Compare the specified assembly, its support and movement details, its performance evidence and the installation sequence to define a complete curtainwall package.
What is a curtainwall system?
Curtainwall is a non-load-bearing exterior enclosure. Its framing and connections support the assembly and transfer applied loads to the building structure. It does not replace the structure carrying the building's floors and roof.
YKK AP's curtainwall guide describes systems that connect at floors or columns and may serve individual openings or span floors. The project still needs a defined load path, movement allowance, drainage strategy and interface with adjacent construction.
Stick-built and unitized describe different assembly approaches
Stick-built systems generally involve assembling framing and glazing at the site. Unitized systems use assemblies prepared and glazed in a shop before installation. Kawneer's system overview describes both approaches.
| Review item | Stick-built approach | Unitized approach |
|---|---|---|
| Assembly and glazing | Plan the specified field assembly, glazing and access sequence. | Confirm the shop assembly, glazing and site connection sequence. |
| Site logistics | Coordinate storage, work areas, field access and weather exposure. | Coordinate delivery order, unit storage, handling, lifting and access. |
| Interfaces | Resolve field joints, anchors and perimeter transitions. | Resolve unit joints, anchors, setting sequence and perimeter transitions. |
| Quality review | Identify factory and field checks required by the selected system and project. | Identify shop checks and the field checks needed at installed joints and interfaces. |
| Selection evidence | Compare the actual product documents and project constraints. | Compare the actual product documents and project constraints. |
Some systems combine field assembly with shop glazing. For example, YKK AP describes a stick-built system with shop-glazed cassettes. Read the selected manufacturer's assembly and installation documents before assigning work to the shop or field.
Compare access, design repetition, delivery, tolerances and the required installation sequence with the proposed system.
Coordinate support, movement and water management
Identify the supporting structure, connection locations and perimeter conditions on the project drawings. Reconcile the system's required movement allowances with building movement and construction tolerances. Keep transitions to adjacent walls, roofs and other enclosure work in the same review.
The manufacturer's curtainwall overview identifies load transfer, movement and water diversion as design considerations. The actual anchors, joints, drainage paths and installation sequence must come from the selected system and project documents.
Read performance criteria with the proposed configuration
- Structural: identify the required loads, support conditions, spans and movement criteria, then review the proposed system's supporting evidence.
- Air and water: record the specified test methods, conditions and acceptance criteria. Check the configuration covered by the reports and the project requirements for field testing.
- Energy: compare the required thermal and solar performance with the documented rating basis for the proposed framing and glass.
- Glass and infill: reconcile the specified makeup, treatment, coating, appearance, spandrel conditions and safety requirements with the system documents.
- Impact and approvals: verify the applicable project criteria and approval conditions for the proposed assembly instead of selecting from a generic product-family description.
NFRC's commercial certification program explains how certified fenestration ratings support an energy review. Keep the required rating documents with the selected framing and glass configuration.
Review the Florida approval path
Florida DBPR distinguishes state and local product approval, including state approvals with HVHZ scope for use in Miami-Dade. Confirm the applicable path, contract requirements and permit-review requirements for the project.
Check the document's current status, code edition and conditions of use. Compare the proposed size, glass, anchorage, substrate and required performance with the covered configuration. The state product search provides manufacturer, product, code-version and HVHZ search fields. Record any unresolved difference before release.
Compare curtainwall, storefront and window wall using the project
Start with the assembly named in the drawings and specifications. Compare its support, movement, drainage, opening layout and tested performance with any proposed alternative. A similar appearance does not establish that the systems have the same installation or performance requirements.
Use the storefront and commercial window comparison for the opening-level questions. A change to the specified assembly needs the project's review process and written scope resolution before fabrication.
What determines a curtainwall proposal?
A useful proposal needs the actual scope: elevations and sections, system and glass requirements, opening quantities, entrances and hardware interfaces, calculations and shop drawings, testing, finishes, delivery, access, lifting, installation sequence and work by other trades.
Compare written inclusions, exclusions and assumptions on the same project basis, using matching configurations, quantities and scope. Send the current drawings, specifications, schedules and addenda with the project address, bid date and installation period.
ACG reviews commercial curtainwall installation scope for Florida projects. Use the Division 08 specification guide and architect resource library to organize the questions, then send the bid package.
Frequently asked questions
Does curtainwall carry the building's floor loads?
Curtainwall is a non-load-bearing enclosure. Its assembly and connections support its own weight and transfer applied loads to the building structure. The main structure carries the building's floors and roof.
How do stick-built and unitized curtainwall differ?
Stick-built systems generally involve field assembly and glazing. Unitized systems use assemblies prepared and glazed in a shop before installation. The selected manufacturer's documents define the product's actual fabrication process and field interfaces.
What should be sent for a curtainwall bid?
Send current drawings, specifications, schedules and addenda with the project address, bid date and installation period. Include performance criteria, entrances, access, lifting, testing and work by other trades so the written scope can address them.
Which approval documents should be checked for a Florida project?
Confirm the project-required approval path, contract and permit-review requirements. Check the document's current status, code edition, applicable HVHZ scope and conditions of use against the proposed size, glass, anchorage and substrate.