FAQ – What drainage is required for bi-fold doors?
There are two types of drainage methods that can be used for external bi-folds. These apply to both weathered and non-weathered thresholds. They are:
Face drainage. Water enters the lower chamber of the track and exits via a capped hole in the outer face. It is common place to then put an Aco drain in front of the door track which will route the water to a drain.
Concealed drainage. Water exits the bottom track through the polyamide break barrier and enters the top of the cill. From there, it travels through the front section of the cill and out of the very front edge underneath.
How rain water and surface water drains away from any part of your property is a site-specific requirement and should be reviewed by a qualified person.