ArmorThane pushes exterior waterproofing as the best defense against wet basements

By AI, Created 9:50 PM UTC, May 21, 2026, /AGP/ – ArmorThane says exterior foundation waterproofing is the only long-term way to keep basement walls dry because it blocks water before it reaches the structure. The company ties that argument to International Residential Code Section R406 and to spray-applied polyurea systems used on new builds and retrofit repairs.

Why it matters: - Basement leaks are often driven by hydrostatic pressure, which pushes groundwater through cracks, joints and porous concrete after rain or snowmelt. - ArmorThane says exterior positive-side waterproofing protects the foundation itself, while interior drainage systems only manage water after it has entered the wall assembly. - The distinction matters for homes in high water table areas and other sites where long-term moisture exposure can damage concrete, masonry and interior finishes.

What happened: - ArmorThane USA Inc. is arguing that exterior foundation waterproofing is the only reliable long-term defense against a wet basement. - The company based that claim on International Residential Code Section R406, which separates dampproofing from waterproofing. - ArmorThane says dampproofing slows water vapor but is not designed to resist water under pressure. - The company says waterproofing is required where a high water table or severe soil-water conditions exist. - ArmorThane also published guidance on exterior foundation waterproofing at the company’s foundation waterproofing page.

The details: - Exterior waterproofing places a membrane on the outside of below-grade foundation walls. - ArmorThane says spray-applied polyurea is best suited for that membrane. - The membrane is applied to a prepared exterior wall at roughly 60 to 80 mils. - Polyurea cures in seconds into a seamless, monolithic film. - The company says that film has no laps, seams or fasteners that could become failure points. - The membrane is flexible and can bridge hairline cracks. - ArmorThane says the coating can accommodate seasonal movement in concrete and masonry as soil and temperature change. - The company says exterior pressure pushes the membrane tighter against the wall instead of peeling it away. - ArmorThane says this makes the system more durable under the same conditions that strain interior coatings. - On new construction, the membrane is sprayed after the walls are formed and cured, then protected with a drain board and proper backfill. - On existing homes, the system can be installed after excavation exposes the wall. - ArmorThane says retrofit jobs are often paired with corrected grading and a functioning perimeter drain. - ArmorThane manufactures coatings and spray equipment in Springfield, Missouri. - The company says it supports a global network of certified applicators. - ArmorThane was founded in 1989 and is headquartered in Springfield, Missouri. - The company’s product portfolio includes HighLine, ArmorLiner, UltraBlast, AquaSafe, SureGrip and ArmorDeck coatings. - ArmorThane also provides coatings, spray equipment, training and technical support. - The company identifies itself as “The Polyurea Professionals.”

Between the lines: - ArmorThane is framing basement waterproofing as a building-envelope issue, not just a drainage problem. - That message favors exterior systems because they address the wall before water enters the structure. - The code reference gives the company’s pitch a technical and regulatory anchor, not just a product claim. - The emphasis on certified applicators suggests installation quality is part of the product’s value proposition.

What’s next: - ArmorThane says exterior waterproofing can be used in both new construction and retrofit work. - The company is directing contractors and homeowners to its online guidance for substrate preparation, membrane thickness and drainage. - Long-term performance will depend on correct installation, site drainage and backfill conditions.

The bottom line: - ArmorThane’s core argument is simple: stop water outside the wall, or keep dealing with basement moisture inside the house.