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The market uses similar names for laminated glass, applied film and different electrically controlled technologies. The client should not begin by comparing three prices, but by confirming that every bid describes the same product type and scope.
A sound supplier can also say “this cannot be confirmed without the final configuration”. That is more professional than a universal value without a test method or a claim that one solution suits every wall, bathroom and facade.
1. Establish whether you are buying a pane, film or a complete system
Laminated PDLC glass is made to final size with the active layer inside the build-up. Applied film is installed on an existing surface. A complete system may also include frames, power supplies, controllers, cables, transport, installation and commissioning. These scopes are not directly comparable.
The quotation should name the product and its boundaries. If one company prices a pane and another owns a working partition, price difference alone does not show which proposal is better. Missing items must first be aligned.
2. Check technical data, sample and approval route
Ask for build-up, optical values with conditions, power, unpowered state, edge requirements, size and environmental limits. If a value depends on configuration, mark it for confirmation rather than replacing it with an arbitrary number.
A sample shows the clear and frosted character and angular behaviour. It does not automatically prove the result on a large pane in different light. The manufacturer should explain how the sample relates to the final product and when a mock-up is required.
| Document | What it should contain | Why it matters |
|---|---|---|
| Configuration sheet | Build-up, state, power, limits | Product comparability |
| Pane drawing | Size, processing, orientation, cable | Safe manufacture |
| Scope matrix | Who supplies and installs each item | No delivery gaps |
| Handover record | State, controls and view tests | Shared result criterion |
3. Assess competence at the glass, structure and electrical interfaces
An active pane needs an appropriate frame, protected edge and controlled connection. A manufacturer should ask about support, tolerances, installation direction, door movement, clashes and service access. Missing questions do not simplify the project; they move risk to site.
The electrical scope must define power supplies, channels, routes, switches, controllers, scenes and final connection responsibility. Integrated controls should also provide simple local operation and documented failure behaviour.
4. Compare scope, programme and change rules
Programme should start from a defined gate: approved drawing, payment, supplied data or manufacturing readiness. Consequences of changing size, frame, zones or controls after approval should also be described.
Transport, handling, protection, access equipment, out-of-hours work and site preparation can materially affect cost. A clear proposal does not hide these conditions in small print. It shows what is included, client-supplied and pending confirmation.
5. Handover and service reveal whether the solution is built for years
Handover should check both glass states, local and central controls, channel labels, power-loss behaviour, detailing and views from agreed positions. Documentation also identifies equipment and safe isolation.
Ask how faults are reported, what information is needed, who diagnoses power and controls, and whether equipment remains accessible. Service does not begin with a phone number after failure. It begins with a design where the power supply can be reached without dismantling the wall.
In practice: Use the DGF checklist to compare proposals and ask every supplier to mark each item as included, client scope, another contractor or to be confirmed. Compare cost only after that.