Waterproofing is something you’ve got to get right the first time. That’s the mantra of John D’Annunzio, president of Paragon Roofing Technology, who has been a building consultant for more than 25 years. “The cost of repairing a waterproofing issue after the building is completed is almost always extremely expensive and time consuming — especially when you compare it to the cost of initially applying waterproofing materials in a new construction project,” he said.
D’Annunzio has investigated a lot of waterproofing failures over the years, and he points to three key factors:
- Poor workmanship. “The vast majority of problems I’ve seen are due to application errors,” he said. “The most common trouble spots are at details and penetrations.”
- Lack of oversight. “Often theses errors aren’t caught because the installations aren’t being adequately inspected,” he said. “Unlike other phases of construction — roofing, for example — we don’t see enough oversight when it comes to waterproofing applications.”
- Inadequate design details. “Manufacturers often do not provide specific details for every type of application, leaving designers to rely on general language in the documents, which can be subject to misinterpretation.”
In many cases, D’Annunzio’s failure investigations determined the waterproofing materials were never even applied. “This is all too common in below-grade applications that are completed in stages,” he said. “The wall applicator, waterproofing applicator and backfill applicator have to be in sync, or you might end up with a section of wall that is backfilled before it is waterproofed.”
These types of application errors might not be the fault of the designer, but that won’t be apparent when the water begins pouring through the basement walls. The key is preventing these types of problems in the first place. “It’s in everyone’s interest to make sure all the parties are communicating and that the work is completed in accordance with the design requirements,” D’Annunzio said.
For more of my interview with John D’Annunzio, click here to listen to our podcast.