NSHEV Glass Louvre


Economical, ecological and aesthetic louvre window for smoke ventilation.

Features and Benefits:

  • NSHEV certified in accordance with BS EN 12101-2.
  • Programmable electric drive functions through SCS software.
  • Available in a range of sizes.
  • Provides good thermal performance.
  • Additional passive and active anti‑trap protection system for the main closing edges with reversing function.
  • Can be glazed into curtain walling or directly into structural openings.

General information


Insert requirement, 2500 mm maximum frame width.

Uniclass 2015

Pr_70_65_04_56 Natural smoke and heat exhaust ventilatorsPrimary

Specification data - Natural smoke and heat exhaust ventilators

Product Reference

NSHEV Glass Louvre FLW 32

32 mm depth, up to 1.1 W/m²K U-value (triple glazed).

NSHEV Glass Louvre FLW 40

40 mm depth, up to 0.8 W/m²K U-value (triple glazed).


Insert requirement, 2500 mm maximum frame width.

Louvre blades




Insulated aluminium panel



Insert requirement, available 200–450 mm for FLW 32 and 250–500 mm for FLW 40.

Glazing adapters

17 x 32 mm

For FLW 32 only.

17 x 40 mm

For FLW 40 only.

25 x 32 mm

For FLW 32 only.

25 x 40 mm

For FLW 40 only.

Special order

Insert requirement.





Standard product features


Louvre frames have mitred corners with internal brackets, and are screw-fixed. Louvre blades are centre-pivoted and close flush with the external vent frame.

Frame construction:

Thermally broken aluminium extrusions. Frame sections have mitred corner with internal brackets and are press-formed.

Frame depth:

  • Louvres: FLW 32: 49 mm; FLW 40: 51 mm.
  • Vent: FLW 32: 77 mm; FLW 40: 85 mm.

Visible frame width:

  • Louvres: FLW 32: 21 mm; FLW 40: 28 mm.
  • Vent: FLW 32: 20/ 40 mm (horizontal/ vertical); FLW 40: 40 mm (horizontal and vertical).

Louvre blades:

23–40 mm thick, includes ethylene propylene diene monomer (EPDM) gaskets.


Concealed rack and pinion mechanism provides easy to use, maintenance free, smooth and synchronized operation of the louvre blades.

Technical characteristics:

  • Barrier load: Tested BS 6180.
  • Impact resistance: In accordance with DIN 18032-3.
  • Security (to BS EN 1627): RC2.
  • Coefficient of discharge: Cv. 0.57 (maximum).
  • Wind load classification: Up to WL 3000.
  • Resistance to heat classification: B 300-E.
  • Reliability classification: Re 1000.
  • Low ambient temperature classification: T (‑05°C).
  • Air permeability (to BS EN 12208): Class 4.
  • Watertightness (to BS EN 12208): Class 7A (FLW 32) / Class 8A (FLW 40).
  • Tested sound reduction (Rw): 41 dB.

Third party certifications

  • NSHEV: Certificate: In accordance with BS EN 12101-2

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