Choose a fence post cap that matches your post's cross-section, with common sizes fitting 70×70, 90×90 and 100×100 mm timber posts. Measure the actual post width and depth, as sawn timber can vary slightly from its nominal size. Some caps have a slightly oversized skirt or a flat top that overhangs the post for better water run-off.

The main fence post cap styles are round pyramid, square pyramid and ball-top, and the choice is mainly aesthetic. Pyramid caps give a classic, low-profile finish and shed water efficiently, while ball-top caps add a decorative feature-post look. All styles perform the same protective function of covering the post top.

Yes, galvanised steel fence post caps are weatherproof and resist rust through a zinc coating that withstands rain, frost and sun. This makes them suitable for permanent outdoor fencing without repainting. Galvanised metal caps also add durable protection to the vulnerable top of a timber post.

Fence post caps are fixed by placing the cap over the post top and securing it with galvanised screws or nails through the skirt, or with exterior adhesive. Metal caps usually have pre-drilled or punched fixing points, while some press-fit or slot-on designs need no fasteners. Make sure the post top is cut level so the cap sits flat and sheds water evenly.