Skip to main content
Add as a preferred source on Google

Five Key Waterproofing Focus Areas

  • 12/01/16

HGA’s Kevin Donaghey offer tips in considering the following specific areas where water can present challenges.

1. Above-grade Walls
It’s important to acknowledge that most exterior materials will take on rainwater at some point over the life of the building, and that an exit route for this water should always be accounted for in exterior wall assemblies. Rainwater should be viewed not as a passive element, but a force actively trying to penetrate the exterior barrier’s lines of defense. Analyzing exterior assemblies through this mindset can help to identify and provide adequate drainage pathways out of a rain-screen system for water that has found its way in.

2. Below-grade Systems
Ground water from surface rainfall or the water table, and its ability to infiltrate large areas of earth and into foundation systems, can be easily underestimated. Diversion of storm water run-off, extensive below-grade drain tile systems, and comprehensive membrane waterproofing at below-grade foundation walls can all serve to keep water out.

3. Roofs
Selecting a roofing system that meets the owner’s criteria for performance and budget can be a challenge, with reduced membrane thickness or warranty coverage being a tempting cost-reduction measure. We encourage the owner to err on the side of caution with roofing selection, even if it means adjusting project scope elsewhere.

4. Windows and/or Skylights
Skylights are typically more horizontally orientated than exterior wall window systems, and thus run a higher risk of water infiltration. Even with adequate slope, it is important that skylight assemblies be equipped with drainage channels, gutters and drop edges to usher rainfall onto the roof, and away from the skylight frame/roofing transition, which typically serves as the most susceptible part of the assembly. This can serve dual purposes (Example: the Language Arts and Humanities Building at East Los Angeles College features sloped skylights at a third-floor courtyard situated over occupied space, which funnel the rainwater into adjacent concrete planter boxes).

5. Doors
Doors located on exterior walls with exposure to the elements will pose increased risk of water infiltration. Drip edges, especially at the horizontal portion frame head, will divert water that would otherwise work its way inward.

This article originally appeared in the issue of .

Featured

  • Can AI Help Build Stronger Communities in Student Housing?

    Student housing success is shifting from operational performance to student experience, with belonging now at the center. A recent 2025 report underscores a growing emphasis on student well-being, community, and engagement, signaling that expectations now extend beyond logistics to ensure students feel supported in their living environments. AI is enabling that shift by reducing administrative workload and giving teams more time to focus on meaningful student engagement.

  • Philadelphia Middle School Facility Earns LEED Gold Certification

    The Alternative Middle Years (AMY) at James Martin Middle School in Philadelphia, Penn., recently received a LEED Gold certification from the U.S. Green Building Council, according to a news release. The School District of Pennsylvania partnered with KSS Architects on the project.

  • Tennessee Middle School Completes Health, Life Safety Renovations

    The Giles County Board of Education in Pulaski, Tenn., recently announced that a series of renovation projects has been completed at Bridgeforth Middle School, according to a news release. The district partnered with Wold Architects & Engineers and Brindley Construction to modernize building systems at one of the district’s oldest schools.

  • Virginia Tech Tops Out New College of Engineering Building

    Virginia Tech in Blacksburg, Va., recently celebrated the topping out of Mitchell Hall, which will soon stand as the largest College of Engineering building on campus, according to a news release. The university partnered with Skanska on the 285,500-square-foot facility, which has an expected completion date of winter 2028.