Hard Water Stage Borderline, Restore Now vs Disclaim: Threshold Decision Tree
Why this matters
A residential customer points at a row of windows facing a sprinkler line and asks for them to be cleaned. The crew inspects: there are visible water-spot deposits, the deposits have a tactile profile under a fingernail, and they are clustered in a vertical pattern matching sprinkler overspray. Routine cleaning will not remove these. The decision is whether to quote and execute a hard-water restoration in the same visit, defer to a separately scoped restoration appointment, or disclaim the issue and clean only the panes that benefit from a standard wash.
The wrong call has cost in both directions. Restoring on the spot without a written scope and pricing exposes the company to a scratch claim if anything goes wrong on tempered glass. Disclaiming when the deposit is light enough to lift in a few minutes of work loses both the customer satisfaction and the upsell. This decision tree gives a defensible threshold so the field choice is consistent across crews.
Step 1: Classify the deposit stage
Use the standard four-stage classification adopted across the IWCA restoration training material:
- Stage 1 (light): visible only at raking light, no tactile profile under a fingernail. Lifts with a strong detergent solution and gentle agitation. Restoration time per pane: under five minutes.
- Stage 2 (medium): visible at normal viewing distance, no tactile profile, requires a mild acid restorer or fine polish. Restoration time per pane: five to fifteen minutes.
- Stage 3 (heavy): visible at distance, clear tactile profile under a fingernail, requires acid restorer and possibly a polish. Restoration time per pane: fifteen to thirty minutes.
- Stage 4 (etched): the deposit has chemically etched the glass surface. Cannot be restored. The glass must be replaced or the customer accepts the appearance.
Determine the stage with the fingernail test, a raking flashlight, and a misting bottle. Misting wets the deposit; if the deposit still shows when fully wet, it is Stage 3 or 4. If it disappears when wet, it is Stage 1 or 2.
Step 2: Determine glass type
The glass type changes the restoration risk profile substantially.
- Annealed flat glass: tolerates moderate abrasive and acid methods.
- Tempered glass: more prone to scratching from abrasive methods because the heat-soaking process can leave embedded fabrication debris that drags under a razor blade. Always check the corner for a temper stamp before any razor or abrasive work.
- Low-E coated glass: the coating may be on the inside or outside surface. Restorers applied to the coated face can damage the coating. Identify with a coin test (hold a coin near the glass; on a Low-E pane the reflection differs between coated and uncoated panes).
- Insulated glass units with seal failure: restoration cannot fix internal fogging, only the exterior face. Address the IGU as a separate conversation.
Razor-blade restoration on tempered glass is prohibited without confirming temper status and without a written scope and customer sign-off. Embedded fabrication debris from the tempering process can scratch the glass under a blade even when the technique is correct. When in doubt about temper status, use only chemical or abrasive-pad restoration, never a razor.
Step 3: Apply the restore-vs-disclaim threshold
The threshold rule, based on stage and glass type:
- Stage 1 on any glass: restore on the spot if the customer agrees and the time fits the visit. No separate scope is needed; document the work on the invoice as an additional line item.
- Stage 2 on annealed glass: restore on the spot or quote as a same-day add-on. Customer signs the add-on scope before work begins.
- Stage 2 on tempered or coated glass: do not restore on the spot. Quote as a separate scope and schedule a dedicated visit with the appropriate kit and a written waiver.
- Stage 3 on annealed glass: do not restore on the spot. Quote as a separate scope with photos and a written waiver covering the risk of residual marking after restoration.
- Stage 3 on tempered or coated glass: quote as a separate scope, often with a recommendation to contact a glazier for replacement quotes for comparison.
- Stage 4 on any glass: disclaim. Glass cannot be restored. Document the diagnosis with photos and offer to coordinate with a glazier for replacement.
The discipline of this threshold is more important than any individual judgment call in the field. It keeps crews from over-promising on glass conditions they cannot reliably correct.
Step 4: Identify and address the root cause
A hard-water deposit is a symptom. The customer almost certainly has an ongoing source: a sprinkler hitting the glass, a roof drip without a gutter, or a hose-down practice on a deck above the panes. Identify the source and brief the customer. Sprinkler adjustment is the most common fix. Gutter repair addresses roof drip. Hose-down practices can be replaced with a squeegee finish.
Without the source fix, any restoration will be a recurring cost. Customers who understand this will either adjust the source or accept the recurring restoration cost knowingly.
Step 5: Execute the restoration if approved
For approved on-spot restorations (Stage 1 or 2 on annealed glass): mask non-glass surfaces, apply the restorer per manufacturer instructions with dwell time, agitate with a non-abrasive pad in overlapping passes (never a green Scotch pad on glass), rinse thoroughly, and squeegee to a finish. Inspect from inside and outside at standard viewing distance. If residual marking persists, do not chase it on the same visit.
Step 6: Document the decision
Whatever the call, document it on the job card: stage assessment per pane, glass type confirmation, decision (restored, deferred, disclaimed), before-and-after or stage-notation photos, and customer signature on any added-scope work. This protects against later disputes and supports the restoration upsell pipeline.
Step 7: Update the account
If the customer agreed to a deferred restoration, set a follow-up task. If the customer disclaimed and accepted the appearance, note the decision so the next crew does not re-raise the conversation. If the customer wants the source fixed, leave a referral note for trusted partners.
References
- International Window Cleaning Association (IWCA) I-14.1 Standard for Window Cleaning Safety
- ASTM C1036 Standard Specification for Flat Glass
- ASTM C1048 Standard Specification for Heat-Strengthened and Fully Tempered Flat Glass
- OSHA 29 CFR 1910.23 Ladders
- OSHA 29 CFR 1910.28 Duty to have fall protection