A weather bar (also known as a rain deflector or drip trim) is a protective strip fitted to the bottom of an external door. It guides rainwater away from the door threshold, helping to prevent water ingress whilst also reducing draughts.

A weather bar creates a drip edge at the bottom of the door that guides rainwater away from the threshold. Instead of running beneath the door, water is directed away from the doorway, helping to prevent water ingress.

A weather bar is recommended for most external doors, particularly those exposed to the elements. It helps reduce water ingress beneath the door while helping to reduce draughts, making it a simple and effective upgrade for older or replacement doors.

Weather bars are fitted horizontally to the external face of the door, just above the threshold. Most can be cut to length to suit narrower doors and are supplied with the required fixings. The exact fitting method varies depending on the design, so always follow the manufacturer's fitting instructions.

Most weather bars are suitable for uPVC, composite, timber, aluminium and steel external doors. Some designs are suitable for inward-opening doors, outward-opening doors, or both, so always check the product specification before purchasing.

Weather bar, rain deflector and drip trim are different names for the same type of product. Although profiles, finishes and fixing methods vary, they all perform the same function of guiding rainwater away from the threshold to help prevent water ingress and reduce draughts.