When I write about water damage for any publication, we’re usually focused on issues that originate from inside the building envelope. This article will be about the top sources of moisture intrusion we, as restorers, see most often. 

Before we dive into specifics, I think it’s important to make a clear distinction. When it comes to determining the category (or sanitary condition) of the water with outside sources, it’s all about what the water came into contact with before it entered the structure. Any water that has run across the ground before entering a structure would be considered category three (black water) and would require the removal of porous building materials affected by the water. 


1. Roof Leaks - By far and above the most common source we see. Today’s commercial and residential structures are often plagued by a backlog of maintenance projects. When you couple that with the fact that most densely populated areas in Hawaii are in the leeward side of the island, these old roofs don’t have much of an opportunity to shed water on the day to day. With the exception of wind damage, most roof leaks are easily prevented by an annual roof inspection and by repairing or replacing damaged sections of the roof. Most properties would defer temporary repairs opting to wait until reserves permit them to replace the entire roof. From my perspective, this is short sighted. The damage that can be caused by one roof leak is pretty significant and I would always advise to perform the temporary repairs even if the replacement is already scheduled. 

2. Flooding -  As our weather patterns have shifted over the past 20 years, we’re beginning to see more events where streams are overflowing and causing property damage. Unfortunately, these types of losses usually cannot be prevented. The best thing you can do to protect your property in these instances is to secure federal flood insurance if you’re in a registered flood plain. The type of coverage afforded by these programs is different than a normal property or commercial liability policy. Also, make sure storm drains and culverts on the property are kept clean and clear of debris. Any type of flooding is regarded as category three, meaning the quality of the water is regarded as grossly unsanitary. Last year, when East Oahu had massive flooding, we did some water quality testing. Our findings indicated that water from stream flooding contained almost three times the contamination as a normal sewer pipe overflow. 

3. Irrigation - Ever drive by a property when their sprinkler system is on and see one sprinkler spraying water directly at the side of a building? It happens often. These types of losses are easily avoided by simply correcting the spray pattern of the sprinkler. In colder climates, this is a less common problem because most sprinkler systems are serviced at least twice throughout the year. Once to winterize the system to prevent flooding and then again in the spring to get the system back up and running. In Hawaii, these systems operate year around. For most properties, I always recommend making sure there’s someone inspecting the sprinkler system monthly to prevent these types of losses from occurring 

4. Wind Driven Rain - Most common during Kona Storms, we’ll get a lot of calls for wind driven rain. These are usually from buildings with a south or west facing exposure and the point of entry is the sliding patio door. For these, prevention is pretty simple. When severe weather is imminent, just place a water sock or other water barrier device in front of the sliding glass door. We’ve seen instances where this simple step has prevented hundreds of gallons of water from entering the building. Making sure your windows are not beyond their service life is also important. 

“An ounce of prevention is worth a pound of cure.”

For most of these sources, the fixes are remarkably simple and cost effective to prevent the losses from occurring. Having a solid plan in place is always the best way to prevent water from entering or to lessen the damage from water entering your building. 


Article as seen in the November 2019 Building Management Hawaii issue by Anthony Nelson, SVP of Operations for Premier Restoration Hawaii.