Curtain Wall Shop Drawings Explained: A Complete Review Guide

What are curtain wall shop drawings?

Curtain wall shop drawings are the engineered, fabrication-ready documents a facade specialist produces to build your curtain wall exactly as it will be manufactured and installed. They take your design intent - module, elevations, glass make-up and performance targets - and add every dimension, section, anchor, gasket, thermal break and drainage path needed to actually cut aluminium, assemble units and hang them on the structure.

The distinction between design intent and shop drawings is where projects most often go wrong, so it is worth stating plainly. Design intent belongs to the architect; shop drawings belong to the specialist contractor; and your job is to verify that the translation between them is faithful and code-compliant, then approve it.

• Design intent (architect): module and grid, elevations, glass type, U-value/SHGC/VLT targets, finish and key sections
• Shop drawings (specialist): mullion and transom profiles, wall thicknesses, anchor and bracket design, gaskets, thermal breaks, drainage and every junction
• Your role: confirm the translation honours your intent and the codes, then stamp it

The liability line matters too. When you stamp shop drawings you are confirming they honour your design intent and the applicable standards - you are not taking over the structural design of the anchors, which remains the specialist's engineered responsibility. Keep that boundary explicit in both the contract and your review comments so accountability is never ambiguous.

Stick vs unitised: which system the drawings describe

Before you review anything, know which system you are looking at, because the drawings and the risks differ sharply. Stick and unitised curtain walls solve the same problem in opposite ways, and the choice shapes cost, programme, quality and site logistics.

A stick system is assembled piece by piece on site - mullions, transoms, then glass - so it suits low-to-mid-rise buildings and tighter budgets, but it puts more sealing and quality control in the hands of site labour. A unitised system arrives as factory-glazed, pre-tested units that interlock at split mullions and stack joints, giving faster, more weather-reliable installation on taller towers at a higher unit rate.

• Stick: lower material cost, slower install, more site-dependent quality, best for smaller facades
• Unitised: factory quality, fast crane-set install, superior water-tightness, best for towers and tight programmes
• Semi-unitised: a hybrid where ladder frames go up first and infill panels follow

For a unitised set, expect the split-mullion and stack-joint details that let one unit interlock with the next and absorb building movement. For a stick set, expect a clear on-site assembly sequence and the toggle or captured-glass retention detail. Where a facade transitions into a fully bolted glass wall at an atrium or feature bay, confirm the same logic carries through the structural glazing details - silicone bite, setting blocks and weep path all dimensioned, not assumed.

What a complete shop drawing set contains

A reviewable set is far more than elevations - it is a coordinated package that lets you trace any point on the facade from overall layout down to a sealed joint. If a submittal arrives with only elevations and one typical section, send it back, because you cannot review interfaces you cannot see.

• Key plans and elevations with grid references and panel/module numbering
• Typical vertical and horizontal sections through mullions and transoms at full scale (1:1 or 1:2)
• Anchor and bracket details showing the slab-edge relationship and three-axis adjustability
• Every interface detail: base, parapet, corner, window/door, spandrel, soffit and movement joint
• Glass make-up schedule: coating, cavity, low-E surface number, IGU spacer and edge seal
• Gasket, thermal break and drainage/pressure-equalisation diagrams
• Fabrication tolerances, test pressures and applicable standards referenced directly on the sheet

The operable elements and ironmongery belong here as well - vents, restrictors, locks, and the door hardware for any entrance leaves within the facade should be scheduled on the drawings rather than left to site improvisation. You can see how these packages come together across a range of completed elevations in our recent projects, which is a useful reference when judging whether a submittal is genuinely complete.

Performance criteria to verify on the drawings

Check the drawn system against the numbers you specified, not against a product name. For Hyderabad's hot, glare-heavy climate, solar control usually drives the glazing decision more than U-value alone, and the figures below are the ones that actually protect the building and its energy bill.

• Wind load: design pressure derived from IS 875 Part 3 for the building's basic wind speed (Hyderabad sits in the 44 m/s zone), height and terrain category
• Deflection: framing typically limited to L/175 for spans up to about 4.1 m, or 20 mm, whichever is less - confirm the figure on the drawing
• Thermal: U-value and SHGC of the assembly, aligned to ECBC and your IGBC/GRIHA/LEED credit path
• Daylight and glare: VLT balanced against SHGC - a low SHGC (around 0.25-0.30) with adequate VLT (around 40-50%) is the Hyderabad sweet spot
• Acoustics: weighted sound reduction index Rw, typically 35-40 dB near arterial roads or the Outer Ring Road
• Air, water and structural performance: air infiltration, static and dynamic water penetration, and structural test pressures per ASTM or equivalent methods
• Fire: perimeter fire-stopping at every slab edge and any spandrel requirements per NBC 2016

Every one of these belongs on the sheet as a stated value, not in a covering email. A drawing that references the glass by trade name but omits the low-E surface number, the SHGC and the deflection limit is not reviewable, and approving it transfers the ambiguity - and the risk - straight onto your stamp.

Tolerances, interfaces and building movement

Most facade failures trace back to tolerances and interfaces, not to the panels themselves. The curtain wall is fabricated to tight tolerances but hangs off a concrete frame built to far looser ones, so the anchor must absorb the difference - and if it cannot, something cracks, leaks or goes visibly out of plumb.

• Confirm anchor adjustability in three axes accommodates realistic frame tolerances of 15-25 mm (in/out, up/down, left/right)
• Typical facade tolerances: plus or minus 3 mm alignment across a bay, plus or minus 1.5 mm joint width - verify these are stated and achievable
• Check thermal movement: aluminium expands roughly 0.024 mm per metre per degree Celsius, so a 3 m member across a 40 degree swing moves a few millimetres that joints must absorb
• Inter-storey drift and live-load slab deflection must be accommodated at stack joints and slab edges
• Every interface with another trade (RCC, masonry, roofing, internal finishes) needs a detail and a clear responsibility line for the seal

Interfaces are also where the curtain wall meets the rest of the envelope - a punched window, a terrace door, a parapet coping or a ground-floor entrance. Each of those junctions must be drawn, drained and sealed with a single named responsible party, because an undrawn interface is a future callback with your stamp on it. When in doubt, insist the drawing shows the water's escape route explicitly: pressure-equalised chamber, weep hole, and where the water finally exits the wall.

Hardware, sealants and finishes to confirm early

Shop drawings are also where ironmongery, sealants and finishes get pinned down, and this is easy to defer until it becomes a site problem. Locking these in at drawing stage protects the programme, because anodised and PVDF batches carry real lead times and colour-matching later is expensive.

• Vents and operable lights: hinges, restrictors and locking, scheduled with their glass thickness and weight
• Doors within the facade: handles, locks and closers matched to the leaf weight and traffic
• Feature glazing: patch and spider fittings sized for the glass and the wind load
• Finish: anodising (grade and micron) or PVDF/powder coat with film thickness and a colour reference (RAL or bespoke)
• Sealants: structural and weather silicone with compatibility and adhesion test requirements stated

Require the fabricator to note the exact model and finish of each component on the schedule so procurement and drawing always agree. A mismatch between the drawing and the delivered handle, closer or spider fitting is a small item that can stall an entire floor's handover. If you want the full component and finish scope mapped before you commit, browse our services or ask the team to build the schedule with you at design-assist stage.

How to specify so the drawings go smoothly

The cleaner your specification, the faster and more faithful the shop drawings. Specify by measurable criteria, reference standards by name, and require submittals that let you verify rather than assume - a vague specification produces a slow, argumentative review cycle and a resentful fabricator.

• State performance as numbers: U-value, SHGC, VLT, Rw, wind pressure, deflection limit and test pressures
• Name the standards: IS 875 Part 3 (wind), IS 2553 (safety glass), NBC 2016, ECBC, and the ASTM test methods you expect
• Require a mock-up or performance test regime for significant facades before mass fabrication
• Ask for anchor calculations and structural design by a qualified facade engineer, submitted with the drawings
• Define finish clearly: anodising or PVDF/powder coat, film thickness and colour reference
• Set a review turnaround (typically 10-14 working days) and a clear approval/resubmission protocol so the programme holds

Include a submittal register in the specification that lists exactly what you expect and when - samples, calculations, test reports and the drawing sequence itself. This is also where engaging a specialist early pays off: design-assist lets buildability and cost feedback shape the facade before it is frozen, so problems surface at concept rather than at approval. If you want that conversation started before you commit the design, get a free quote and bring the detailing capability to the table early.

A practical shop drawing review checklist

When a set lands on your desk, work it in a fixed order so nothing slips through. A disciplined pass through the same checklist every time is faster and more reliable than reading the drawings front to back and hoping you catch the gaps.

• Does the glass make-up on the schedule match your specified U-value, SHGC and VLT exactly, low-E surface included?
• Is the wind pressure stated, and is the deflection limit shown and met for the worst-case span?
• Are anchor adjustability and the slab-edge relationship drawn, with the three-axis range dimensioned?
• Is every interface - base, head, jamb, corner, parapet, spandrel, movement joint - detailed and drained?
• Are gaskets continuous and pressure-equalisation/weep paths shown, not merely implied?
• Are tolerances, test pressures and standards printed on the sheets themselves?
• Do the finish, sealant and hardware schedules match the specification and the procured products?
• Are fire-stopping and perimeter details per NBC 2016 shown at every floor?

Mark the set up, return it with unambiguous comments, and require the resubmission to show your comments resolved point by point. For a typical mid-rise facade in Hyderabad or Secunderabad, budget one or two review cycles; a project where the specification was tight and design-assist happened early often clears in a single cycle.

Costs, timelines and local context in Hyderabad and AP

Curtain wall economics and the shop-drawing programme go together, and knowing the local numbers helps you review sensibly. Realistic installed rates in the Hyderabad and Secunderabad market give you a sanity check on whether the drawn system actually matches the budget you approved.

• Unitised curtain wall: roughly INR 6,500-11,000 per sq m installed, depending on glass and finish
• Stick-system curtain wall: roughly INR 4,500-8,000 per sq m installed
• High-performance low-E double glazing typically adds INR 800-1,800 per sq m over single glazing
• A visual and performance mock-up for a significant tower: commonly INR 4-9 lakh, and worth it
• Shop-drawing production for a mid-rise facade: usually 4-8 weeks from award, before review cycles begin

Local climate should shape what you approve. Hyderabad's long hot season rewards a low SHGC to cut cooling load, while the monsoon rewards obsessive attention to drainage and pressure equalisation - both are decided on the shop drawings, not on site. If you are commissioning a facade anywhere in Telangana or Andhra Pradesh and want the detailing done right the first time, our team can take a curtain wall glazing project from design-assist through fabrication and installation, so the drawing you stamp is the wall that gets built.