Posted - 20 December 2002 10:47
I noticed, as I jumped down the 'Technology Inventory'
list on the PATH web site that the only technologies
that rate a 'Quality' check mark are those materials
that the builders still need to piece together on the
job site; namely engineered framing lumber and steel
Wouldn't you consider SIPs to be high quality and
deserving of a check mark? As a SIP manufacturer, I
know that the quality of our ICBO/BOCA/SSBCCI
approved, PFS/TECO inspected SIPs are of a very high
quality. In fact, I think you'll find that most
builders who use SIPs find them to be very high
quality. Sometimes the accuracy can be too good
('cause the concrete foundation and / or the framed
floor system are not usually to print and the panels
are.....). SIPs are inherently square and plumb.
Additionally, I disagree with the following statements:
"SIPs cannot be used for corners other than 90 degrees
"They are not usually used for ceiling height greater
than 8 feet."
"SIPs may work better for wall construction than for
roofs. Because the panels are heavy, roof installation
can be complicated. Roof design loads are higher than
walls and floors which reduces the allowable
unsupported roof span. "
Precision Panel (as well as other panel manufacturers)
do bay window walls with SIPs on almost every home we
build (it's the style....jpeg pictures available upon
request.) Additionally, we build many homes with wall
heights greater than 8 feet. Quite a few of the homes
we build (entirely) were ordered initially due to the
fact that we could 'balloon frame' walls (up to 24'
high, jpeg pictures available upon request) and the
customer is confident that these SIP walls will never
bow, twist or warp.
Roof panels are one of the best uses for SIPs. The
'roof design loads' can be met with SIPs for almost
everything Precision Panel builds. Keep in mind that
we have areas here in Idaho that require minimum live /
dead load capacities of 125+ psf. Some of the SIP roof
panels that we have installed here in the Boise Valley
have been over 22 feet long. We just completed a roof
system in the mountains that required design loads for
the roof panels of 200 psf.(jpeg pictures available
Some of the side benefits of using roof panels are:
1. Dramatic interior vault.
2. Structure, insulation and nailbase in one
3. Venting of roof panels not required (therefore, a
cleaner roof line).
4. Very energy efficient roof/ceiling insulation.
Since most builders use a crane for their PE trusses,
most feel that the crane cost is essentially a wash
when they are setting roof panels instead of trusses.
If builders feel that roof panels are complicated to
install, I believe this is the fault of the SIP
manufacturer. There is a learning curve (about 2 hours)
to setting roof panels and the SIP manufacturer should
provide on-site consultation and / or assistance in my
"SIPs materials are more expensive than wood frame
Yes, SIPs materials are more expensive. However, a
large portion of this cost can be offset by
accelerating on-site construction times. If panels
arrive on the job site literally ready-to-assemble, the
exterior wall framing can be completed in a fraction of
the time. Precision Panel installed Floor SIPs and
Wall SIPs on (2) 1536 Sqaure Foot homes in Colorado
between 9:00 am and 4:00 pm on November 13, 1998. This
isn't possible with framing........
"Electric installation for SIPs homes may be more
costly than for stick-built homes."
If electricians struggle with wiring panel homes, then
wire chases aren't properly installed in the panels or,
again, the SIP manufacturer hasn't provided assistance.
The learning curve is about 30 minutes, and the
electrician needs to know how to operate a typical
router. Most electricians will find that a typical
house using SIPs for just the exterior walls is very
simple, as long as vertical wire chases are installed
in the panels. If they are, then the electrical can be
run through the trusses and dropped down through the
top plates into the walls and out the pre-routed box
"Because SIPs create airtight construction, whole-house
mechanical ventilation may be necessary."
Airtight construction is somewhat of a mixed blessing.
Although a fully panelized home (SIP floors, walls and
roof for example) is very airtight, the mechanical air
exchange system give you much more control over the
interior living environment than typical stick frame
air infiltration will. In addition, the HVAC system of
a SIP home should be down-sized to allow the system to
cycle on and off at regular intervals (this will help
keep the interior environment from becoming stale). On
the upside, the inherent energy efficiency is a plus.
From an "Environmental Performance' stand point, I
believe SIPs should get the PATH check mark. As you
mention in 'Engineered Wood Wall Framing,' SIPs also
utilize fast growing, hybrid-type trees for the OSB
skins, reducing old-growth timber consumption. A fully
panelized home (envelope) can reduce 2x materials by as
much as 70% on a home. Additionally, the Expanded
Polystyrene is recyclable and a more energy efficient
home is friendly to our natural resources.
A PATH check mark can also be argued for 'Durability.'
SIP homes have been around for around 50 years. The
early homes are still standing and in use. A number of
SIP homes manufactured by Premier Building Systems
of Puyallup, Washington, made it through the Kobe,
Japan, earthquake with little or no structural damage,
while other homes around them were rubble. There are
also SIP homes that were left in tact after Hurricane
Andrew blew through the south eastern US.
I hope this information helps. While I was reading
through the PATH web site, it occured to me that the
SIP information seems to be a bit out-dated. Take
another look.... Talk with some builders who are using
panels manufactured by ourselves and any other FULL
service SIP manufacturer. I think you'll be surprised.
Kind Regards, Drew McDaniel
Precision Panel Structures, Inc.
208 - 939 - 2610 Phone
208 - 939 - 9905 Fax