Decra Roofing [RE-wrenches]

[Matt Lafferty]

===========================================================
Give Your Team Access to Their PCs from Anywhere. Increase 
productivity with a secure remote-access solution from 
GoToMyPC Pro. Stay in touch with your office. FREE TRIAL:
http://click.topica.com/caab6awbz8Qcsbz9JC9a/ ExpertCity
===========================================================

Wrenches  (Mo, read this before you give 'em a bid!):

Regarding using PV on Metal "Tile-Look" Roofing Products in general... Good
Luck!  (For all the reasons brought up by others already and more!)  My
recommendation is to politely decline and refer the Owner to your worst
enemy for service!  Then set up a lawn chair across the street and watch
what happens!

My only exceptions to this are if the original roof is completely stripped
and sheathed with solid ply / OSB and if you get to install the standoffs
(Fast Jacks work as well as anything) before the roof goes on and the roofer
installs all the base and top flashings (two-piece flashings used on most of
these systems).  

I've been involved with two such PV installs, against my adamant
protestations.  NOT fun!  Thank goodness "the higher-ups" got the message
after only two!  (Battle scars galore!)

There are quite a few manufacturers of such products and at least hundreds
of different Installers for each.  The Installation manuals allow for
application over numerous surface types.  You don't know from just looking
what's "underneath"!  Don't rely on the Owner's memory.  I've seen these
over plywood / OSB sheathing, shakes, comp, and even drywall on top of comp!
Sometimes they sheath the substrate with plywood or OSB.  Some of them have
felt over the top of whatever is "down there" and some don't.

When it comes to Cal-Pac, I won't even consider touching the roof in any
way.  I walk on the other side of the street when I see one.  In my
neighborhood, that requires zig-zagging when I walk to the store.  Tbis
product is what I call "The Tin Can Roof"... It is the bottom of the barrel
in terms of quality in my experience (Long before I ever even heard of PV,
by the way).  This roof doesn't just "dent", it tears when you walk on it
wrong.  Dropping a screwdriver on it?  Might as well install a skylight in
that spot.

Up here in NoCal, this company has been in quite a few MEGA Lawsuits over
their products and installations.  They have come and gone through
bankruptcy a few times, each time emerging with "new owners" that "bought
the assets".  I guess the $$$ is so danged good it's too hard to pass up for
somebody with less than honorable ethics.  Fortunately, the trained eye can
spot a Cal-Pac roof from the street as different from other, much better,
systems.  Clue: Hips, Ridges, Valleys.

Other systems, Gerard Stone Coated Steel for one example, are much better in
terms of quality and ability to work with them.  They still dent, and you
can visibly see "paths" in the texture where you walked back and forth
during an installation, though.  These roofing systems are intended for
applications where, "Once you put it on, you never have to go back on the
roof."  They don't like traffic!  If properly installed, I believe they are
good and durable roofs for their intended purpose.

Some considerations for the Bold (Please send me pictures when done...
Close-ups preferred):

Grounding (or not) the entire roof gets to be another issue.  

You may be able to get around bonding the roof if the standoffs, racking,
and conduit are dielectrically isolated from the roof.  One way to
accomplish this is to use Oatey's as the top flashing and make sure the base
flashing is insulated from the standoffs.  You might have to sell it to an
Inspector, but I believe it's a saleable solution. 

The little anodized aluminum nails used to attach the roof to the fur strips
doesn't constitute a solidly grounded connection so you are left to
mechanically bond each piece of the danged thing at least in the area of the
array.  Your local Inspector might require the whole roof to be bonded....
OUCH!  Find out BEFORE you bid on it.  Based on recent and spreading "I
heard this in John Wiles' class" Inspector experiences being had all over
the place up here in NoCal, who freakin' knows????  (No offense to John
intended in any way.  I personally appreciate all he has contributed over
the years... It's not just "what you say or how you say it"... It's "what
they heard"... Which you can only control to a certain point.)  I just had
to straighten out another Inspector over the phone at 7 O'Clock this
morning.  I tried to fax him some doughnuts but my machine got all sticky.
Coming soon to an area near you!  

(Module Manufacturers!!!!!  Where are our "ground it anywhere on the frame"
kits????????)))))  Like, YESTERDAY and for many years now!!!!!!)

If you must bond, it gets to be Ugly & Expensive.  The coating on the "tile"
is a virtual dielectric barrier and has to be removed at each attachment
point, for starters.  Now you've removed the weather-proof coating from
somebody else's product and exposed it to the elements.  How long before
electrolysis sets in?  It's a lot of work, but the creative and patient soul
can install the grounding beneath the roof surface.  For a hundred bucks
I'll draw ya a picture... LOL

Make sure you find out exactly what touch-up paint the roofer uses and get
some for yourself.  If the roofer has / uses touch-up spray glue and
"mineral sprinkles" for areas that the coating gets worn off, get some of
that from him, too.  (Remember, the Owner bought this stuff 'cause it lasts
for at least 50 years and it looks good, too!)

Protect the roof surface as much as possible from traffic while you're
working on it.  One thing I've used on these and other roofs (really good on
hot comp!) is 12" wide strips of 7/16" OSB (rough side up) with re-bonded
carpet padding (rough side down) glued and stapled to the back.  Padding
side down.  These things last for years and are good to just keep in your
shop or garage for when you need them.  They don't take up much space and
are cheap to build.  They also show your customers that you care about their
roof and you will find far less scarring and scuffing on your jobs when
you're done.

Don't touch it at all unless the original roof is completely stripped and
has solid ply / OSB sheathing underlayment!  If you decide otherwise, please
read the following...  

In a previous life, I worked on a few dozen of these roofs.  Skylights, leak
repair (almost always flashing problems), attic venting, HVAC repair, and so
on.  One of my closest friends is a roofing expert, and I do mean Expert.
Inspections, Industry Expert Witness, Etc.  We have worked together on and
discussed all of these systems and pretty much every kind there is over the
years.  In doing so, I've learned much.  Let's put it this way: He just had
his own home re-roofed.  Comp.  Nothing better than good Comp!

In every case I remember, once I took off a few sections, separation between
the bottom of the furring strips and the substrate was very obvious (like up
to 3/4") even if it was installed over virgin solid sheathing.  In each of
these cases, the roof surface appeared to be "nice and straight" from the
ground.  A roof structure settles and flexes differently than the the
dual-flanged roof surface which is attached to the fur strips.  The strength
of the surface material as a system, is greater than the random nails used
to attach the fur strips to whatever they are on top of... I call them "air
nails".  They stay on the roof because the system works as an entire
"system" and the nails holding the fur strips "down" are so long they don't
fully disengage from the substrate.  This is all part of the design and
engineering.  A "floating" system, if you will.

As brought up by others, finding the rafters between the 2x2 furring strips
that are randomly nailed over the top of unknown underlayment makes for a
less than fun day on the roof.  DO NOT believe you can use the furring
strips as solid mounting!  (This was one of the "other" methods referred to
in the next paragraph)

I don't see using U-Bent Hanger Bolts to "grab" or "clamp" rafters as really
suitable for these roofs.  When this method was brought up by a now defunct
"PV Contractor", my bosses thought that was the answer...  The guy even
brought in the Structural Engineer who had "calc'd" it out and approved it.
To this day I don't trust anything that guy stamps.  When I drew it up on
the board in front of everybody, showing "real-world" relationships, the
bosses immediately nixed it, along with two other "bracket" methods they had
brought in.  Even in their "never turned a wrench in my life" existence,
they could see it.  The "Contractor" didn't buy it (Stupid SOB that he is...
I'm being nice, Michael!!!) and it was funny watching his own SE agreeing
with what I said and trying to explain it to him!  One of those little
memories that still makes me smile when I think about it!

Basically, the reason I say this is, your compression nut and washer system
will have to be located under the roof surface and is not serviceable.  Due
to the "unknown" underlayment, you have unreliable compression over time.
Something that was tight ten minutes ago, may not be so solid now... Just
walking across and loading the roof with glass causes deflection which can
start the process before you even leave the site.

We've all witnessed the "roof is stiffer around the array after I bolted it
all together" effect.  On most pitched roofing systems, this isn't
necessarily a bad thing.  In the case of these systems, if you don't use an
attachment and flashing system that provides for leak-free movement between
the surface and the structure, you have effectively defeated the "floating"
element of the roof system's design.  

What WILL happen is this:  Stresses will be applied to the points where
adjacent "floating" sections of roof meet with the "non-floating" sections.
Something's gotta "give".  It won't be "your stuff", you've got it locked
in.  The total stress will be concentrated in a smaller area and seek "the
weakest point".... It's like gas building up in your gut... Sooner or later,
you "burp" from one end or the other.  The roof system needs to be able to
burp, too.  Which end it comes out is anybody's guess!  

If you encounter an existing roof of this type, please, please, think about
this stuff.  I'm not making up a word of it.  (Except the doughnut
fax...LOL)  They can be done properly if you are very attentive to detail,
patient, and understand the dynamics.  Don't think for a minute that "it's
just like a tile roof"!!!!  

Sticky Fax Machines for Everybody!

Matt Lafferty
Universal Energies Institute
mlafferty at universalenergies.com
(916) 422-9772
(916) 628-7694 Cell
(916) 914-2247 Fax
www.universalenergies.com

===========================================================
Let University of Phoenix make 2004 your year. Evening, 
weekend or FlexNet® classes – over 130 locations. Look 
into our programs and get the degree that gets you going!
http://click.topica.com/caab6aBbz8Qcsbz9JC9f/ UOP
===========================================================



- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read

List rules & etiquette: www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com

For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------