LINEO
Concealed linear slot diffuser — ventilation as a single clean line across the ceiling.
- Supply & extract
- Paintable
- Flush ceiling mount
- Plasterboard-ready
Best for: A linear, minimal ceiling detail in living spaces and suites.
Guide
Frameless air vents for uninterrupted ceilings and walls
A frameless air vent has no visible border around its opening. Where a conventional vent cover relies on a frame to hide the cut edge of the ceiling, a frameless diffuser is plastered directly into the surface so the finish runs right up to the air gap.
Removing the frame is what lets ventilation blend into a designed surface. This guide covers what “frameless” really means and how to specify it.
Why the frame is the problem
A frame does two jobs on a normal grille: it covers the rough edge of the opening, and it holds the grille in place. It is also the single most visible part of the vent — a rectangle of plastic or metal sitting proud of the ceiling. On a plain painted plane, the eye goes straight to it.
A frameless diffuser handles the edge differently: the opening is finished by plaster and paint, so there is nothing to sit proud and nothing to see except the functional gap.
How a frameless finish is achieved
The diffuser includes a flange that the plasterer skims over, bringing the ceiling surface flush to the edge of the slot or opening. Once painted, the transition from ceiling to air gap is a clean line with no border. Achieving this well depends on careful coordination with the plastering trade.
This is why frameless vents are a construction detail, not just a product choice: the quality of the result depends on the installation as much as the diffuser itself.
Frameless slots vs frameless points
Frameless linear slots (the LINEO family) read as a thin architectural line and suit continuous, deliberate ceiling detailing. Frameless round and square points (RONDO / KVADRO) suit individual rooms where a single discreet outlet is enough. Both remove the frame; they differ in the shape of what remains.
The right choice depends on the room, the airflow required and the design intent — covered in our guide to choosing a diffuser.
When to use it
When this is the right solution
Plain painted ceilings
Where any frame would break an otherwise continuous surface.
Minimal interiors
Design languages that avoid visible hardware entirely.
Linear detailing
Ceilings organised around lines of light, shadow gaps and joinery.
Feature surfaces
Walls and ceilings treated as a single clean plane.
Before you order
What to confirm first
Concealed diffusers are specified against the project, not from a shelf. Confirm these before ordering:
- That the ceiling or wall is plasterboard/gypsum suitable for a flush, plastered finish.
- Duct size, airflow and direction for each position.
- The plastering and painting sequence, and who is responsible for the flush finish.
- Maintenance access requirements for each position.
- The model and configuration against current manufacturer documentation.
All technical data must be verified against the current manufacturer documentation for your specific configuration before specification and installation.
Products
Relevant ERGOVENT products
RONDO
Round concealed point diffuser — a discreet circle of air, flush with the surface and painted to match.
- Supply & extract
- Paintable
- Flush ceiling or wall mount
- Plasterboard-ready
Best for: Round ceiling or wall integration — renovations and room-by-room ventilation.
Frequently asked questions
- What is the difference between a frameless vent and a normal grille?
- A normal grille has a visible frame that sits on the surface; a frameless vent is plastered into the surface with no border, so only the air opening remains visible.
- Is a frameless air vent harder to install?
- It requires coordination with the plastering and painting trades to achieve the flush finish, so it is more involved than screwing on a grille. Our team supports the contractor with guidance.
- Can frameless vents be used on walls?
- Some models suit wall installation as well as ceilings. Confirm the intended surface with us so the correct configuration is specified.
- Do frameless vents come in different shapes?
- Yes — round and square points (RONDO / KVADRO) and linear slots (LINEO family). The shape you choose depends on the room and the airflow required.
- Are frameless air vents suitable for Thai villas and condos?
- Yes. They are a common choice for premium interiors in Thailand, and ERGOVENT Thailand supplies them with local selection support.
Specifying concealed diffusers for a project?
Send your ceiling plans and duct sizes and our Thailand team will recommend the right models, confirm the configuration and prepare a quotation.