Home > Companies > Lorient Polyproducts Ltd > Non-Vision Style Grilles – LVN20 and LVN25

Non-vision style air transfer grilles.


  • Can be used to provide resistance to fire and hot smoke of up to 60 minutes in fire rated doors.
  • Angled slats to ensure complete visual privacy.
  • Supplied in two halves to accommodate different thicknesses of doors.
  • Complete seal achieved in approximately five minutes when tested in accordance with BS 476: Parts 20/22.
  • Allows bi-directional air flow.
  • Easy to keep clean.
  • Contains no moving parts.
  • No site testing is necessary.
  • Holds CERTIFIRE CF564 certification.

Related literature

The following content references this product:

Standard product features


  • LVN20: Two pieces, 20 mm thick.
  • LVN25: Two pieces, 25 mm thick.
  • LVN20S: Two pieces, 20 mm thick.

Free area:

  • 30% approximately.



Grilles are available in a range of widths and heights from 100–600 mm in 50 mm increments. Larger sizes can be produced dependent upon application - please refer to Lorient's Technical Department.

Smoke control system:

The LVN20S is designed to be used with the Talkback smoke control system. The Talkback system can control up to sixteen dampers/ shutters and features a status monitoring display.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-25-38/330 Fire-resisting air transfer grilles

Product specification

An important note about specifying



Lorient Polyproducts Ltd


+44 (0)1626 834252

Product reference

[Lorient intumescent fire damper, non-vision style Ref: LVN20]
[Lorient intumescent fire damper, non-vision style Ref: LVN25]
[Lorient intumescent fire and smoke damper, non-vision style Ref: LVN20S]

Fire resistance

[30 minutes]
[60 minutes]


[Not required]
[As drawing ___]
[200 x 200 mm]
[300 x 300 mm]
[400 x 400 mm]
[450 x 450 mm]
[500 x 500 mm]
[600 x 600 mm]




 - Type:
 - Finish:
[Timber, ash]
[Timber, beech]
[Timber, ramin]
[Timber, utile]
[Timber, Columbian pine]

Fitting: Screwed and bedded in Lorient intumescent mastic.

 - Mastic colour:

Smoke control system

[Not required]

Manufacturer details

Endeavour House,
Fairfax Road,
Heathfield Industrial Estate,
Newton Abbot,
Devon, TQ12 6UD
Tel +44 (0)1626 834252
Fax +44 (0)1626 833166
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