Col­lapse puts new fo­cus on wood dry rot

Fa­tal bal­cony fail­ure in Berke­ley points to a prob­lem seen in low-rise apart­ments and con­dos for years.

Los Angeles Times - - FRONT PAGE - By Rong-Gong Lin II, Lisa Girion and Paige St. John

BERKE­LEY — The wood rot that many ex­perts be­lieve con­trib­uted to the deadly bal­cony col­lapse here has been a prob­lem in lowrise apart­ment and con­do­minium com­plexes for years.

In­ves­ti­ga­tors on Wed­nes­day were try­ing to de­ter­mine how the wood beams of the bal­cony that failed — killing six peo­ple — had de­te­ri­o­rated so thor­oughly in the eight years since the apart­ment was built.

On Wed­nes­day, they an­nounced that the bal­cony on the f loor be­low was also in dan­ger of col­laps­ing and or­dered it to be re­moved im­me­di­ately.

Out­side engi­neers who vis­ited the site and ex­am­ined pho­to­graphs said there were clear signs that the beams sup­port­ing the deck had rot­ted due to wa­ter ex­po­sure.

“Just eight years? I mean, that’s al­most un­heard of,” said Dar­rick Hom, pres­i­dent of the Struc­tural Engi­neers Assn. of North­ern Cal­i­for­nia. “They need to fig­ure out — I mean, lit­er­ally, was there a river run­ning through here or what?”

Wood con­struc­tion of the bal­conies is com­mon for lowrise residential build­ings. Most of­ten, hor­i­zon­tal beams, or joists, that hold up the f loor in­side the apart­ment sim­ply ex­tend through the ex­te­rior wall to hold up the deck.

The ubiq­uity of these decks makes the deadly col­lapse here early Tues­day that much more un­nerv­ing.

The seven beams hold­ing up the bal­cony on Unit 407 of the fifth f loor of the Li­brary Gar­dens com­plex snapped in an in­stant, spilling 13 latenight revel­ers onto the ground be­low. Most of the vic­tims were stu­dents vis­it­ing from Ire­land, in­clud­ing five of the dead.

The beams should have easily held the weight of that many peo­ple, ex­perts said.

But wood rot, also known as dry rot, can make a beam that ap­pears sturdy por­ous,

enough to crum­ble on con­tact, due to the growth of a fun­gus that feeds on the wood.

Gene St. Onge, an Oak­land civil and struc­tural engi­neer, vis­ited the scene in Berke­ley on Wed­nes­day and said the wa­ter dam­age was clear both on the col­lapsed bal­cony and the one the be­low it that was or­dered dis­man­tled Wed­nes­day.

“You can see ev­i­dence of wa­ter at the front, some stain­ing at the front face of the lower bal­cony,” St. Onge said. “There’s some brown stain­ing in the front.”

There are a va­ri­ety of ways wa­ter could have leaked into the wood joists. “It could’ve been that the door above the bal­cony didn’t have a proper wa­ter­proof seal be­low it,” St. Onge said. “It could’ve been wa­ter com­ing in from the roof down the in­te­rior of the wall. It’s a tricky mat­ter and it takes some in­ves­ti­ga­tion to de­ter­mine where it came from.”

Another pos­si­bil­ity is the lack of f lash­ing un­der­neath the door — a piece of an­gled sheet me­tal that di­verts wa­ter drain­ing down the stucco away from the wall.

In gen­eral, be­fore the stucco layer is ap­plied dur­ing con­struc­tion, wood bal­conies can be wrapped in wa­ter­proof mem­branes — like sticky as­phalt — and then sealed to the wa­ter­proof­ing of the ex­te­rior wall.

Any gaps could al­low wa­ter to seep in.

Nor­mally, there are signs of a wa­ter in­tru­sion, said Taryn Wil­liams, a civil and struc­tural engi­neer in San Fran­cisco, who in­ves­ti­gates struc­tural and wa­ter­proof fail­ures for the com­pany Simp­son Gumertz Heger.

Cracks might ap­pear in the stucco as well as a light­col­ored stain­ing called “eff lores­cence.” But some­times stucco can con­ceal the ex­tent of the wa­ter dam­age in the in­te­rior and make a se­vere prob­lem look mi­nor on the out­side.

The 177-unit apart­ment com­plex was de­vel­oped by Trans­ac­tion Cos., a Berke­ley group, with a Rich­mond­based con­trac­tor, Segue Con­struc­tion Inc. and TCA Ar­chi­tects, which has an of­fice in Oak­land.

Segue Con­struc­tion, the Li­brary Gar­dens’ gen­eral con­trac­tor, was tar­geted in two law­suits over al­leged im­proper wa­ter­proof­ing of bal­conies that led to wood rot, in Mill­brae and San Jose.

Records show Segue paid $3 mil­lion to re­solve the law­suit in San Jose. It paid an ad­di­tional $3.5 mil­lion in the Mill­brae case, said Tom Miller, a lawyer who rep­re­sented the res­i­dents.

Sam Singer, spokesman for Segue, said the lit­i­ga­tion had “no bear­ing on this tragedy” and they in­volved dif­fer­ent types of bal­conies.

“That lit­i­ga­tion, that is com­mon to ma­jor con­struc­tion projects,” he said. “Segue Con­struc­tion has built

more than 6,000 apart­ment units and has never had an in­ci­dent like this.”

A res­i­dent of Li­brary Gar­dens, Rahila Jar­rett, said the roof of her build­ing rou­tinely leaks wa­ter into one of her apart­ment bed­rooms dur­ing rainy sea­sons. “It shorts out the light in the ceil­ing,” she said.

The city of Berke­ley has a rental hous­ing safety pro­gram that re­quires an­nual in­spec­tions of units, cov­er­ing such is­sues as loose handrails, ex­posed wiring or wa­ter leaks.

How­ever, the manda­tory in­spec­tions do not re­quire a re­view of bal­conies or decks. The in­spec­tions also are done by the build­ing owner and not re­quired to be kept on file with the city.

Ten­ants on their own may re­quest an in­spec­tion of a rental unit by the city of­fice of hous­ing code en­force­ment that would in­clude rail­ings and decks.

The city of Berke­ley re­leased a state­ment say­ing “the build­ing was sub­ject to a va­ri­ety of in­spec­tions un­der the build­ing code un­til 2007, when it re­ceived its fi­nal ap­proval. Since then, there have been in­spec­tions by Hous­ing Code En­force­ment and for any ten­ant im­prove­ments.”

There have been other high-pro­file cases of bal­cony fail­ures

A sec­ond-floor bal­cony at a UC Santa Bar­bara fra­ter­nity fell dur­ing a street fes­ti­val cel­e­bra­tion in April 2013, badly in­jur­ing five stu­dents. Some sued, al­leg­ing dry rot con­trib­uted to the col­lapse.

The 1996 col­lapse of a fourth-f loor bal­cony dur­ing a cock­tail party in San Fran­cisco left one woman dead and 14 oth­ers in­jured. Pros­e­cu­tors said the land­lord’s ne­glect of the build­ing was so egre­gious that they brought man­slaugh­ter charges in the case, and a law­suit re­sulted in $12 mil- lion in dam­ages.

Jeff Chiu As­so­ci­ated Press

BRO­KEN ENDS of joists pro­trude from the Li­brary Gar­dens af­ter a bal­cony col­lapsed. Ex­perts won­dered how the wood could rot in only eight years.

Jeff Chiu As­so­ci­ated Press

A FLAG of Ire­land, f low­ers and a sign mark a shrine to the vic­tims of the bal­cony col­lapse, many of whom were stu­dents from Ire­land.

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