Forensics, windows and you, a leaky science
I will guess that the connotation of the word “forensics” in the title causes you to have an immediate negative reaction. But I implore you to read on because we at Architectural Testing Inc. of York, Pa., intend to help manufacturers and contract glaziers start the pendulum swinging the other way with regard to wall-leakage problems. Let’s start by establishing a general definition of the various categories of in-situ testing:
• The first category may be defined as quality-assurance testing. This typically requires nothing more than a pass-fail determination related to the project specification and is often associated with initial product installation.
• Investigative field tests become necessary to isolate a source of leakage, in turn, helping to identify the trade or contractor responsible for the resolution.
• Forensic testing takes the field-testing process to another level, requiring a more intimate knowledge of project documents, design concept or service history to develop a hypothesis for the water intrusion and provide a sound basis for potential corrective action.
These field water tests involve the application of a known quantity of water—equivalent to 8 inches of rain per hour—while simulating a desired wind velocity by establishing an equivalent static pressure differential across the wall or product being tested.
Over many years, ATI has performed thousands of these field tests and currently conducts an average of eight or more daily. These tests frequently produce evidence of water leakage through the wall system.
Most of the water leakage that appears around or near windows does not come through the windows as typically suggested by inexperienced consultants, technicians and engineers. A high percentage of water penetration comes around the window through an improperly flashed, sealed or caulked joint between the windows and the walls. Further, masonry and stucco walls and components have the propensity to leak or wick water through them; this water generally and eventually manifests itself at or near a window or door opening. It is not uncommon for roof leakage to travel down a rafter to the wall and then down the wall until it is deposited at or near the window.
The ability to isolate the specific source of water penetration is critical to the window manufacturer and requires experienced, accredited testing laboratories, properly calibrated equipment, and qualified technicians and consultants.
Through the consensus process, the American Architectural Manufacturers Association of Schaumburg, Ill., has taken the lead to make formal a Voluntary Guide for Forensic Field Testing of Fenestration Products. This guide is an important companion document to ASTM International’s ASTM E2128 Standard Guide for Evaluating Water Leakage of Building Walls. You should consider getting involved as AAMA members study this valuable document.
Protect yourself
I find that most window manufacturers willingly fix any window-leakage problem if given the opportunity within the warranty period. If window leakage is isolated as truly the problem, an easily accessible sill-to-jamb joint is probably the cause and is generally easily fixed. However, too often, the first time that the manufacturer hears about the problem is upon receipt of a lawsuit where the company will be named as a defendant.
Fortunately, many states now recognize this abuse of our legal system and have passed legislation requiring a notice for the opportunity to repair, or NOR, be afforded to the window manufacturer. Understand the NOR legislation in your states of distribution. You, the manufacturer; must get involved in passing NOR legislation in states where it does not currently exist (see sidebar).
Let’s now add a few words of caution. Too often, the building owner doesn’t even want to fix the problem; instead the owner sues everyone in anticipation of obtaining a financial settlement from each defendant, whereupon he pockets a tidy sum. Perhaps the owner will spend a small percentage for a Band-Aid fix until he unloads the property.
On those occasions when corrective action will be taken, a consultant hired by the owner often has a blank check to cover an extreme makeover at the expense of others. Too often, the window manufacturer will be the only man standing with deep pockets, as the subcontractors are out of business and the general contractor incorporated a separate business entity for this specific project only.
For projects with water leakage:
• Determine if your state has enacted NOR legislation. If not, get it passed
• Identify and isolate the specific problem early, whether wall, joint or window
• After specific identification of the problem, accept your share of the responsibility
• Determine if the plaintiff just wants a financial settlement or wants to fix the problem
• Use a consultant or laboratory with recognized credentials, experience and knowledge
• Tie your warranty to the use of certified installers such as InstallationMasters; certified installers have proven their worth throughout the country.
As members of the legal system continue to look for sources of revenue, they often create a problem to fund their dreams. Because of the demand for the investigation of leaks and other on-site testing, my company has recently formed a Forensics Department managed by Engineer John Runkle. He and other professional engineers and experts can help identify and isolate problems with building envelopes. Their mission will be to provide professional and technical assistance to the window manufacturing industry against unjust and frivolous lawsuits.

