5 reasons why actuated windows are not a good idea1. 5 reasons why actuated windows are not a good idea
Windows and actuators do not make a complete ventilation system!
You may think that fitting an actuator on a window will
make a cost effective solution for smoke and natural
ventilation, but that is not the case. Here are 5 reasons
to avoid actuated windows.
The window and actuator may be incompatible.
These two ‘off the shelf’ components are often supplied
by two different parties in the construction process.
Rarely is the compatibility of the components
considered adequately. For example, a window with
sliding/scissor hinges has a vertical action, whereas an
actuator’s chain drive would normally operate in the horizontal plane. If the motor drives too far, the
hinge mechanism may lock up with the potential for damage when the window tries to close. Similarly,
a UPVC or timber framed window may not have the strength in the right areas to take the loads being
imposed by a high powered actuator, particularly if it is badly aligned. And, if you run into such a
problem, where does responsibility for the incompatibility lie?
A window with an actuator is not tested as assembly. Compared to ventilators, a window with an
actuator won’t generally be tested as an assembly. This is important because the hinges and seals are
not designed for continuous opening and closing by mechanical force. By it not being tested as an
assembly, you won’t find out how well – or how badly – it will work over time. You don’t want it to fail
when you most need it during a fire!
You won’t necessarily achieve the right area. Just fitting actuators on your windows means that you
won’t necessarily be relying on a properly designed ventilation system: how can you be sure that the
right area is being achieved with your simple window?
Excessive cost of controls. A contractor will tend to supply an actuator at the lowest price, so you
might get a 24V 6A actuator. This component doesn’t cost much, but it has a high power demand.
Control issues may arise in this situation, as a higher power demand can often lead to needing large
back-up power supplies (and consequent long-term maintenance requirements), as well as restrictive
cable lengths.
Ensuring good control of opening. Are you sure that your actuated window can provide proportional
and controlled opening, or is it just open/close? For effective ventilation, you need a system that has
the ability for modulating control.
The effective and safe solution? Ventilators
Purpose designed and tested. Ventilators are designed precisely for smoke and natural ventilation.
Norms in Europe require them to be to tested to at least 1,000 cycles for smoke and a minimum of
10,000 cycles for day-to-day ventilation.
Tested as one assembly. Such ventilators are tested as one assembly to withstand pre-determined
wind loads and snow loads (if they are not installed vertically), for air leakage and for deflection to the
© 2013 Colt International Licensing Ltd.
2. relevant standard. The hinges and seals are selected to withstand the forces of continuous opening
and closing.
A larger free area. A louvred ventilator (which is nearly always fitted with an integrated actuator) will
generally provide a larger free area than a single pane window for a given size of opening.
A safer opening. A louvred ventilator operates more safely, being able to restrict ingress and egress,
as the opening aperture can be determined by selecting the number and size of louvres. This is a
particular advantage in education establishments.
Assured modulating control. The controls and actuators can be selected to provide the ability for
modulating control.
They look good. The actuators are integral to the unit, so they don’t look like an afterthought added at
a later date.
A guaranteed product. There is a single line of responsibility for the entire system, guaranteeing the
service it is meant to provide.
Conclusion
While fitting actuators on windows may seem like an attractive low-cost solution, you should resist the
temptation and choose purpose-designed ventilators.
If you would like to know more, why not contact us or read about natural ventilation on our website.
© 2013 Colt International Licensing Ltd.