Building Types

Curtain wall high-rise

Unitized glass-and-aluminum envelopes are the most common high-rise construction type in Metro Vancouver, and the most unforgiving of a badly matched access plan or cleaning method.

What Makes It Different

A continuous system, not a wall with windows in it

Curtain wall assembles glass, spandrel panels, and aluminum mullions into a single skin that's hung off the slab edge and sealed at every joint. There's no masonry or stucco behind it doing structural or weatherproofing work — the glazing system itself is the entire building envelope. That has two practical consequences for maintenance: first, the whole elevation reads as one continuous surface, so uneven cleaning or missed panels are visually obvious in a way they aren't on a punched-window facade. Second, every joint, gasket, and sealant run is a potential water path, so condition issues found during cleaning — cracked sealant, failed gaskets, fogged insulated glazing units (IGUs) — are worth documenting even though fixing them isn't part of a cleaning scope.

Vancouver's stock of Class A towers built from the late 1990s onward is almost entirely curtain wall or a close variant (unitized panel systems, structurally glazed systems). That makes this the default building type most property and asset managers downtown are dealing with, even if they haven't thought of their building in these terms.

Failure Modes

What actually goes wrong on curtain wall

  • Sealant degradation
    UV and thermal cycling break down wet-glazed sealant joints over 15–25 years, leading to water infiltration at the mullion-to-glass interface.
  • IGU seal failure
    Insulated glazing units lose their edge seal and fog between the panes — a glass replacement issue, not a cleaning one, but often first spotted during a cleaning visit.
  • Spandrel panel staining
    Opaque spandrel glass behind mechanical floors traps heat and can show discoloration or off-gassing residue distinct from vision glass soiling.
  • Mineral etching on vision glass
    Hard water from irrigation overspray or inadequate rinsing during cleaning can permanently etch coated glass — see Stage 1–4 glass damage in our glossary.
  • Gasket shrinkage
    Rubber glazing gaskets shrink and pull back from the frame over time, creating a visible gap and a minor water path even where sealant is intact.
Access Strategy

How curtain wall towers get accessed

Access is set by roof condition, not preference. A tower with a certified roof davit (RDS) or track-mounted swing stage system will default to suspended platform work for full-elevation cleaning, since it covers the most glass per hour once rigged. Towers without a permanent system, or with setbacks and mansards that make a swing stage impractical, move to rope access, which handles irregular geometry more efficiently. Ground-accessible elevations — podiums, loading areas — are typically finished with a boom lift or ground crew rather than dropping a full rig for a few storeys of glass.

See our full comparison of access methods for setup time, cost drivers, and WorkSafeBC requirements for each.

Frequency

Recommended cleaning frequency

Elevation / featurePlanning-range frequencyWhy
Lobby-facing / plaza elevationQuarterlyLeasing and visitor visibility sets the standard, not soiling rate alone.
Waterfront or high-exposure elevationQuarterly to bi-monthlySalt-laden air and wind-driven rain accelerate mineral deposit.
Service / lane-facing elevationSemi-annualLow visibility, exposure still present but tolerance is higher.
Full anchor/rigging inspectionAnnualPer WorkSafeBC and CSA Z259 guidance for permanent fall-protection systems.
Scheduling

Sequencing and scheduling constraints

Wind holds are more frequent above the 20th storey — build float into any hard deadline
Rope access and swing stage work is typically restricted below ~15 km/h gusts at height
Elevation sequencing should start on the leeward side and move with the weather window
Swing stage rigging and de-rigging can take longer than the clean itself on a first visit
Winter freezing limits water-fed pole and rinse-based methods below roughly 4°C
Tenant Impact

Managing tenant and resident impact

Most curtain wall cleaning happens from outside the glass line during business hours, so tenants see the crew work past their windows but aren't displaced. The main coordination point is boardrooms and executive floors, where a scheduled pass can interrupt a meeting or video call — property managers typically circulate a floor-by-floor schedule 48–72 hours ahead so tenants can flag conflicts. Swing stage rigging on the roof and tie-back points sometimes requires brief access to mechanical penthouse or roof-level tenant space, which should be arranged separately.

Compliance

What to check before work starts

Current WorkSafeBC clearance letter and certificate of insurance from the contractor
Anchor/davit inspection record less than 12 months old
Fall-protection plan specific to the building, not a generic template
IRATA/SPRAT certification records for rope access technicians
Strata bylaw or building rules sign-off if roof or common-area access is required
Scope of Work

What to put in the scope

A curtain wall scope of work should specify: which elevations and which glass (vision, spandrel, mansard) are included; the access method for each; frequency per elevation rather than a single building-wide number; cleaning method and any restrictions (no razor blades on coated or tempered glass, purified water only, pH range for detergents); condition reporting requirements (photograph and log any sealant, gasket, or IGU issue found); and anchor/rigging responsibilities, including who confirms davit certification is current before the crew uses it.

FAQ

Common questions

How is curtain wall different from a punched-window facade for maintenance purposes?+

Curtain wall is a continuous, unitized glass-and-frame system hung off the slab edge, so the whole envelope — glass, mullion, and sealant joint — acts as one weather barrier. Punched windows sit in a load-bearing wall, so failures are more localized and the wall itself sheds water independently of the window.

Does window cleaning frequency affect sealant life on curtain wall?+

Routine cleaning itself has negligible effect on structural or wet-glazed sealant. What matters is using neutral-pH cleaning agents and avoiding solvents that aren't sealant-compatible, and flagging any sealant that looks cracked, chalky, or pulled away from the glass during the visit so it gets into the building's maintenance record before it becomes a leak.

Who is responsible for anchor and davit inspection on a curtain wall tower?+

Ownership or strata is responsible for maintaining the roof anchor or davit system per the engineer of record's design and WorkSafeBC requirements, typically via annual inspection by a qualified person. Contractors performing rope access or swing stage work verify condition before each use but don't own the inspection program.

Get a scope built for your curtain wall tower

Send building height, glazing type, and any known anchor restrictions and we'll return an access plan with the estimate.

Next step

Get a budget number today, or book twenty minutes on site.