Radiata Pine Posts and Piling – types and uses

Posts and piles come in different shapes and sizes, each with a use specifically suited to it. This guide describes the best uses for the most commonly available types of posts and piles.

¼ Round Posts

These are created from one big strong round post cut vertically into 4, usually from older, larger diameter trees. Measurement is taken from the shortest face at the smallest end and are usually treated to H4. They’re cheaper than more robust posts and generally suitable for lighter work, ideal for running electric tape etc.

½ Round Posts

The half round post is stronger than the ¼ post but still relatively cheap, but still usually treated to H4. Measurement is taken at the smallest end and both face-size and thickness are counted in sizing. They have the advantage of a flat side, which makes nailing to them much easier

Peeler Cores

Peeler cores are the weakest available post and for now, we have stopped carrying them. They can be useful in olive orchards or as horse jumps, and are ideal for very small retaining walls or light fencing. Peeler cores are created from logs which have been peeled into fine veneers for use in plywood manufacture and the core that’s left over from the peeling process is the medulla (pith of the log) and not especially strong and at times not treated fully 100% to H4.

Square Posts

Square posts look great but cost more because of the wastage associated with removing the sides and squaring them. They’re excellent for use in fences and retaining walls and are treated to H4.

#1, #2, #3 and #4 Round Posts

These four post grades tend to be fairly light with #1 the heaviest of the four. They come from the tallest part of the tree and have different SEDs (small end diameter) and treated to H4. Measurement of post diameters will be given from the smallest diameter to the largest so that when purchasing, the smallest diameter is the least size you purchase. Posts represent debarked round lengths lacking any other kind of machined sizing. They are pressure treated to force chemicals into the posts to stop rot. 

Strainers – straining posts

Straining posts are large, heavier posts used at the ends and corners of fences and are designed to take the cumulative strain of the entire fence, which is why they need to be much bigger. Measurement is taken at the shortest diameter of the smallest end of the post and these are treated to H4.

The above posts are generally H4 treated (see our blog – Treated timber categories and how to work with them) and should last in the ground for up to 50 years.

House Piles

Piles are stronger, better quality posts, with no faults in them which can accept the weight and potential movement of a house (but also bridges/wharves, etc.). They are treated to H5 to sustain up to 100 years immersion in soil.

Anchor Piles

Anchor piles are premium quality very strong specially marked piling treated to H5 grade and are used to resist lateral loads. Ordinary house piles are used to sustain vertical loads. Generally five or six strategically placed anchor piles are used along with normal piles when building a house. 

Marine Piling H6

Marine piles are of various sizes and strength but typically stronger than piles intended for use on land. They are treated to H6 which enables their use in marine or aquatic settings. Marine and other aquatic piles need to be checked regularly for water-borne pests such as Teredo.

If you need help sorting out which posts or piling to go for to best suit your application, Renovation Warehouse always has a friendly face who can give you good advice. 

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Port Whangarei 0110

Phone: 0800-274-438 or 438-2887
Email: sales@renovationwarehouse.co.nz