Sealing hardwood end grain posts - exterior

[AndrewHerrick01]

Hi there... I live in Sydney and have some hardwood (blackbutt) posts with exposed end grains. I did them years ago and a few have rotten through as I never sealed the end grains properly. I am now replacing some and want to make sure I do it properly this time so I don't have to keep replacing them every five years.

I have read about special end grain sealing waxes and was hoping someone could recommend one or give me tips on how to use.

Thanks so much!

Andrew

[double.d]

Are the posts a feature for a pergola or similar?

If they are not a feature then good old sump oil is the best.

[Chesand]

There is also Bitumen Paint.

[aldav]

I assume you're talking about the top of the posts not the bottom? The main thing that you can do to prolong the life of the posts is to stop water sitting on the end grain, cut them to a point. The point can be fairly blunt it only needs to be enough to allow the water to run off. I don't know of anything that you can treat the end grain with, that offers significant protection, that won't be pretty unsightly.