Continuous linear slot diffusers
Design uninterrupted linear runs with active and inactive sections. SelectiV helps configure the layout and automatically determines the individual components required.
SelectiV · Air distribution design software
Don’t just design air distribution.See it perform.
The next generation of HVAC air distribution design is here. And it’s free.
What if you could see how air moves through a room before it’s built? Compare heating and cooling performance, explore different diffuser configurations, and let intelligent Auto-Design find the optimal solution?
SelectiV combines proven diffuser performance data with advanced airflow physics to take room air distribution design beyond catalogue tables and traditional selection methods.
Stop guessing. Start engineering the room.
2027 AHR Expo Innovation Awards · Software category finalist
selectiv.design Side view
Room First. By design.
The room changes everything.
For decades, engineers have selected diffusers based primarily on catalogue performance data: throw, pressure drop, airflow and noise.
But a diffuser doesn’t operate in a catalogue. It operates in a room.
SelectiV brings the room into the design process. Instead of evaluating diffusers in isolation, engineers visualize how air distribution performs within the actual space, for more informed decisions about occupant comfort, airflow patterns and system performance.
The objective isn’t simply to select a diffuser.
It’s to engineer the right conditions for the people inside the room.
What SelectiV accounts for in its airflow computations
- 01 Ceiling height
- 02 Room geometry
- 03 Heating and cooling temperatures
- 04 Airflow rates
- 05 Adjacent walls
- 06 Competing air jets
Visualize airflow
See the invisible. Before you build.
Air is invisible. Its impact shouldn’t be. Create your room in an intuitive 3D environment, position your diffusers, define operating conditions and visualize predicted airflow throughout the space.
20150 fpm
Cooling · 55 °F Heating · 90 °F 3D preview: an approximate reconstruction from the top, front and side views.
1 Ceiling attachment Supply air clings to the ceiling and spreads.
2 Jets meet Where neighbouring jets collide, air drops between them.
3 Windows The LSD slots wash the glazing with a curtain of air.
4 Floor jet The jet runs down the wall, reaches the floor and spreads across it.
5 Occupied zone Below 6 ft: where comfort is judged.
Occupant-zone performance: evaluate predicted air velocities where comfort matters most. Don’t just select air terminals. Understand how they work together.
Auto-Design
What if your best design isn’t the first one you think of?
Traditional air distribution design relies heavily on experience, judgment and time-consuming manual comparisons. Let Auto-Design explore the possibilities for you.
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01
Describe the room and the goal
Total airflow, ceiling type, mounting, diffuser shape, air curtains at the windows: Auto-Design suggests families of layouts suited to the room.
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02
Compare thousands of solutions
By analyzing thousands to hundreds of thousands of combinations, Auto-Design evaluates diffuser sizes, configurations, quantities and locations, and ranks the results with throw, NC and perceived NC.
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03
Apply it in the room
The chosen solution is placed in the 3D room, ready to visualize, refine and document. Less trial and error. More intelligent design.
Not CFD. Built for everyday design.
The power of physics. The speed of selection.
Catalogue tables provide useful product data. CFD delivers detailed numerical airflow analysis. But most everyday design decisions need something in between.
Catalogue tables
Useful product data, evaluated outside the room.
- Fast
- Isolated
SelectiV
Manufacturer performance data, established air distribution principles and physics-informed calculations: room-level airflow prediction in a fast, intuitive environment.
- Minutes
- Room-level
- Free
Verified CFD
Detailed numerical analysis for critical applications, performed by EffectiV.
- Deep analysis
- ASHRAE 62.1
No complex CFD setup. No specialized simulation expertise. No waiting hours for routine design comparisons.
Assumptions and limits
What SelectiV predicts, and what it rests on.
SelectiV is a physics-informed air distribution design tool, not a CFD solver. Its predictions are subject to the assumptions and limitations of its modeling methods.
Built on
- EffectiV’s published performance data for each diffuser: throw, NC and pressure drop.
- Catalogue throws are isothermal. SelectiV applies the supply-to-room temperature difference to predict how jets rise or fall.
- Established air distribution principles, combined at room scale by physics-informed calculations.
Accounted for
- Ceiling height, room geometry and adjacent walls.
- Airflow rates and supply temperatures in cooling and heating, at minimum and maximum VAV airflow.
- Ceiling attachment and interaction between neighbouring jets, within the model’s scope.
What it is not
- A CFD solver: SelectiV does not solve the full airflow equations over a mesh.
- The 3D preview is an approximate reconstruction from the top, front and side views.
- Perceived NC is a room-level estimate. Velocities are predictions, not measurements.
Depends on your inputs
- Results are only as good as the inputs: dimensions, ceiling, airflow rates, temperatures, diffuser positions, doors and windows.
- What the model does not describe (furniture, partitions, local heat sources, obstructions) can change the real airflow.
When a project needs more (a critical application, indoor air quality, ASHRAE 62.1), Verified CFD analyses the room in detail: velocity, temperature, mean age of air, PMV/PPD, CO2 and Ez.
Explore Verified CFDBeyond individual diffusers
From air terminals to complete architectural air distribution.
Architectural perforated duct diffusers
Design complete BREEZ duct layouts in 3D, with sections, elbows, reducers and branches. Auto-Design can evaluate tens or hundreds of thousands of perforation-pattern candidates for each duct section.
Architectural duct diffusersComplex air distribution systems. Remarkably intuitive design.
Engineered for real operating conditions
One room. Multiple conditions. One optimized design.
A room doesn’t operate under a single set of conditions, and neither should its air distribution design. With SelectiV’s VAV and CAV capabilities, engineers define airflow rates and supply temperatures for heating and cooling, and Auto-Design considers them when evaluating configurations.
- Minimum airflow
- Maximum airflow
- Cooling
- Heating
- VAV
- CAV
A great design should perform beyond a single operating point.
The details that matter
Engineering insight, without the complexity.
Airflow performance
Predicted throw, spread and air velocity under specified operating conditions.
Thermal behaviour
How heating and cooling influence jet trajectories, air mixing and the occupied zone.
Acoustic performance
Individual diffuser NC and estimated room-level perceived NC.
Pressure drop
Static pressure information to support product selection and system design.
Engineering documentation
Detailed PDF reports of selections, room configuration, operating conditions and predicted performance.
Built for teams
Compare, rate, discuss.
Save alternate designs for every room, compare their airflow side by side, rate them, and leave pinned notes right in the 3D room.
Award-recognized innovation
Redefining what’s possible in HVAC design.
SelectiV’s recognition among the finalists in the Software category reflects a new approach to one of HVAC engineering’s most fundamental challenges: understanding air distribution performance before installation. And we’re only getting started.
Watch SelectiV in action.
Your first project
Your first design, in minutes.
Nothing to install. Here is the whole path, from an empty room to the PDF report.
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It runs in the browser, with nothing to install. Start a new room.
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Length, width and height, ceiling type, occupied-zone height and maximum NC; cooling and heating supply conditions (fixed, VAV or CAV); doors and windows.
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Position them yourself, or describe the goal: Auto-Design ranks thousands of layouts by throw, NC and perceived NC. Apply the one you choose.
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Velocity fields in top, front and side views, in cooling and heating, with the throw and NC of every diffuser. Compare alternates side by side.
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A PDF report of the selections, room configuration, operating conditions and predicted performance, ready for the design file.
What’s free
A free account includes
- The 3D room, with doors and windows
- Velocity fields in top, front and side views, cooling and heating, plus the 3D preview
- Auto-Design for diffusers, continuous linear slots and BREEZ perforation patterns
- VAV and CAV operating conditions
- Diffuser NC, room perceived NC and pressure drop
- PDF reports
- Design alternates, side-by-side comparison, ratings and pinned notes
Free for HVAC engineers and designers. No licence to buy, nothing to install.
Try it on a real room
Open SelectiV and follow these five steps with a room from your own project.
Your next design starts here
Better air distribution is now within reach.
No expensive licenses. No complex installation. No steep learning curve. Just powerful, browser-based design tools, free for HVAC engineers and designers.
Design the room. Explore the possibilities. See the performance.
Room First. By EffectiV.