Arens International shares its expertise in automated windows and
natural ventilation systems to help designers develop accurate specifications
for their projects.
There are several important considerations to be taken into account during
the design phase of the project. These include window actuators, window sizes,
fastenings, window openings and locations, stays and hinges, mechanical and
electrical specifications, and cabling.
Window actuators
Arens recommends its chain and linear actuators to enable manual
operation of high level windows and louvres for natural ventilation; provide a
fully automated natural ventilation system; and facilitate natural and smoke
ventilation systems.
Window sizes
Awning sashes should ideally be at least 500mm high to avoid the need
for chains to be shortened. Windows should also be 450mm wide or greater to
ensure there is adequate space for the actuator to be mounted. Custom solutions
are available from Arens for smaller windows, but early consultation will be
required. For designs incorporating wide sashes, it is recommended that any
window greater than 1200mm should have two points of attachment to avoid
bending or twisting of the frame.
Fastenings
High wind loads can cause some fastenings to detach from timber and
aluminium sections. This is an important consideration in coastal and exposed
locations as well as multi-level buildings. If the project incorporates any
form of displacement air conditioning, it can lead to increased pressure on the
windows and attachments. Appropriate fastenings must be selected after due
consideration of these factors.
Window openings and
locations
Operable windows at high levels reduce a number of risks that may exist
with lower level windows, including lower risk of entrapment as they are out of
reach; reduced security issues and minimised risk of intrusion from night
purging; and avoidance of draughts, particularly in the cooler months.
Stays and hinges
The capabilities of the hinges must match the desired degree of opening.
For example, if top hung hook hinges are being used, the chain in the actuator
will need to be restricted. When stays are selected for awning sashes, their
travel must match or exceed the chain stroke of the selected actuator. Key
considerations also include use of non-friction stays or hinges and avoiding
stays with rubbing blocks.
Co-ordination with
mechanical and electrical specifications
When choosing electric actuators for windows, it is essential to
coordinate with mechanical and electrical specifications such as how they are
to be switched and powered, where the windows are located, the number and
location of GPOs, and how the cabling is to be brought through the window sill.
Cabling
The cable dimensions required will be determined by
both the number of actuators and the length of the run.
