Home > Companies > Renson Fabrications Ltd > Aluminium Louvre Grille 421

Framed, inclined blade, single bank, fixed louvre aluminium ventilator, for wall recess mounting.

  • Enables secure, weather resistant ventilation with exclusion of insects. Physical free area: 49 %.
  • Aluminium profiles with choice of finish. Blades at 50 mm centres.
  • Suitable for insertion into wall openings from exterior. 40 mm (maximum) flange overlap.
  • 4 mm external flange projection.
  • Choice of internal reveal fixing.
  • Dimensions (minimum): 150 x 150 mm. Made to measure.
  • Panel thickness: 50 mm.
  • Water tightness at wind speed 1 m/s: Class D (low), without water channel.

Similar models:

  • 411 - Available for lighter duty, with superior watertightness.
  • 421R - Available for round apertures.

Related literature

The following content references this product:

Standard product features


Aluminium alloy: AlMgSi 0.5 to DIN 1748.

NBS Specification

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This product is associated with the following NBS Create clause:
45-25-50/305 Aluminium louvre panel units

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Renson Fabrications Ltd


+44 (0)1622 754123

Product reference

[Aluminium Louvre Grille 421, rectangular]
[Aluminium Louvre Grille 421, round]
[Aluminium Louvre Grille 421, self-assembly]


[Single panel, aperture (w x h x wall thickness), ___ x ___ x ___ mm]
[Single panel, to outer edge of frame (w x h), ___ x ___ mm]
[Multiple panel, as drawing ___]
Requires coupling bars.


Nonstandard option. Required for panels larger than 3 m².
[Brackets type 1428]
Standard option. Screw fix to reveal.
[As drawing ___]

Finish (aluminium components)

[Anodized, bronze]
20 µ. Type E6/ EV1 to DIN 17611.
[Anodized, natural]
20 µ. Type E6/ C34 to DIN 17611.
[Polyester powder coating, RAL colour ___, sheen ___ %]
60–70 µ.
[Polyester powder coating, Syntha Pulvin colour ___, sheen ___ %]
60–70 µ.

Other requirements

[Coupling bar]
For multiple panel unit.
[Drainage profile]
Projecting drip for fixing to bottom flange.
[Dust filter]
With aluminium frame. Fixes to interior of louvre panel.
[Mesh, 2.3 x 2.3 mm]
Standard option. Grade 304 stainless steel.
[Mesh, 6 x 6 mm]
Nonstandard option. Grade 304 stainless steel.
[Water channel]
For insertion behind bottom louvre. Projecting internal collection channel with drip to exterior.

Manufacturer details

Fairfax Units 1 - 5,
Bircholt Road,
Parkwood Industrial Estate,
Kent, ME15 9SF
Tel +44 (0)1622 754123
Fax +44 (0)1622 689478
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