James J. Shields, P.E., Mechanical Engineer ::::
Case Synopsis – A housing development company began a large multi-dwelling housing construction project at a site in Southeastern Pennsylvania. The development company hired a General Contractor to design and construct the site along with the erection of hundreds of homes. The project was planned by the development company to require several years for completion. As a first step in the process, the General Contractor obtained a building permit and produced a set of overall design drawings for the entire site, along with a set of design details for home construction. As is commonly the case, the General Contractor was responsible for the hiring of all sub-contractors. In addition, before commencing the work, all sub-contractors were required to sign a construction agreement with the General Contractor.
Approximately one year after the housing project had begun and certain housing sections had been completed, the housing developer and a prospective homeowner entered into an Agreement of Sale. The homeowner moved into the home about six months after signing the Agreement and lived in the home uneventfully for close to nine years. However, at that time, a severe water leak emerged from behind the drywall in the second-floor master bedroom. The water deluge from the leak was so great that it flowed through the wall, flooding the second story floor and pouring down two floors to the basement before the source of the water leak could be located and isolated. A vertical section of drywall was removed to expose the source of the water, which appeared to be originating from the sprinkler piping, although the exact location of the leak was still unknown. When the sprinkler system valves were shuttered the leak stopped, although, by then the volume of water released had created significant damage. The water was being supplied from the Township Water System, and the shutoff valves were able to isolate the home sprinkler system from the water supply.
When the drywall near the ceiling in the vicinity of the source of the leak was removed, more of the sprinkler piping could be examined more closely and tested. This revealed the exact location of the water leak. A drywall nail, which had been installed by the Drywall Contractor, had punctured the sprinkler piping (See Photo 1). However, the unusual nature of this event was the fact that the nail had rusted and fortuitously sealed the hole in the piping when it was originally tested nine years earlier. Over the years, the nail loosened inside the piping, probably from house settling, and resultant piping movement, revealing the combined sprinkler piping and drywall installation error.
In order to recover the enormous cost of the damages, including the cost of motel living for an extended period, the homeowner hired an attorney and filed suit against the three contractors: General Contractor; sprinkler systems contractor; and drywall contractor. This resulted in a litigation, which lasted nearly 5 years.
Expert Analysis – The General Contractor was responsible for the design of the home and to ensure that various construction specifications and procedures were followed. The sprinkler system contractor and drywall contractor signed a Construction Agreement with the General Contractor. Both sub-contractors certified that their work would comply with the signed agreement, and that the General Contractor was to ensure that the sub-contractors met their obligations.
There were two main issues which resulted in the water flooding event. There were violations by both sub-contractors, as well as a lack of adequate site work inspection and supervision by the General Contractor. The first and main issue dealt with the need for “metal plates” to be installed by the sprinkler system sub-contractor. In the signed agreement, the sprinkler system sub-contractor was supposed to have installed “metal plates” in accordance with NFPA Code Section 13D for Sprinkler Systems (See Photo 2). The plates are used to shield the piping whenever the piping is susceptible to being punctured by the drywall (or other) sub-contractor, as had happened in this case. If the sprinkler systems sub-contractor had properly inspected the work after it had been completed, he might have been able to discover the piping installation error (and install a metal plate) before it became concealed behind the wall by the drywall sub-contractor.
The second issue required the next (in line) installer, in this case the drywall sub-contractor, to report any unsatisfactory condition, which would have prevented him from properly completing his assigned work. Even though the drywall sub-contractor was not originally responsible for the error (i.e. the omission of a metal plate), he would have, nevertheless, been held accountable for the error. In essence, he was supposed to have either reported the deficiency to the General Contractor’s Inspector, the sprinkler piping sub-contractor, or have corrected the error himself before installing the drywall. By signing the Construction Agreement, he had stated that he would not cover up “bad work,” which is what had been done in this case.
The performance of the General Contractor’s Inspectors and Supervisors were also called into question. When the inspection of the sprinkler system was conducted, the Inspector should have taken noticed that a metal plate was missing from the piping penetrations through the wooden studs. The Inspector should have questioned why a metal plate existed for the vertical plumbing piping (shown in Photo 2), but was not installed for the vertical sprinkler piping, about 6 feet inboard of the plumbing piping. Both pipes were run through the same 2” x 4” horizontal double wooden header, but the same construction procedures were not applied for the sprinkler piping as had been applied for the plumbing piping regarding the installation of (protective) metal plates.
Conclusions – The sprinkler piping sub-contractor committed a serious error by not installing a metal plate to protect the sprinkler piping from puncture. This requirement is stated in the Sprinkler Piping Section of NFPA Code 13D, which was called out in the Construction Agreement, agreed to and signed by the sprinkler piping sub-contractor. In addition, after the drywall had been completely removed from the entire wall in the master bedroom, other similar drywall nails were noticed very close to piping penetrations (without metal plates) through the wooden studs but fortunately, these were not close enough to the sprinkler piping to result in punctures. However, this proved that the sprinkler piping sub-contractor consistently omitted the installation of metal plates throughout the project, in strict violation of NFPA Code 13D.
The drywall sub-contractor signed a Construction Agreement not to cover up walls that would hide errors committed by previous sub-contractors. He was supposed to report the deficiency to the sprinkler piping sub-contractor or correct it before proceeding with his work. By not complying with the agreement, and installing drywall over unprotected sprinkler piping, the drywall sub-contractor drove a nail through the sprinkler piping and was directly responsible for the puncture which caused extensive water damage to the property.
The General Contractor failed to communicate properly with sub-contractors’ personnel. The General Contractor was also at fault for failure to ensure that the sub-contractors’ performance adhered to their signed agreements and contractual obligations. If the sprinkler piping had been properly inspected by the General Contractor, it is very possible the error by the sprinkler piping sub-contractor would have been discovered and the accident avoided before the drywall sub-contractor installed the drywall, concealing the error. By not properly inspecting and supervising the work of the sub-contractors, the General Contractor was indirectly responsible for the water damage to the property.
Result – Case settled out of court.
James J. Shields, P.E., Mechanical Engineer with DJS Associates, can be reached via email at experts@forensicDJS.com or via phone at 215-659-2010.