08/18/2026
No foundation pour is perfectly flat. Rigid lumber set on top only touches the high spots, while everywhere else is a gap running the whole wall length. Foam sill seal can’t chase every dip.
So before anything else goes down at Observation Row, we apply PROSOCO AirDam directly onto the bare concrete, flowing into every irregularity standard foam would miss.
The bead runs the entire perimeter, not just around the bolts, though every bolt gets its own dedicated seal. AirDam’s STP chemistry stays flexible and can be applied even on damp concrete, so weather delays don’t compromise the seal.
While the AirDam is still uncured, we press the foam sill seal directly into it. Foam alone does real work - moisture retarder, insect barrier, some airflow resistance - but pressing it into wet AirDam actually seals it instead of just sitting on the concrete.
Once the sill seal is set, we run another bead of AirDam on top. Down the centerline, plus every butt joint and termination. Insurance, not redundancy: the first bead sealed the concrete below, this one closes anything that slips through the sill seal or a seam.
Concrete → AirDam → sill seal → AirDam → sill plate. One continuous air barrier before a single stud goes up.
Foundation-to-framing is one of the trickiest junctions in the envelope; and one of the costliest to miss.
See how Observation Row is different in our bio.