You have a choice of two thresholds, the low aluminium and the pvc frame. The low aluminium is just 15mm high and creates a low step over when your door is open. The low threshold is suitable for disabled and wheelchair access and is Part M compliant. It is also colour matched to the door frame.

The pvc threshold means you will have a four sided door frame with the frame along the bottom, when your door is open you will have around 72mm of frame to step over. This provides the tightest and most thermally efficient weather seal as the door sits behind the frame on all four sides.

pvc thresholdlow threshold

Depending on your choice of cill and threshold, you will need to ensure the door clears the internal floor when it is open.

Internal Clearance - Distance from the underside of the cill to the bottom of the door