Windows, Doors & Safety Glazing
~12 min read · Identify failed seals, sill defects, and every location where safety glass is required.
Windows and doors are engineered holes in the wall — inspected for water management outside, operation and seals in the middle, and safety glazing where people can fall or walk into glass. Fogged panes and missing tempered marks are the everyday findings.
Water management
Every opening interrupts the drainage plane: look for head flashing above, sound sills sloped to shed (rot probes at sill horns and bottom corners of trim), intact glazing putty on old single-panes, and functioning weep holes on storm windows and vinyl frames (bottom-of-frame slots that must stay open). Stains below the interior corners of a window mark a flashing or sill failure above.
- Head flashing above, sloped sound sill below
- Frame weeps stay open
- Probe sills and lower corners; match interior stains
Operation and seals
Operate a representative sample: full travel, latching, locks, sash cords/balances (sashes that guillotine down are a finding), egress-path windows that actually open. Insulated glass units that have lost their seal show fogging or condensation BETWEEN panes — failed IGU, a replace-the-glass finding, distinct from surface condensation (a humidity note). Check door alignment (diagnostic of movement when new), thresholds, and weatherstripping.
- Operate a sample; note stuck, falling, or painted-shut sashes
- Between-pane fog = failed seal; surface fog = humidity
- Racked doors and drifting margins can flag structural movement
Safety glazing
Tempered (safety) glass breaks into pebbles instead of daggers and is expected in hazardous locations — the enduring principle: glass in and beside doors, glass close to floors and walking surfaces, glazing at tubs/showers and around stairs. The permanent etched 'bug' in a corner identifies it. The precise location list is code-cycle territory — the inspector's framing: glazing in a hazardous location without a visible safety mark is reported for evaluation/upgrading, as a safety enhancement rather than a code citation.
Worked example
In one afternoon: a picture window's lower interior corners show brown staining and the drywall is soft; a patio slider's glass sits full-height beside the walking path with no corner etch; and half the bedroom windows fog up in the morning sun — the fog is between the panes. Sort the findings.
The stained corners: water is getting past the head flashing or sill above — probe, then report active intrusion at the window perimeter with flashing/sill repair and concealed-damage caution. The slider: full-height glazing at a walking surface is a classic hazardous location; no visible safety-glazing mark → report as a safety item for evaluation — struck by a falling person, annealed glass becomes daggers (frame it as safety, not code enforcement). The fogging: BETWEEN panes means the insulated units' seals have failed — moisture-laden air now enters the cavity; the glass units (not necessarily the windows) need replacement; note which units by location. Water, safety, seals — the three lanes of this system's findings.
Common exam pitfalls
Writing off between-pane fog as 'needs better ventilation.'
Ventilation cures surface condensation; fog INSIDE the unit is a failed seal — glass replacement.
Citing the tempered-glazing location list by heart.
The hazardous-location list shifts by code cycle — report unmarked glass in fall/walk zones as a safety evaluation item.
Operating only the windows that look easy.
Sample across the house — including the egress-critical bedrooms, where a painted-shut sash is a life-safety note.
Flash the top, slope the sill, open the weeps; fog inside is a dead seal; pebbles, not daggers, where people meet glass.
Recap
- Openings need head flashing, sound sloped sills, open weeps
- Between-pane fog = failed IGU; surface fog = humidity
- Operate a representative sample; bedroom windows must open
- Racking doors can indicate movement
- Safety glazing (etched bug) expected in fall/walk hazard zones
- Frame glazing findings as safety evaluations
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