Berkeley building inspectors have determined that water seepage and dry rot were to blame for the balcony collapse that took the lives of six young people last week, five of them on J1 visas from Ireland, and injured seven others. However the inspectors' report, perhaps for legal reasons, stopped short of making "a formal causal determination," as the AP reports.

It seems clear, though, that the small balcony gave way under the weight of 13 people when the two main wooden support joists broke off, and photos of them showed signs of mold and rot. The joists were made of an engineered, laminate wood product common in such beams, but which are especially prone to falling apart if exposed to water. Atop these joists was a sheet of OSB (oriented strand board), and a two-inch layer of concrete.

The Chronicle had several experts examine the photos of the scene, where the city of Berkeley quickly moved to remove the second balcony below the one that collapsed, noting that membranes meant to create a water seal around the beams appeared to be punctured, possibly during construction. Also, one forensic building inspector explains that the "flaked" strands of wood that make up such engineered products "because it’s a wood fiber material, it wants to go back to its original shape... We’ve seen laminated strand lumber decaying in less than three years."

It appears likely that the Berkeley City Council will change the building code now to require other materials, like steel or pressure-treated wood, to support balconies.

The building at 2020 Kittredge Street was only seven years old, and the construction firm that built it has already faced litigation in similar cases involving compromised balconies, paying $6.5 million in recent years to settle two cases.

The Alameda County district attorney's office issued a statement late Tuesday saying they would be "looking into this matter."

So far no criminal or civil charges have been filed.

Meanwhile, a GoFundMe campaign has started to help the families of the thirteen victims with expenses related to their travel here, etc.

Previous coverage of the Berkeley balcony collapse.