DSS-E.01.04 — Condensation / Runoff Patterns

Condensation / runoff patterns are appearance changes on glass driven by recurrent water paths (dew, HVAC condensation, building runoff, irrigation overspray) that concentrate dissolved soils/minerals and produce rivulet maps, drip legs, curtains, and edge blooms. With prolonged cycling, very shallow micro-texture may form in preferred paths. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status.

• Vertical “drip legs” emanating from head frames, mullions, signage, or projection elements; fan-shaped curtains from head to sill.
• Rivulet networks that repeat pane-to-pane based on façade geometry; edge blooms where water pools/dwells at gaskets.
• Under raking: sheen discontinuities along flow lines; where cycling is long-term, low-contrast matte within the path.

Surface-catch class (MSRT)

• SC-0 for residue films that lift on reveal.
• SC-1 where incipient micro-texture is present inside flow paths (slight tactile interruption, no chip flanks). SC-2 suggests misclassification-evaluate Ch.03.03 mineral etching or M.02 abrasion if present.
• Perform one light, non-marring pass on a small revealed test patch (substrate). Use polymer stylus if a functional coating is suspected. MSRT supports classification only.

Visual signature

• Continuous flow lines from a discernible origin (head/drip edge/hardware) to sill; branching rivulets that merge/split; repeating geometry across adjacent lites.
• No chip-flank sparkle (not linear scoring); no fused pits/nodules (not hot particle).

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°-120°); use raking to reveal flow edges and matte inside paths. Record distances/angles in-frame.

Location / access

• Record pane ID and surface numbering (#1-#4; laminate-internal). Most common on outboard (#1) faces; interiors (#4) where condensation is recurrent (pools, natatoriums, chilled beams). Between-pane by parallax on #2/#3 → CAT-5 by location.

Mechanism cue (context)

• Roof/facade runoffs, misaligned drips, sprinkler overspray, condensation from HVAC diffusers, uninsulated frames, or thermal bridges producing interior condensate trails.

Assign CAT by visibility at acceptance geometry and MSRT after a reveal patch. Depth values are indicative-field measurement not required.

• CAT-1 (Benign / non-relief): Clear rivulet/drip pattern comprised of residue only; SC-0; mainly angle/raking visible; lifts on reveal patch. Indicative relief: 0-10 μm (optical film).
• CAT-2 (Light): Persistent flow mapping post-reveal with localized SC-1 (incipient micro-texture from cycling); limited standard-view impact. Indicative relief: ~10-40 μm.
• CAT-3 (Moderate): Wide-area, legible flow curtains at standard distance with consistent SC-1 and low-contrast matte inside paths; indicates long dwell/high frequency. Indicative relief: ~40-120 μm.
• Reclassify when: Distinct white/grey crystalline rims or etched halos dominate → evaluate Ch.03 (mineral deposits/staining/etching); linear swirl/abrasion → M.02 abrasion fields.
• CAT-5 (by condition/location): Between-pane/inaccessible by parallax, integrity indicators, or confirmed functional-coating loss on the surface to be worked → CAT-5.

CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not abrade to “force” a response during classification.

• vs. Hard-water mineral system (Ch.03): Minerals show crystalline rings/rims and can progress to etch; pure runoff mapping may lack crystals and lifts on reveal.
• vs. Detergent/surfactant film (R.04.01): Detergent presents tool-path streaks/iridescence; runoff follows gravity paths from a structural origin with no wipe geometry.
• vs. Atmospheric corrosion matte (E.01.02): Atmospheric matte is global/non-directional; runoff patterns are directional with clear origins and branching trails.
• vs. Kitchen/HVAC films (R.04.03/04): Those show oily/tacky veils and wetting anomalies; runoff is flow-path specific and often coincident with drip edges or sprinkler arcs.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; raking macros of flow edges/matte fields; context frames of origins (head/drip edge/sprinkler/diffuser) and multiple adjacent lites to show repeatability. Record distance/angle in-frame.
• MSRT result (substrate): After a small reveal test patch, perform one light, non-marring pass; record SC-class (SC-0/SC-1/SC-2).
• Forms: Pane ID; product family & surface numbering; worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist; photos attached.
• Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e when the worked surface is a factory functional coating.

• E.01.04 Condensation / Runoff Patterns - Directional rivulet/drip mapping from [origin: head frame / sprinkler / diffuser / hardware] on surface #___; post-reveal test patch shows [SC-0/SC-1]; visible at [12/36/72 in] under VIS geometry. Morphology: flow lines, curtains, edge blooms; no chip-flank sparkle, no pits. Classification: CAT-[1/2/3] by visibility and SC-class; reclassify to Ch.03 if crystalline rims/etch halos dominate; CAT-5 if between-pane or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.