When cabinets, shelving units, and other storage units inadvertently detach from walls, the force of the unit and its contents falling to the ground can cause significant injury and property damage.
In this article, Architect & Premises Safety Expert, Ronald Fermano details the requirements for the safe installation and anchoring of wall-mounted units, and discusses the most common failure mode.
Falling Cabinets, Shelves, and Wall Units - Expert Article
The experts in the Premises Safety group at Robson Forensic have investigated numerous incidents where a cabinet or shelf fell from the wall it was mounted to and injured someone. In the majority of cases, the unit was inadequately or improperly anchored to the wall.
The appropriate choice of anchorage and screws needed to properly install a wall-mounted storage unit depends upon the type of wall (drywall, plaster, brick, etc.), the anticipated weight of the contents, and the configuration of the unit being installed. Industry standards provide guidance on safe installation methods. There are industry publications that specifically address the installation of woodwork, applicable to various types of cabinetry.
Possible clues of impending failure
If a cabinet falls after being installed for a period of time, there will sometimes be physical signs of impending failure. These may include:
- Visible sagging or shifting of the cabinet’s position
- Pulling away from the wall, or an appearance of tilting forward
- Deformation of the cabinet surrounding the fastener head
- Drywall dust or particles falling beneath where the cabinet is attached to the wall
Once noticed or following a maintenance request, repair should be initiated in a timely fashion to prevent potential injury or damages caused by the cabinet detaching and falling from the wall. As the following case example will demonstrate, however, there are not always signs of impending failure, making it critical that such fixtures be installed correctly with adequate anchorage.
A wall mounted cabinet fell off the wall and struck the plaintiff, who was sitting at her desk beneath the cabinet. Robson Forensic was retained to determine why the cabinet fell, and whether the manner in which it had been installed was a cause of the incident.
The wall was metal stud frame construction finished with drywall, with two cabinets installed side by side. Each cabinet had an enclosed back. These cabinets were affixed only to the wall; not screwed to one another or to any other base cabinets, and were used to store folders and various office supplies.
Conditions had been changed by the time of our investigation, so photographs taken the day of the incident were used for the analysis. In this case, the fasteners told the story of the installation. For example, the following were indications that the cabinet had not been anchored correctly:
- On the top right corner of the wall area there was drywall tear out (large misshaped hole) caused by the winged anchor pulling through the gypsum.
- There were two bare bolts protruding from the back of the cabinet, indicating that the bolts had not properly engaged with the anchors in the wall cavity.
- The bottom right corner of the wall area contained an elongated hole in the drywall corresponding with a bent fastener on the rear of the cabinet.
The failure of the wall hung cabinet was initiated when the top right wing anchor tore through the gypsum board. Because only 2 of the 6 mounting bolts were properly engaged, the cabinet was caused to rotate about the bottom right anchor. The bottom right anchor bent under the rotational force of the cabinet and its contents, ultimately pulling from its anchor and creating an elongated hole in the wall.
As a result of deficient installation, the impending failure would have been apparent to no one other than the individuals who performed the installation. The wall cabinet was not properly fastened to the wall studs, and the anchors used did not reliably interlock with the wall system to provide proper anchorage. Had the appropriate anchors been installed and fastened to the structural wall framing as industry standards required, the wall cabinet would not have fallen in this manner and the plaintiff would not have been injured.
PREMISES SAFETY INVESTIGATIONS
The premises safety team at Robson Forensic investigates matters involving the design, construction, operation, and maintenance of commercial, institutional, and residential premises. We conduct site inspections, perform tests, and review applicable standards to learn facts and form opinions about how and why individuals were injured within the built environment.
For more information, submit an inquiry or contact the author of this article.
Architecture, Construction & Premises Safety Expert
Ron Fermano is a Licensed Architect with over 20 years experience designing buildings, and performing hands-on construction. He is an expert in Codes and Standards, Construction and Pedestrian Safety. Ron is a registered Architect in New Jersey, Pennsylvania, Delaware and Maryland and is certified by the National Council of Architectural Registration Boards. Ron’s diversified background includes design and construction experience for a wide array of building types including commercial and medical offices, retail strip malls, restaurants, bars/night clubs, private residences, and multifamily housing. He has particular expertise in the evaluation of existing and historic structures.