
adhesion.

The deflection of the frames and panels can not be beaten by any plywood
walls - often taking over 4,000 pounds of shear at 8 to 10 feet with
less than 1/4" of deflection at working stress loads. Installation is
the same as the Strong-wall as there are templates to use and the
connection, depending on loading, is above the 2x mud sill and below the
double 2x top plate. Connection below is by traditional anchor bolts and
the Holddowns are part of the 4X4 12 (or maybe 8) gauge posts at each
side - making the uplift concentric verses conventional eccentric
loading by HD's or PHD's. The older models had to be installed before
the framing to allow inspection of the Holddown mechanism as the opening
in the columns was located adjacent to the wood studs. However, they
changed this in the current models and placed it so that the frame can
be installed without wasting time during framing for an inspection.

The one thing that the engineer is responsible for that is not clear in
any of the proprietary systems is the design of the foundation for
bending due to the higher loads. This is a must, but Hardy has four
pages of general notes and details in DWG format that you can use and
upgrade to the work you do.

I've used these for nearly six years now on about ten or more homes (not
counting the donations Hardy made to our non-profit Building Horizons
Program). Comparing cost, Hardy comes in cheaper when you consider
deflection of the frames, equal when comparing frame for frame (or
slightly more) and a little more when considering training. Once the
framer is up to speed, they generally indicate that they prefer the
Hardy system. There are stock sizes, but they will custom make a frame
given enough time. I also found that they work well with my clients - if
a wrong size is ordered, Hardy will find another job that is willing to
trade out the frame ordered and make the arrangements so as not to slow
down the building timeframe.

Call Hard, talk with David and ask for their package as well as their
video's. They will give you as much as you want in order for you to pass
along to your clients to show them how the system is installed. I am
designing a home right now that does not have sufficient wall area for
conventional shearwalls and have replaced high-load plywood walls with
Hardy Frames.

Dennis S. Wish, PE

-----Original Message-----
From: Bill Allen [mailto:T.W.Allen(--nospam--at)cox.net]
Sent: Thursday, October 23, 2003 9:31 AM
To: seaint(--nospam--at)seaint.org
Subject: Hardy Frames

I am looking for advice from those who have used Hardy frames in
residential construction in high seismic zones (particularly in CA with
the 1997 UBC / 2001 CBC).

I've seen the literature, scanned the ICBO report, but, frankly, I don't
pay attention to things very well until I have to use it on one of my
projects. Well, I did a stoopid thing and mentioned Hardy frames to a
client of mine and he would like to substitute all double sided shear
walls with Hardy frames.

For those of you who have used them, any pitfalls? Anything to watch out
for? Any change in the analysis? To me, they look like OCBFs requiring a
different R, requiring multiplying design forces by 1.5 (or worse,
limited applicability due to AISC Seismic Provisions), etc. but possibly
the ICBO report has avoided all of this.

Input would be most appreciated.

Regards,

T. William (Bill) Allen, S.E. (CA #2607)
V/F (949) 248-8588
San Juan Capistrano, CA
http://members.cox.net/ballense/





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