Extrusion companies who design window profiles recommend that sashes are fully reinforced with galvanised steel, to provide adequate resistance against burglars.
This reinforcement is also needed to prevent profiles deflecting in windy weather and to strengthen the sashes so they are capable of carrying the weight of the glass. This also provides a strong, secure fixing for the handles, latches and other components.
Not every company complies with the manufacturing rules the extrusion designers lay down. Some manufacturers reduce costs by removing this reinforcement altogether. Others insert recycled plastic reinforcement sections, again to cut costs. We understand the importance of steel reinforcement. Although it drags down energy performance (which we regain using clever glass) you can be assured our windows are secure.