For ventilation and cleaning from inside, windows open in different ways. The most common that are used in this country today are the side and top hung casements that are hinged from the side or top and open out. Also know as ‘side openers’ and ‘top fanlights,’ these windows make up the majority of what you will see in Britain down most streets.
Each frame material will have a standard push-out option. The most popular hinge for these openers is the friction hinge and fixed top and bottom to side casements and to the sides in top openers. Their name helps to describe the job they do by holding the opener in an opening position without the need of a ‘stay.’ These friction hinges can also incorporate ‘restrictors’, ‘egress’ for full aperture opening and ‘easy clean’ for access to the front of the opener. ‘Butt’ hinges can also be used but will require some kind of control against blowing open and the opening casements cannot be cleaned from inside.
We started with the simple ‘cock-spur,’ this handle is fixed to the opening frame and has a right angle section that overlaps onto the main frame to lock. It is crude but was the only handle available 30-years ago. I would only now advocate the cockspur when used on steel frames. All other windows should use ‘Multi-point’ security systems. The function of the handles on these systems is to turn a gearing system. The best of which also incorporate shoot bolts at each end as well as mushrooms or cams along it’s length.