By: Joseph Contreras
A disgruntled building resident or occupant has reported an interior leak to the owner or manager of a building. Sometimes maintenance personnel can easily identify the causes of these leaks, such as an open window or missing sealant around a fenestration. Other times, the source can be difficult to pinpoint.
In order to properly identify the cause of a leak, all pertinent information must first be gathered from the building owner, property manager, residents, superintendent, etc. By assessing who noticed the leak, when it was first observed, what was happening at the time of the leak (e.g. wind-driven rain over several hours), where the leak was located, if there were multiple areas of water infiltration and how often it occurs, will help an exterior specialist gain insight into why and how the leak is happening
Faulty exterior conditions are the most common reason for many reported leaks. Determining these sources of water infiltration often requires thorough examination and testing by an experienced professional.
At Sullivan Engineering, we investigate each reported leak and perform exhaustive testing to confirm the point or points of infiltration. Some sources are easily identified, such as a leak in a top floor apartment that is located directly below a roof drain. Others are difficult to determine, and may require days of testing before the infiltration location is accurately pinpointed.
Testing usually involves spraying water at a designated area of a building and monitoring the testing location to determine if water is penetrating the building envelope. Since water always finds its way to the lowest point, it’s important that water testing at a façade or roof be performed methodically. The investigating professional must identify the location of the reported leak, begin by performing water testing at the coinciding area of the building envelope, and move the spray upward as areas of infiltration are ruled out. Systematically moving the spray, and continuously monitoring the building’s interior will eventually allow the water testing specialist to identify the main cause(s) of the reported leak and develop a corrective plan.
Besides hoses, Sullivan Engineering often uses a customized spray bar that’s constructed of PVC pipe and fittings, and is equipped with soft spray nozzles to mimic a slow and steady rain. This spray bar is typically secured and hung from a rooftop and used to spray the building’s façade. Over the duration of the testing, we continuously monitor the affected interior areas, taking moisture readings at selected time increments and recording the results. If an elevated moisture reading is obtained, we can then assume there is a problematic exterior condition at the location of the water testing. Sometimes a deleterious exterior condition can be easily seen, such as a severe step crack in the masonry. Other times, probes must be performed to visually determine deteriorated or failing building components that are the contributing sources of interior water infiltration and damage.
Understanding and fixing the true underlying cause(s) of leaks when they are first reported can save time and money on more extensive future exterior and interior repairs. Therefore, Sullivan Engineering recommends that building owners and managers work closely with an experienced building envelope consultant when leaks require investigation.