Architectural aluminium systems supplier Kawneer has further enhanced its AA540 window range, which combines value for money with a BRE Green Guide A-rated frame with side-hung and bottom-hung variants of its tilturn system. The new AA543 sidehung and bottom-hung open-in variants join the original AA543 tilturn (tilt for ventilation and turn for cleaning) and an AA541 casement and AA542 pivot …