Do you need bitumen paint when concreting H4 sleepers?

[Graeme50]

I am planning on using H4 treated pine sleepers as retaining wall posts.

I understand that bitumen paint is recommended for the portion of the wood going into the ground.

I was wondering that if the ground portion was going to be fully concreted in, is bitumen paint still necessary?  My thinking is that it is not because the concrete would provide the barrier between the wet soil and the post.

Do people agree?  Thank you in advance. 

[EricL]

Hello @Graeme50 

Think of the bitumen paint as a moisture barrier, not only does it keep water out, but it also prevents incidental moisture produced by hydrostatic pressure when water passes through the cement footing from getting through to the timber post. You have to remember that concrete is porous and will let water pass through. Put simply it keeps the timber dry, and this extra protection will extend the life of the post.

If you have any other questions we can help with, please let us know.

Eric

[Graeme50]

Great Eric,

You have changed my mind on this.  Thank you.  I will definitely use it on my retaining wall posts.