















Discover how Ventmann solutions can be integrated into your design.
VENTMANN ACOUSTIC BOX - INVISIBLE HVAC INTEGRATION
INNOVATIVE DESIGN
- Seamless & Quiet Performance
Integrates effortlessly with Ventmann linear slot diffusers, ensuring even airflow while the foam insert reduces noise for a discreet, comfortable indoor environment. - Easy, Flexible Installation
Features pre-scored knock-outs (75mm, 125mm, 160mm) for quick spigot attachment, allowing installers to fit the box efficiently without compromising design or performance. - Perfect Fit for Any Space
Available in multiple lengths (625mm, 1000mm, 1250mm) and width codes (A, B, C) to match your diffuser setup, providing an invisible HVAC solution that blends into any interior. 
ABOUT VENTMANN ACOUSTIC BOX
- Optimized Airflow & Noise Reduction
Designed for use with Ventmann linear slot diffusers, the Acoustic Box ensures even air velocity across the diffuser face while the integrated foam insert minimizes airflow noise for a quieter, more comfortable environment. - Flexible Installation
Comes with three pre-scored knock-outs (75mm, 125mm, 160mm) for easy spigot attachment. Installers can quickly secure spigots (supplied separately) with tech screws, making setup fast and adaptable. - Variety of Sizes & Codes
Available in lengths of 625mm, 1000mm, or 1250mm and width codes A, B, or C, matching perfectly with Ventmann linear diffusers to ensure seamless integration and optimal performance. 
Step 1
Line Diffuser Installation Instructions
Pre-position the ventilation duct in the ceiling 
void, above, through, or alongside the ceiling 
joists.  If required, purchase reducer(s) to suit 
the size of duct and spigots (by others). 
Step 2
Fit temporary batons with plasterboard 
spacers that are the same thickness as the 
final ceiling plasterboard sheet.  Where metal 
plasterboard rails are employed, suitable self
tapping screws will be required.
Step 3
Fit pre-assembled* diffuser, plenum box and 
spigot(s) on top of temporary batons.  Note 
that spigot (by others) is surface mounted on 
plenum using self-tapping screws and 
silicone. 
*Using screws provided
Step 4
Fix plenum to upper surface using proprietary 
fixings (Unistrut etc) (by others). Fix to 
plenum with self-tapping screws.  Adjust 
height of the plenum so that the face of the 
diffuser just touches the top of the batons. 
Step 5
Remove temporary batons and plasterboard 
spacers.  Measure and cut the hole in the 
main plasterboard sheet.   Lift the 
plasterboard sheet to meet the diffuser and 
fix in place as normal using plasterboard 
screws. 
Step 6
From the underside, use a jointing compound 
to fill the gap between diffuser and 
plasterboard. If required, move magnetic 
blocks to desired length and fix in place using 
jointing compound.  Sand and paint. 
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