Define the surface before comparing proposals
The terms double-curved, compound-curved and multi-curved can be used differently across project teams. Identify the actual surface to be supplied. Clarify whether the design calls for a genuinely curved surface, a series of separate cylindrical curves or a faceted arrangement of flat panels.
A rendered image communicates the appearance, while a dimensioned model or drawing defines the geometry. Send both where available and explain which information controls the quotation.
- Overall surface, panel boundaries and panel marks
- Intended smooth or faceted appearance
- Project application and country
- Design stage and geometry items still open
Prepare a model and drawings that describe the same revision
Share the available 3D model, dimensioned sections and a panel schedule. Confirm a file format the supplier can review. Identify the coordinate system, units, model revision and the glass surface represented by the geometry.
A radius in one section alone may not describe a surface that changes in another direction. Useful review information can include sections in both principal directions and the intended edge geometry. Where the construction has multiple panes, identify which surface is the geometric reference.
- 3D model with units and a named revision
- Panel boundaries, section locations and edge geometry
- Pane reference surface and face orientation
- Repeated, unique and mirrored panels separated in the schedule
Keep construction, supports and performance requirements together
State the proposed pane build-up, heat treatment, interlayer, coatings and appearance requirements. Include the intended support arrangement and available framing drawings so the supplier understands the interface being discussed.
Loads, deflection limits, safety requirements and project acceptance criteria must come from the responsible design team. An available manufacturing route or a visually similar reference does not establish the structural suitability of a proposed panel.
- Proposed glass layers, interlayers and cavities
- Coating positions, tint and visible appearance requirements
- Support and frame interface information supplied by the design team
- Required performance evidence and the exact construction to which it must apply
Agree what a feasibility review or sample is intended to establish
Ask what can be assessed from the initial information and which questions require further drawings, samples or project-specific review. If a sample or mock-up is proposed, agree its geometry, construction and the feature being checked.
A finish sample can help compare appearance. A geometry sample can support a forming discussion. Neither automatically verifies the complete installed assembly. Record who approves each stage and whether the quotation includes the proposed review, tooling, sample or mock-up scope.
- Purpose and acceptance criteria of any sample or mock-up
- Quoted allowances for review, tooling or development, where applicable
- Drawing approval and change-control responsibilities
- Items excluded from the initial proposal
Make the commercial comparison traceable
Ask each supplier to identify the model revision, panel quantities and build-up used for its proposal. Separate confirmed supply items from provisional allowances. If a proposal assumes a different geometry or construction, ask for that difference to be stated explicitly.
Packing, delivery destination, inspection documents and the basis of any programme should also be written into the proposal. A meaningful price comparison starts with the same scope and records the remaining differences.
Start with the files you have and a list of open decisions
Send the available geometry and explain the intended application. State which requirements are fixed and which are still being developed. We can use that information to discuss the supply enquiry and the next information needed for a project-specific quotation.
Send files separately by email. If you first use the form, include its EMG reference when emailing the drawings so the material can be matched to the enquiry.
Project / application / country: Model format, units and revision: Panel schedule and approximate quantities: Glass reference surface: Proposed build-up and finish: Support / framing information available: Required project documents: Sample or mock-up questions: Destination and timing: Open design decisions:
Project questions
Can a rendering establish the double-curved geometry?
A rendering helps communicate appearance. A supplier still needs geometry and panel information to assess what is being requested. Send the model and drawings where available, and mark provisional geometry clearly.
Can I use a previous project as proof of performance for a new build-up?
A previous project can illustrate supply experience. Performance evidence must be checked against its stated construction, dimensions, support conditions and scope before it is used for another project.
YOUR PROJECT, YOUR DRAWINGS
Discuss your double-curved glass project
Include your application, glass build-up, approximate quantities and delivery destination. Email drawings separately and identify the revision.