The historical home at Pine Bend County Park in Port Sheldon Township is used as an event center.
Fourteen people were injured when a portion of a 40-by-50-foot deck collapsed during a gala hosted by North Ottawa Community Health System the evening of June 15.
Ambulances transported two of the injured to the hospital.
They had non-life-threatening injuries, Sheriff Steve Kempker said after the incident.
Emergency crews from several police, fire departments and ambulance services responded to the scene when initial reports called into Central Dispatch were that about 100 people were on the deck when it collapsed.
Kempker said that between 20-30 people were actually on the deck at the time of the incident. The injured people fell about 15 feet to the ground. None of them were seriously injured.
GMB Architecture and Engineering inspected the deck and determined that the laminated veneer lumber used in the structural beams “was the wrong material to use in the outdoor environment of the deck.”
That is because the laminate product is not suitable for the absorption of chemicals used in the pressure treatment process, which would make the wood appropriate for outdoor use.
The architect noted that the design called for twin, laminated beams, 1¾ inches wide by 11¼ inches deep, attached to one another and for the beam to serve as the interior spine of the deck.
The investigation revealed that the interior of the laminated beams at the point of break had significant rotting, whereas the non-laminated lumber, which absorbed the pressure treating chemicals, was not rotted and remained structurally sound.
County officials said that Ottawa County generally does not use the laminated beams in their outdoor decks. Their use this time was unique to the Weaver House design.
The Weaver House was not damaged in the deck collapse and remains open for public use.
The deck area will remain closed to visitors until it can be built without laminated beams.