Glazing Takeoff:
Curtain Wall vs Storefront

Separate the systems

The first step in any glazing takeoff is classifying what you're actually looking at. Curtain wall is a continuous, structurally independent facade system that spans multiple floors and carries its own dead load back to the building structure — it doesn't bear on the slab edge at each floor. Storefront, by contrast, is a non-load-bearing system installed within punched openings, typically at the ground floor, bearing on a sill and secured to a head jamb above.

On a commercial set these two systems often appear on the same elevation sheet, and the glazing schedule may list them in a single table. Before you count a single square foot, sort every opening by spec section: storefront typically falls under CSI 08 41 13 and curtain wall under 08 44 13. The framing profiles, anchor details, and unit costs are completely different, so mixing them in a single line item guarantees an error.

Take off each system by elevation square footage — not plan length and not opening count. Glazing quantities are vertical, and plan views compress them. Pull elevation drawings for every facade, measure each distinct system, and confirm the totals against the glazing schedule. Group quantities by elevation tag so your review is traceable.

• Curtain wall: continuous, spans floors, carries its own structural load
• Storefront: non-load-bearing, ground-floor punched openings, sill-bearing
• Quantity unit: elevation square footage, not plan length
• Group by system type per the glazing schedule and spec section

Cost-per-square-foot benchmarks

Storefront systems run roughly $25 to $60 per square foot installed for standard commercial aluminum framing with insulated glass — that's the range you'd see on a retail shell, office lobby, or school entry in 2025 (Insight Glass / HomeAdvisor benchmarks). The wide spread reflects frame depth, glass specification, and site complexity. Narrow-profile thermally broken frames with high-performance glazing sit at the top; standard non-thermally-broken tube framing with clear IG sits at the bottom.

Curtain wall pricing is a different conversation entirely. Low-rise stick-built systems on a two- or three-story structure run $25 to $75 per square foot — comparable to mid-range storefront in material cost but with higher labor due to the structural attachment and perimeter sealant requirements. Tall multi-story systems, where unitized panels are fabricated off-site and craned into place, routinely run $200 to $400 per square foot, driven by engineering, fabrication tolerances, and crane time (Insight Glass, 2025).

Punched commercial windows — aluminum-framed units set into masonry or stud openings — fall in a separate bracket at roughly $50 to $150 installed, depending on frame type and glass make-up.

Crew productivity

Labor is often the swing item on a glazing bid, and storefront productivity benchmarks are reasonably well-established. A two-person glazing crew installs roughly 150 to 250 square feet of storefront per day under normal conditions — the range accounts for floor-to-ceiling height, number of corners and transitions, door frames requiring closer hardware, and site access (United Facade, 2025). A 2,000 square foot package — which is a common size for a ground-floor commercial entry and retail frontage — takes two to three weeks from first frame to punch list completion.

Curtain wall erection is slower on a per-square-foot basis and frequently crane-dependent. Unitized systems move faster once the crane is rigged, because full-story panels clip into the building structure in sequence, but setup, surveying, and panel certification add overhead that storefront doesn't carry. On a stick-built curtain wall, each mullion is set, shimmed, and sealed individually, which makes productivity highly sensitive to the complexity of the framing grid.

When building your labor estimate, confirm which trades are in scope. Glazing subs typically own the framing and glass, but caulking and sealant at the perimeter may fall to a separate waterproofing sub, and anchor installation at the structure may be the GC's work. Scope gaps here can erase margin quickly.

Glass share of cost

Glass is typically 40 to 60 percent of total material cost on a glazing package (United Facade, 2025). That means your glass line item is your biggest material exposure, and it's the one most likely to blow up if the spec changes late. Before you price the glass, read the spec section carefully — the make-up sentence (e.g., "1-inch IGU, low-E on surface 2, clear inner lite, argon-filled") drives the unit cost more than glass area does.

Insulated glass units (IGUs) with standard low-E coatings are the baseline for most commercial work. Laminated glass, required in overhead glazing and some hazard locations, adds meaningful cost per square foot. Spandrel glass — the opaque panels that conceal slab edges in curtain wall — is priced differently from vision glass and is easy to omit when counting elevation area. High-performance coatings, fritted glass, and electrochromic glazing all carry premium pricing that needs to be confirmed with the glazing supplier before the bid goes out.

• Glass is 40–60% of total material cost — confirm make-up before pricing
• Insulated, low-E, laminated, and spandrel glass all carry different unit costs
• Spandrel panels at slab edges are easy to miss — count them separately
• Confirm glass specification in the spec section before locking in supplier quotes

Capture the full scope

Glass and framing are the headline quantities, but a glazing takeoff that stops there will consistently undercount the package. Aluminum framing extrusions should be taken off by linear foot of mullion — vertical and horizontal — rather than as a lump derived from area. This matters because corner conditions, intermediate transoms, and custom profiles are priced by the foot from the fabricator, and area-based estimates miss the detail.

Doors and entrances within the glazing system are almost always a separate line item. Count each door unit, note hardware groups (closer, panic, hold-open arm), and flag any power-operated doors that need an electrical allowance. Hardware for commercial entrances is not trivial — a heavy-duty pair with closers and panic devices can add $1,500 to $3,000 over the frame cost alone.

Below the framing, every glazing package requires gaskets, wet sealant at the perimeter, backer rod, and flashing at the sill. These consumables are small in cost but confirm scope ownership with the GC before the bid. Finally, note the thermal performance requirements in the energy section of the spec — U-factor and solar heat gain coefficient (SHGC) requirements directly determine which glass make-up qualifies, and a project in IECC Climate Zone 5 or above will restrict your options compared to a Sun Belt project.

• Aluminum extrusions: take off by linear foot of mullion, not area
• Doors and hardware are a separate line — include closer, panic, and power-operator allowances
• Confirm scope ownership for gaskets, sealant, backer rod, and flashing
• Note U-factor and SHGC requirements — they constrain your glass selection

Questions estimators actually ask