Windows
The window is clear when nobody is doing anything
A window exists to be looked through. That single fact decides almost everything about specifying a switchable one, and it is why reverse mode is the usual answer here: the glass is clear with no power, draws nothing for the ninety per cent of the week nobody touches it, and turns private for the hour it is wanted.
Run it the other way round and the window is frosted every hour it is not switched, which undoes the reason there is a window.
Three windows, three different answers
Overlooked, and the view matters — PNLC
A bedroom onto a neighbour, a bathroom onto a street, a ground-floor room at the front. Clear with no power, private at a switch, and no blind in front of the glass the room was designed around.
Private most of the time — PDLC
A bathroom window that is frosted by default is not a compromise, it is the correct resting state. It is also the cheaper product, and a power cut leaves it private.
Sun rather than eyes — DLC
A west elevation is a glare problem before it is a privacy one. DLC moves between a tinted transparent state and a deep dark one, down to 1.5% light transmission, which is shading rather than concealment.
A switchable window does not go dark
The private state scatters light rather than blocking it. PDLC still transmits 83 to 90 per cent of the light falling on the glass: you cannot see through it and the room stays bright.
For a bathroom, a study or a street-facing living room that is exactly right. For a bedroom where somebody wants to sleep past sunrise, a hotel room, or any window where the requirement is blackout, it is the wrong product and a blind is the right one. DLC is the exception inside the range, and it is a different product at a different price.
The full argument is on film against blinds, including the case where the blind stays.
Whether the glass is already in the wall
| Film on the existing window | Laminated switchable glass | |
|---|---|---|
| When it applies | The window is in and staying | New work, or the glazing is being replaced anyway |
| What happens on site | Applied to the inside face, in hours | The unit is made and glazed in |
| Maximum panel | 72 × 165 in PDLC · 57 × 165 in PNLC and DLC | 70 × 165 in PDLC · 57 × 165 in PNLC and DLC |
| Cold range | -20 to 60 °C | -10 to 60 °C |
| Existing coatings | Tinted, reflective or low-E glass changes the result — confirm the make-up first | Specified with the unit |
| Insulated units | Not a retrofit. The switchable layer goes inside the unit when it is built | See the IGU page |
An exterior window is usually an insulating unit rather than a single pane, and a switchable layer goes inside that unit at the point it is made — it cannot be added to a sealed one later. What that changes for solar gain and HVAC load is on switchable glass in an IGU. The trade-offs between film and glass in general are on smart glass or smart film.
Common questions
Yes, to the inside face, where the glass is sound and accessible. Nothing is re-glazed. Existing tinted, reflective or low-emissivity coatings change the optical result, so the make-up is worth confirming before ordering rather than after.
No. The private state frosts rather than blocks — PDLC still transmits 83 to 90 per cent of the light. The room stays bright and nobody can see in. If blackout is the requirement, this is the wrong product.
Usually reverse. A window is clear for most of the week, so that is the state it should hold with no power, and the unit draws power only while it is private. Normal mode suits a window that is private most of the time, such as a bathroom.
The switchable layer goes inside the unit when the unit is made. It cannot be added to a sealed insulating unit afterwards — for an existing double-glazed window the options are film on the inside face, or replacing the unit.
PDLC does a little: the solar heat gain coefficient on laminated glass moves from 0.74 clear to 0.31 private, and infrared blocked from 20% to 80%. DLC is the product where solar gain is the actual requirement.
Built from the same six products
Office partitions
A wall of glass rather than one panel: where the joints fall, whether the run switches together, and how a door in the middle is matched to the panels beside it.
Read more
Doors
The one format where the glass moves, which makes the wiring the detail rather than the panel. Internal doors, entrances and glazed leaves in a partition run.
Read more
Shower enclosures
The room where the glass is the wall. Normal mode is frosted with no power, so a power cut leaves the enclosure private — which is the failure state a bathroom wants.
Read more
Room dividers
One room, or two. Fixed, sliding, stacking or folding — and the question that belongs to this format alone is whether power has to reach a panel that moves.
Read more
Skylights and overhead glazing
Overhead, the problem is usually the sun rather than the neighbours. DLC moves between a tinted transparent state and a deep dark one, which is glare and solar gain rather than privacy.
Read more
Railings and balustrades
Two projects in service — a New York waterfront terrace and a North Palm Beach pool deck. Reverse mode holds the view with no power drawn, and frosts for the hour it is wanted.
Read more
Specialized
Curves, display cases, cleanroom panels, studio sets and rear-projection surfaces. Rarely the shape that makes a project unusual — usually the edge, the movement or the duty cycle.
Read moreSend the opening, not the product code
Sizes, the shapes, whether the glass is already in the building and which state it should hold with no power. That is enough for a price and a lead time. Pompano Beach, Florida; (833) 333-8556.