A clean bead line and intact glass label are not a glazing-system inspection: support, edge clearance, gasket continuity, drainage and material compatibility must be checked at the stages when they remain observable.
A completed window looks uniform from both sides. The glass marking matches the schedule and the beads appear seated. Yet nobody recorded which blocks support the insulating-glass unit, whether a gasket rolled behind the bead, which sealant batch was applied, or whether an opened drainage route was later covered. Once the unit is wrapped, those questions become expensive or impossible to answer without dismantling accepted work. The useful inspection follows one identified window through preparation, glass placement, retention and final review, preserving evidence before each layer conceals the last.
1. Freeze the complete glazing baseline by opening mark
Begin with the released opening mark, frame/sash identity and drawing revision. Reconcile every lite and cavity in the glass build-up, orientation and coating/interlayer positions where specified, heat treatment or safety route, processor/IGU identity, thickness designation, edge treatment, spacer and any permanent marking requirements. A shorthand such as ‘double Low-E safety glass’ is not a production baseline.
Add the retention system: approved glazing pocket and bead references; block types and functions; gasket profiles and joints; wet-glazing or bedding/sealant products; primers or cleaners where required; tapes, wedges or setting accessories; drainage/vent routes; and the exact system/manufacturer documents controlling them. Record substitutions and approval status rather than blending alternates into the BOM.
Define inspection stages and last-observable features. Incoming identity and edge condition exist before placement; pocket cleanliness and drainage before glass; block identity/location during setting; glass support and centring before beads; gasket condition during insertion; wet sealant preparation/application before cure; and final operation, visible workmanship and label traceability before packing.
| Layer/feature | Released source/revision | Physical identity | Last observable point | Required evidence |
|---|---|---|---|---|
| Glass/IGU build-up | Glass schedule and detail | Processor label/mark and unit ID | Before glazing/label removal | Identity and condition record |
| Pocket/drainage | System section/instruction | Frame/sash and route | Before glass/blocks cover it | Cleanliness and path evidence |
| Blocks/support | Approved glazing instruction | Product/batch and function | During placement | Identity, location and supported state |
| Beads/gaskets | System BOM/instruction | Profile and batch/lot | During installation | Orientation, joints and seated condition |
| Sealant/primer/tape | Approved product and application route | Product/batch/expiry where applicable | Preparation/application/cure stages | Compatibility, batch and process record |
2. Inspect pocket, glass and edge condition before setting
Confirm accepted material status and traceability. Inspect the relevant glass faces, edges and corners under safe handling conditions before they disappear into the pocket; preserve observed damage without assigning cause. Verify the lite/IGU identity to the scheduled opening and orientation. Do not infer coating surface, treatment or laminate construction from tint alone.
Inspect the pocket and contact surfaces against the exact system instruction: cleanliness, dry or conditioned state as required, debris and swarf removal, continuity of finishes, drainage/vent openings, required accessories and absence of unauthorised packing. Do not clean with an improvised solvent or scrape a coated surface merely to complete an inspection.
Record environmental and product-conditioning prerequisites only when the named manufacturer or approved process defines them. Sealants, tapes, primers and gaskets can have storage, substrate and application limits; a generic factory temperature or cure time must not be borrowed from another product.
| Gate | Observation/record | Source | Status if unresolved |
|---|---|---|---|
| Opening/glass identity | Mark, frame/sash, glass unit and orientation reconcile | Released schedule/detail | Hold glazing |
| Glass edge/face condition | Identified actual observation and photos | Approved inspection criterion | Quarantine/technical review |
| Pocket condition | Cleanliness, finish, surfaces and access | System instruction | Prepare under authorised method |
| Drainage/vent route | Open/intended path evidence | System drawing | Do not cover; hold |
| Materials | Blocks/gaskets/beads/sealant/primer/tape accepted | BOM and product records | Quarantine substitution/gap |
| Application conditions | Actual conditions where required | Exact manufacturer process data | Do not apply outside route |
3. Observe blocks, placement, beads and gaskets as a sequence
Link each block to its defined function and system position. Record product identity, opening mark, orientation/location and glass support state before retention hides it. Blocks should not be judged by colour or an inspector's generic spacing rule. Their material, dimensions, locations and interaction with glass edge, spacer, frame and drainage belong to the approved glazing design.
During glass placement, observe safe contact, centring and support using the specified method and tools. Record actual project-defined clearances only where a released criterion and suitable method exist. A visual gap is not a dimensional result, and forcing a glass unit into a pocket can damage edges, coatings, seals or frame finish.
For beads and gaskets, verify exact profiles, orientation, sequence, joints/corners, continuity, seating and damage against system instructions. Look for rolled, stretched, buckled, twisted, cut-short, contaminated or trapped conditions without converting those descriptions into a universal defect threshold. Confirm beads do not overwrite unit identity or block required drainage/vent paths.
| Stage | Physical identity | Observable characteristic | Evidence | Hold/decision |
|---|---|---|---|---|
| Block placement | Opening/glass/block lot | Function, position and contact state | Identified photo/record | Proceed / correct / hold |
| Glass placement | Glass unit and orientation | Support, contact and specified clearances | Actual observations/measurements | Proceed / technical review |
| Bead installation | Bead profile/position | Sequence, engagement and condition | Record | Accept / rework hold |
| Gasket installation | Gasket profile/lot | Orientation, continuity, joints and condition | Record | Accept / rework hold |
| Drainage recheck | Frame/sash route | Path remains unobstructed | Trace/photo where approved | Hold if blocked/unknown |
4. Control sealants and wet-applied materials by exact product and batch
Confirm manufacturer, product, colour/variant, batch and shelf-life status where applicable, storage/conditioning, substrate and adjacent materials. Link compatibility and adhesion evidence to the actual glass edge/seal, coating, spacer, gasket, frame finish, block and cleaner/primer combination. ASTM C1087 describes a method for determining compatibility of liquid-applied sealants with glazing accessories; a result covers its tested materials and conditions, not every product carrying the same generic chemistry name.
Record preparation and application against the approved manufacturer/process instruction: substrate condition, cleaning/primer route, mixing if applicable, application identity, joint fill/continuity and tooling, plus environmental and cure controls required for that product. This article supplies none of those values. Preserve deviations and interventions rather than wiping or over-tooling them out of the evidence record.
Protect the applied work during cure and later handling as specified. A skin or dry-looking surface does not prove full cure, adhesion or compatibility. If destructive or laboratory verification is required, use the authorised sampling, chain-of-custody and competent test route.
| Interface | Exact products/materials | Evidence scope | Application record | Open limitation |
|---|---|---|---|---|
| Sealant to glass/coating/edge seal | Manufacturer/product/batches | Compatibility/adhesion source | Opening/date/operator/conditions | Untested difference |
| Sealant to frame finish | Finish system and sealant | Approved evidence | Preparation/application | Batch/substrate variance |
| Sealant to gasket/block/tape | All contacting accessories | Test/manufacturer statement scope | Installed identities | Indirect or absent evidence |
| Cleaner/primer | Exact product and substrate | Manufacturer route | Actual use/batch | Unapproved substitution |
| Cure/protection | Exact sealant and assembly | Product/process instruction | Time/conditions/handling state | Not yet releasable |
5. Close the glazing record before packing removes access
Perform the project-defined final check in the correct support and operating state: opening/glass identity, visible glass and edge-zone condition, bead/gasket/sealant continuity, drainage openings, glass/frame contact concerns, hardware operation as separately specified, cleanliness and evidence completeness. Do not use aggressive cleaning or adjustment to make the inspection photo look better.
Reconcile upstream evidence to the finished opening mark: accepted glass/IGU, blocks, beads, gaskets, sealant and primers/cleaners; in-process records; compatibility evidence; NCRs and reinspection. Mark inaccessible or unobserved characteristics as such. A signed final photograph does not substitute for missing concealed-work records.
Release only the named unit/population and stage under the quality plan. Factory glazing approval does not establish glass design, structural capacity, safety compliance, seal durability, installed weather performance, warranty entitlement or shipment release. Preserve protected labels and traceability through packing.
FAQ
Can an inspector use a generic setting-block spacing rule?
No. Block type, function, location and dimensions must come from the exact approved glazing/system route. This guide supplies no configuration value.
Does a seated glazing bead prove the glass is supported correctly?
No. Support blocks, contact, clearances, pocket condition and internal preparation require their own in-process evidence.
Can glass coating orientation be checked by colour?
Not reliably. Use the approved identification or measurement method and processor/manufacturer records for the exact build-up.
Is a supplier statement that two materials are compatible enough?
Review the exact product and substrate identities, evidence method, tested conditions, scope and validity through the authorised technical route. Generic chemistry labels are insufficient.
Does sealant that feels dry mean the unit can be packed?
No. Follow the exact product's authorised cure and handling instructions; surface condition does not prove cure, adhesion or compatibility.
Should every glazed window be dismantled for inspection?
No universal destructive scope applies. Plan last-observable in-process evidence and any authorised sampling before concealment; do not dismantle accepted work without authority.
Does factory glazing inspection prove installed water performance?
No. Installation, perimeter interfaces, drainage, movement and field conditions are separate evidence routes.
Continue the project review
Connect this guide with the proposed window and door systems, then review how Cavorlen approaches manufacturing and quality control. When your schedule is ready, send it through the project review form.
Official sources used
National Glass Association — GANA Glazing Manual, IYOG Edition ↗ASTM International — ASTM C1087 compatibility of liquid-applied sealants with glazing accessories ↗ASTM International — ASTM C1193 guide for use of joint sealants ↗ISO — ISO 11600:2002 classification and requirements for building joint sealants ↗FGIA — Fenestration technical resources ↗Related buyer guides
This article is general factory-glazing inspection and evidence-control education. It is not glazing, structural, safety, sealant-joint, compatibility, drainage, edge-clearance, glass-selection, handling, lifting, repair or warranty design; a product specification; a test method; or a release certificate. It supplies no block type, location, spacing, hardness, length, bite, edge clearance, gasket compression, bead engagement, sealant chemistry, joint dimension, tooling, primer, cure, temperature, humidity, AQL, sample size, tolerance or acceptance value and does not state any Cavorlen glass, system, supplier, process, competence or performance. The released glazing drawings and schedules, exact glass/window/sealant manufacturer instructions, compatibility and adhesion evidence, governing standards and named qualified glazing, engineering and quality authorities must define and accept the actual assembly.