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Roofing Nails Puncture Gas Lines in Texas

Flexible corrugated stainless-steel gas tubing — or CSST — has been popular with U.S. plumbing contractors for well over a decade because it’s light and easier to work with than traditional black iron gas pipe. (Unlike black iron, which is rigidly secured to the framing, CSST is minimally attached, allowing it to withstand earthquakes and — in theory — to move laterally when struck by a protruding nail.) But despite its excellent safety record, the tubing has building officials in the north Texas community of Mansfield scratching their heads over at least a dozen incidents in which it’s been punctured by roofing nails.

According to Mansfield building official Paul Coker, the problem first surfaced last spring, after a severe hailstorm led to thousands of roof replacements. Reports of leaking gas lines began coming in, including one in the home of a city-council member; that line was found to have been punctured in four places.

On investigation, Coker’s department determined that the punctures occurred most often in homes with vaulted ceilings insulated from below with fiberglass batts. Gas lines that had been installed with the required clearance to the roof deck were pushed tight to the deck by the pressure of the batts, leaving them exposed to damage from protruding roofing nails — especially when unnecessarily long nails were used.

Coker says building inspectors hadn’t detected the potential problem earlier because the department’s standard practice has been to inspect mechanical, electrical, and plumbing systems in conjunction with the framing inspection. “Once builders have that green tag, they can insulate and apply the Sheetrock,” he says. The first sign of trouble after a reroofing is the smell of gas, usually reported by the homeowner.

For now, the Mansfield building department is doing its best to make roofers and homeowners aware of the possibility of punctured gas lines. “We’re not trying to point fingers,” Coker says. Meanwhile, local builders seem to be cutting back on their use of CSST. “It was the big product to use when those houses were built,” he notes. “Now that things have slowed way down, we’re mostly seeing black iron again.” — Jon Vara


Hot Countertops Rattle Kitchen and Bath Industry

No builder old enough to remember the last radon scare — which peaked in the mid-80s — wants another one, but the issue may be re-emerging. This time the problem isn’t well water or bedrock under foundations; it’s granite countertops.

Cooking up a crisis. On July 24 the New York Times ran a story headlined “What’s Lurking In Your Countertop?” It told of a New Jersey pediatrician who ripped out the granite countertops in her vacation home after a radon-mitigation technician discovered elevated levels of the radioactive gas in the air during a routine inspection and traced it to the countertops. According to the article, tests of countertop samples performed at Houston’s Rice University found that dozens emitted radon at higher-than-background levels; a few gave off more than 100 times the background level of radon. A laboratory spokesman quoted in the story noted that although not all granite is dangerous, “I’ve seen a few that might heat up your Cheerios a little.”

Most experts agree that homeowners have little to fear from whatever slight radiation exposure they might get from their countertops. In the Times story, David J. Brenner, director of the Center for Radiological Research at Columbia University, described the risk of contracting cancer from a countertop emitting radiation as “on the order of one in a million.”

Just the same, the article has provoked some anxiety in kitchen and bath showrooms around the country. For now, at least, the industry seems to be saying as little as possible in hopes that the issue blows over on its own. The Marble Institute of America (MIA), for example — which represents the natural-stone industry — refuses to answer any media queries about the subject directly, instead referring questioners to the Chicago public relations firm Cohn-Wolfe. Jim Martinez, a spokesman for the firm, concedes that “there’s anecdotal information that people in showrooms are expressing concern,” but suggests the issue is being kept alive by manufacturers of synthetic stone countertops.

The National Kitchen and Bath Association (NKBA) is also keeping mum; it directs questioners to the MIA.

Common sense. Oddly enough, however, the NKBA seems to have tossed its own members a hot potato by recommending on its Web site that consumers consult an NKBA-certified designer before remodeling a kitchen or bath, on the grounds that certified designers “are experts in design who have been taught the proper methods for eliminating radon and other hazardous gases from the home, as discussed in the NKBA Professional Resource Library volume Kitchen and Bath Systems.

Susan Serra, a veteran NKBA-certified kitchen designer in Northport, Long Island, says she was surprised to learn that the association considers her to be well-versed in “eliminating radon and other hazardous gases from the home” despite her complete lack of formal training on the subject.

“What I keyed in on immediately was the word ‘eliminating,’” Serra says. “I know very little about radon, but from what I do know, it’s something you try to control and minimize, not eliminate.”

So far, says Serra, the Times story has led one client to postpone a final choice of countertop material, but otherwise she has not seen any indication that consumers are backing away from stone in substantial numbers.

“I’m not going to pretend to have all the answers,” Serra says. “As a professional, you have to maintain a certain common-sense caution. I make clients aware that there’s an issue and let them make up their own minds.” — J.V.


Dustup Over Drywall

In late July, in a story titled “New Ergonomics Standard Calls for Three-Foot Drywall,” NAHB’s online newsletter Nation’s Building News heaped scorn on a recently published ANSI standard. Describing the voluntary standard (ANSI/ASSE A10.40-2007, Reduction of Musculoskeletal Problems in Construction) as “vague,” “ineffective,” “unworkable,” and “useless,” the article singled out one section in particular, characterizing it as suggesting that employers “ease a worker’s carrying loads by cutting drywall into 3-foot pieces — a size that doesn’t fit on studs that are 16 inches apart, which is the framing dimension used by nearly all architects, designers, and builders.”

Incredible! Could the ANSI committee really have suggested that builders ease drywall handling by cutting off — and presumably discarding — 25 percent of each sheet? The on-center spacing issue, of course, wouldn’t seem to make much difference for board cut lengthwise and applied perpendicular to the framing — but think of all the 8-foot butt joints! Only a team of overeducated researchers in white lab coats could possibly have come up with that one. Or so readers must have thought.

As it turns out, the standard does not in fact suggest cutting drywall into 3-foot pieces. The only mention of “3-foot drywall” is found in Appendix B (which is not actually part of the approved standard), where it’s listed along with such items as lightweight concrete block, fiberglass ladders, and 47-pound sacks of cement under the heading “Examples of Potential Solutions for Reduction of Musculoskeletal Problems in Construction.” And it appeared there, according to A10.40 committee member Scott Schneider, because of a Finnish study that examined worker responses to 900mm “ergo” drywall — which is slightly less than 36 inches wide — and to 1,200mm board. As one would expect, the Finnish drywallers found the narrow board much lighter and easier to work with.

So does that make 3-foot drywall a “potential solution,” as the appendix would have it? Well, with the average age of workers in the U.S. building trades creeping higher with each passing year, it might be kind of nice if building materials kept pace by growing proportionally lighter. Maybe the Finns are on to something. — J.V.