2UL Ventilation Louvres

2UL is a double bank louvre system which provides high airflow performance with a good degree of rain defence.

When rain defence is needed, we recommend the use of either 2UL or 3UL. When rain defence is not of primary importance, we recommend the use of 1UL.

Colt Universal Louvre can be uniquely configured to provide the solution to your needs.

Here are some of the features and benefits of Universal Louvre:

Highly aerodynamically efficient – this reduces air resistance, allowing the plant and the aperture to be minimised thereby saving running costs.

Enhanced rain defence performance - 2UL and 3UL versions have high resistance to rain ingress. Unlike other louvre types, Colt 2UL and 3UL panels have efficient drainage paths into their hollow section mullions, which in practice further increases their rain defence effectiveness.

Durable and maintenance free – UL is completely made from corrosion resistant materials.

Thermal expansion of the louvres enabled – the louvres are clipped (and not riveted or screwed) to structural supporting mullions.

Easy to install – UL can either be delivered to site pre-assembled or as a kit of parts

Aerodynamic performance

  • Universal Louvre 2UL/SH - minimum performance coefficient (Cv) of 0.308 (inlet) and 0.25 (extract). This is equivalent to Class 2 to EN 13030.
  • For data on DH (deep) versions, please contact Colt.

Rain defence performance (to EN 13030)

  • Class A - up to 1m/s suction velocity
  • Class B - up to 2.2m/s suction velocity
  • Class C - up to 3.0m/s suction velocity
  • Class D - up to 3.5m/s suction velocity

Double bank louvres provide high airflow performance with a good degree of rain defence.


  • Tested to EN 13030:200


For further details, view the PDF