Date | June 16, 2015 |
---|---|
Location | Berkeley, California, U.S. |
Coordinates | 37°52′05.5″N122°16′10.5″W / 37.868194°N 122.269583°W |
Deaths | 7 |
Non-fatal injuries | 6 |
On June 16, 2015, shortly after midnight, five Irish J-1 visa students and one Irish-American died and seven others were injured after a balcony on which they were standing collapsed. [1] The group was celebrating a 21st birthday party in Berkeley, California. The balcony was on the 5th floor of an apartment building at 2020 Kittredge Street in Berkeley, then called Library Gardens. The district attorney of Alameda County launched a criminal probe into the incident. [2] In January 2022, one of the injured died from a stroke related to the injuries. [3]
In June 2015, Mayor Tom Bates of Berkeley promised a wide-ranging investigation into the cause of the accident. The evidence is overwhelming that dry rot from improper construction caused the collapse, not the weight of the 13 students. [4]
This section possibly contains original research .(February 2024) |
Although, as the immediate aftermath photos show, the proximate cause was dry rot, [5] [6] which is caused by excessive moisture intrusion into the supporting wood framing, undermining its structural integrity, the only known investigation report fails to definitively identify the source of moisture, its entry route(s), or the mechanism(s) of its transport. [7] It simply lists 11 "factors which appear to have contributed" without discussion of their relative importance, whether any of the factors was a necessary condition, or which combination of factors were sufficient. The report's format further obfuscates with extensive redactions (some of which are incomplete and thus gratuitous) and by publishing only a poor-quality scan of printouts of the reports. Architect Robert Perry, the author of the as-built vs. as-designed report, focuses exclusively on rainwater entry into the building envelope, and makes observations that appear to be at odds with the evidence. For example, he claims that "dry rot damage [in the collapsed balcony] had occurred along the top of the cantilever balcony deck joists". [8] But the immediate post-collapse photos show that these joists had already disintegrated to the point that they were unidentifiable. Furthermore, he fails to address strong evidence for vapor transport within the building envelope resulting in concealed condensation in the deck's joist cavities. [9] The deck was on the north-facing wall of the building, and has little or no sun exposure for most of the year. The deck joists, made of an engineered wood product known as laminated veneer lumber, were fully enclosed on its exterior surfaces by vapor barrier membranes, yet open to the main building's joist cavities. [10] The deck's joist cavity temperature is dominated by exposure to the outdoor environment, while the interior joist cavity temperature is dominated by the conditioned spaces sandwiched above and below, the latter being warmer most of the time. [11] [12] This configuration causes the deck's joist cavities to condense water vapor supplied by the interior and retain it as liquid, creating optimum conditions for the growth of wood-destroying fungus commonly called dry rot. [13] [14]
Two independent and detailed reviews of the structural design found no deficiencies in the deck's designed load-bearing capacity. As designed and originally built, but absent the dry rot, the deck would have easily supported itself and the 13 people. [7] [10] But with the joists rotted to powder, the only remaining strength was in the ceramic enclosure, which consisted of the unreinforced concrete deck and stucco soffit and walls. The resulting ceramic box beam, devoid of its former LVL joists, and not intended as a structural support, was vulnerable to sudden, brittle failure without warning.
Pre-collapse exterior views of the collapsed fifth-floor balcony and the identical fourth-floor balcony are available in Google Street View. [15]
Six people died in the immediate aftermath of the collapse. They were identified as 22-year-old Ashley Donohoe, and Olivia Burke, Eoghan Culligan, Niccolai "Nick" Schuster, Lorcán Miller and Eimear Walsh, all aged 21. All six were Irish and from Dublin. [16] On 2 January 2022, survivor Aoife Beary died of a stroke, the consequence of injuries sustained in the collapse. [3]
Alameda County prosecutors opened up an investigation in the accident on June 25. They stated that involuntary manslaughter charges could be filed. [17] On that day, District Attorney Nancy O'Malley denied that pressure from the Irish community led to the collapse inquiry. On July 3, 2015, the Alameda County Superior Court rejected a restraining order bid by Segue Builders, a construction company, against the examination of evidence. O'Malley had argued the granting of a restraining order would interfere with her duty to investigate the tragedy. [18]
On September 18th, 2018, a law was signed requiring inspection of a 15% sampling of exterior load-bearing structures with wooden supports on apartment buildings every 6 years. [19]
A joint funeral service for Olivia Burke and her cousin Ashley Donohoe took place on June 20, four days after the collapse, in a church in Cotati, California. Funeral services were held in Dublin for the other victims. [20]
In December 2015 a court was told that the collapse happened because contractors cut corners to save costs and that the management company for the building, Greystar Real Estate Partners, ignored a "red flag" when students who rented the apartment complained about mushrooms growing on the balcony. Legal cases by some of the victims were set to be combined and heard together. By the end of 2017 it was reported that most of the lawsuits had been settled. [21] [22]
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to liquid water when in contact with a liquid or solid surface or cloud condensation nuclei within the atmosphere. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition.
Lumber is wood that has been processed into uniform and useful sizes, including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing. Lumber has many uses beyond home building. Lumber is referred to as timber in the United Kingdom, Europe, Australia, and New Zealand, while in other parts of the world the term timber refers specifically to unprocessed wood fiber, such as cut logs or standing trees that have yet to be cut.
Thomas H. Bates was the 21st mayor of Berkeley, California, and a member of the California State Assembly. Bates is married to Loni Hancock, another former mayor of Berkeley and State Assembly member who served in the California State Senate. He is a graduate of the University of California, Berkeley and was a member of the Golden Bears' 1959 Rose Bowl team. Bates was a captain in the United States Army Reserves after graduating from college and served in Germany. He worked in real estate before serving on the Alameda County Board of Supervisors and in the state legislature.
Glued laminated timber, commonly referred to as glulam, is a type of structural engineered wood product constituted by layers of dimensional lumber bonded together with durable, moisture-resistant structural adhesives so that all of the grain runs parallel to the longitudinal axis. In North America, the material providing the laminations is termed laminating stock or lamstock.
Laminated veneer lumber (LVL) is an engineered wood product that uses multiple layers of thin wood assembled with adhesives. It is typically used for headers, beams, rimboard, and edge-forming material. LVL offers several advantages over typical milled lumber: Made in a factory under controlled specifications, it is stronger, straighter, and more uniform. Due to its composite nature, it is much less likely than conventional lumber to warp, twist, bow, or shrink. LVL is a type of structural composite lumber, comparable to glued laminated timber (glulam) but with a higher allowable stress. A high performance more sustainable alternative to lumber, Laminated Veneer Lumber (LVL) beams, headers and columns are used in structural applications to carry heavy loads with minimum weight.
Dry rot is wood decay caused by one of several species of fungi that digest parts of wood which give it strength and stiffness. It was previously used to describe any decay of cured wood in ships and buildings by a fungus which resulted in a darkly colored deteriorated and cracked condition.
Waterproofing is the process of making an object, person or structure waterproof or water-resistant so that it remains relatively unaffected by water or resisting the ingress of water under specified conditions. Such items may be used in wet environments or underwater to specified depths.
A vapor barrier is any material used for damp proofing, typically a plastic or foil sheet, that resists diffusion of moisture through the wall, floor, ceiling, or roof assemblies of buildings and of packaging to prevent interstitial condensation. Technically, many of these materials are only vapor retarders as they have varying degrees of permeability.
Wood drying reduces the moisture content of wood before its use. When the drying is done in a kiln, the product is known as kiln-dried timber or lumber, whereas air drying is the more traditional method.
Building insulation materials are the building materials that form the thermal envelope of a building or otherwise reduce heat transfer.
Porch collapse or balcony collapse is a phenomenon typically associated with older or poorly constructed multi-storey apartment buildings that have wooden porch extensions on the front or rear of the building. The collapses have a number of causes, including overloading due to excessive weight from overoccupancy. Overoccupancy can result from guests filling a porch at a party, from people seeking cooler breezes during a heat wave, or from people filling a porch while seeking shelter from the rain. It may be from the weight of furniture/appliances, wading pools, or air conditioner compressors. After years of rain and snow, it may be from rotted wood, soil subsidence under the porch foundation, rust of nails and fasteners, and not being built to specifications required by modern-day building codes. Many older porches were built before codes required them to be able to support a legally mandated load of so many pounds per square foot or metre, and porches are often not as sturdily built as interior structures. The phenomenon is associated with older or poorly constructed multistorey apartment buildings with wooden porches. Architect Stanley Tigerman said that in New York City one finds steel fire escapes, but in Chicago, the distance to alleys behind multistorey brick buildings encouraged the construction of wooden multistorey porches.
Cellulose insulation is plant fiber used in wall and roof cavities to insulate, draught proof and reduce noise. Building insulation in general is low-thermal-conductivity material used to reduce building heat loss and gain and reduce noise transmission.
On June 29, 2003, an overloaded balcony collapsed during a party in a Chicago, Illinois apartment building, killing thirteen people and seriously injuring fifty-seven others. It was the deadliest porch collapse in American history.
Indoor mold or indoor mould, also sometimes referred to as mildew, is a fungal growth that develops on wet materials in interior spaces. Mold is a natural part of the environment and plays an important part in nature by breaking down dead organic matter such as fallen leaves and dead trees; indoors, mold growth should be avoided. Mold reproduces by means of tiny spores. The spores are like seeds, but invisible to the naked eye, that float through the air and deposit on surfaces. When the temperature, moisture, and available nutrient conditions are correct, the spores can form into new mold colonies where they are deposited. There are many types of mold, but all require moisture and a food source for growth.
An engineered wood joist, more commonly known as an I-joist, is a product designed to eliminate problems that occur with conventional wood joists. Invented in 1969, the I-joist is an engineered wood product that has great strength in relation to its size and weight. The biggest notable difference from dimensional lumber is that the I-joist carries heavy loads with less lumber than a dimensional solid wood joist. As of 2005, approximately 50% of all wood light framed floors used I-joists. I-joists were designed to help eliminate typical problems that come with using solid lumber as joists.
A rainscreen is an exterior wall detail where the siding stands off from the moisture-resistant surface of an air/water barrier applied to the sheathing to create a capillary break and to allow drainage and evaporation. The rainscreen is the cladding or siding itself but the term rainscreen implies a system of building. Ideally the rainscreen prevents the wall air/water barrier from getting wet but because of cladding attachments and penetrations water is likely to reach this point, and hence materials are selected to be moisture tolerant and integrated with flashing. In some cases a rainscreen wall is called a pressure-equalized rainscreen wall where the ventilation openings are large enough for the air pressure to nearly equalize on both sides of the rain screen, but this name has been criticized as being redundant and is only useful to scientists and engineers.
Dry rot treatment refers to techniques used to eliminate dry rot fungus and alleviate the damage done by the fungus to human-built wooden structures.
Joseph Lstiburek is a forensic engineer, building investigator, building science consultant, author, speaker and widely known expert on building moisture control, indoor air quality, and retro-fit of existing and historic buildings.
Interstitial condensation is a type of condensation that may occur within an enclosed wall, roof or floor cavity structure, which can create dampening.
The leaky condo crisis, also known as the leaky condo syndrome and rotten condo crisis, is an ongoing construction, financial, and legal crisis in Canada. It primarily involves multi-unit condominium buildings damaged by rainwater infiltration in the Lower Mainland and Vancouver Island regions of coastal British Columbia (B.C.). In B.C. alone an estimated $4 billion in damage has occurred to over 900 buildings and 31,000 individual housing units built between the late 1980s and early 2000s, establishing it as the most extensive and most costly reconstruction of housing stock in Canadian history.