More Mold Mania Ahead
To the Editor:
The story "Mold Mania"
(In the News,
1/03) is strange and disturbing. One item that the article
failed to point out, however, was the underlying cause for the
water damage in the claimant's home. Was it a construction
defect, an accident, owner negligence, or something else? How
the insurance industry responds to each of those causes may be
There are no licensing requirements for home builders or home
designers in Texas. As a result, shoddy and inappropriate
construction techniques have become the accepted norm here. For
example, one standard residential construction uses brick
veneer exterior walls on a concrete slab-on-grade. Usually, the
exterior sheathing is OSB without any moisture resistant
membrane. The flashing, if used at all, is typically 6-mil
poly, installed haphazardly at best. I have never witnessed
flashing being used at any lintel condition. I often see a poly
vapor barrier used on the inside of exterior walls, even though
that practice runs counter to the International Energy
Code, which was adopted by the state in September 2001.
Under the code, this region is considered a warm, humid
climate. Because of the tighter construction required by the
code, which drastically changes the rate of drying compared to
the rate of wetting, I predict that Texas hasn't yet seen the
worst of mold-related claims.
James J. White, AIA
Fort Worth, Texas
JLC senior editor Ted Cushman responds: The heart of the
Ballard case was never about mold or construction defects.
Although "toxic mold" (whatever that is) dominated the media
coverage of the case, mold and health issues were not allowed
in the courtroom. Construction defect liability never entered
into it, either. It was a case about homeowner's insurance on
an existing home that Ballard had purchased at a foreclosure
auction, and the builder was never involved. The only part of
the case that survived appeal is the part based on the
insurance company's tardiness in assessing and paying the
original water damage claim for Ballard's oak floor -- a
technical violation of Texas business practices law. Ballard
simply seized the opportunity to profit from a legal
vulnerability that the insurance company had left itself open
to. It's not clear from the record what the original water
source was, but it seems to have been a leaking shower pan. If
there's one lesson for contractors to learn, it's this: Water
and moisture complaints should be addressed promptly -- not
next week, not tomorrow, but today.
Old School Lives On
To the Editor:
I'm writing regarding the article
Options" (1/03). In 1988, I installed Imperial Rib
38-inch-wide by 36-foot-long Galvalume roof panels on my own
home. At the time, I explained to a company engineer that,
given the length of the panels and the different rates of
expansion of wood and steel, it would actually be better to
screw through the 3/4-inch-high ridge rather than in the pan.
This would allow room for the screw to "lean" back and forth
during temperature changes, putting less stress on the screw,
preventing the circumference of the hole from enlarging, and
avoiding distortion of the whole panel, for that matter. That,
plus a local farmer's advice that a hole in a ridge rarely
leaks, while a hole in the pan is a sure leak, put me squarely
in the old school. The engineer said, "Gee, I never thought of
that," and off I went.
Twelve years later, I found a small drip in a heavy rain while
inspecting the attic. On closer inspection, I found many screws
backed out on the south-facing roof panels, probably because I
hadn't used long enough screws. Still, only one leak!
So I got out the climbing gear and replaced all those
backed-out screws with longer ones. And by the way, there was
no elongation of holes, either. So I'm still firmly back in the
old school on exposed-fasteners metal roofing.
Incidentally, screwing through the ridge is much more
forgiving if your screw is off at an angle a bit, since, as
I've pointed out, holes in the ridge rarely leak anyway. Just
look up from under a barn roof that has roofing recycled from
another barn; even with all those holes, there's hardly a leak
in a hard rain.
Your Tax Dollars at Work
To the Editor:
I read with interest your article
Foundations for Expansive Soils" (11/02). I'd like to tell
your readers that the Engineering Properties and Universal
Classifications of Soils is available free to virtually all
U.S. citizens. Visit your county U.S.D.A. Natural Resources
Conservation Service office, which has mapped all soils in the
U.S. and has published a soil survey for each county. Find your
land via legal descriptions or just look at the aerial photos
in the book, then check the keys for your soil type. The
appendix has a chart with the engineering characteristics for
each soil in that county.
It still pays to double-check the soils for a particular site,
but these soil surveys come pretty close to the mark. NRCS
offices can be located in the phone book blue pages under U.S.
Government, Agriculture subheading.
Oklahoma State University Cooperative Extension Service
Tulsa County, Okla.
Strength of Adhesive in Laminated
To the Editor:
The strength of the built-up rafters described in the article
Barrel-Vault Rafters" (12/02) depends to some extent on the
bond of the "construction adhesive" used between the 2x12 core
and the plywood joint scabs. Though the variety of adhesive was
not identified, from the photo it appears to be the type that
is not suitable for use where the joint is under continuous
stress, because this kind of adhesive remains pliable after
curing. Under long-term loading, such nonhardening adhesives
tend to creep and may allow the glued parts to gradually slide
out of position. If the strength of the adhesive was relied
upon by the engineer, it would be important to select a
hardening adhesive rated for continuous loading in a critical
application such as this.
Carl Mezoff, P.E.
Author Mark Lord responds: The engineer who designed the
rafters specified "standard construction adhesive," so we used
the brand that we have had the best results with. Had we been
using only adhesive to bond these materials together, it would
clearly have been of paramount importance to use the correct
structural adhesive, as Mr. Mezoff points out. However, the
engineer's design called for a rigorous schedule of clinched
16-penny nails to do the structural work. The construction
adhesive was very useful for holding the laminated layers in
alignment as we worked.
Another Crown Jig
To the Editor:
Eric Wachsman is right in his observations about drywall
flatness at intersections
12/02). His block will give an accurate mark.
The gauge I use places the molding perfectly and shows where
compromise is necessary. Using the jig, I can also hold the
molding with one hand while nailing it with the other hand. I
generally make the gauge out of 1/2-inch plywood and cut it at
least 12 inches long. You simply cradle the molding in the jig
as you press it to the wall; you don't need to make any marks
on the wall.
As I measure the length for each piece, I start by striking a
"bash block" at each inside corner of the room to make sure the
drywall is tight to the framing and that there is framing there
to support the pressure.
Collins Trim and Remodel
To the Editor:
Joe Stoddard's article on digital cameras
1/03) doesn't mention floppy-disk storage cameras like the Sony
Mavicas. Sure, floppies are "old" technology, but they're
cheap, you can get them anywhere, and the pictures can be read
without a special program. There are tons of cameras out there,
all the way up to and higher than the Nikon D100 my
photographer wife uses, but I'd vote for the Mavicas as being
highly friendly technology in comparison to others.
via e-mailJoe Stoddard responds: I had originally included a section
on Mavicas but dropped it when I edited the article for length.
The upside of Mavicas is that the files are easy to share; real
estate salespeople love them because it's so easy to hand off
the images. On the downside, the 1.44-MB image isn't that
great, plus the cameras are big, bulky, and relatively
expensive. A source at Sony also recently told me that
floppy-disk models are not long for this world; Sony plans to
move everything to CD-R.