Bifold door panels are supported on one side that is connected to the rollers while the other side has no support. This means that the panels can potentially drop or sag over time due to the weight of glass. The easiest way to identify a dropped bifold door is that it rubs on the sill or floor. Other signs can be difficulty in locking the handle of the bifold door or there may be a gap at the top of the door. (Sometimes, these two points, more often than not mean that the door has not been adjusted properly yet or the bifold panels need readjusting once a new building has settled over time).
Therefore, it is important to glaze the bifold doors properly. This method is known as heel and toe through which the glass is braced diagonally from corner to corner using setting blocks. This distributes the weight of the glass towards the side connected to the rollers (shown in the pictures below as hinge side).
Below is step-by-step guide to heel and toe our bifold doors properly.