20mm vs 40mm gravel?

[Steve06]

Hi,

We have 8 x wooden garden fence posts that have been standing in wet soil/clay.

I have dug around them to allow them to breathe and intend to fill in the holes with gravel stones.

I do not know if I should should use 20mm or larger stones?

Any thoughts please and any other suggestions to protect these wooden post as best as possible?

Thank you very much.

Steve

[JohnMo]

Concrete or postcrete, mix it well as you add to make sure no water pockets. Level just about ground and slope top away from post so any water naturally runs away.

[Russell griffiths]

What for, is this to fix them in position, if so do as John said and concrete them in. 
if they are fixed to the wall and you just want drainage around them, then cut them off at ground level, they don’t need to be in the ground if the wall is holding them up. 

[Steve06]

Hi, 

The posts are already fixed in position against a rear garden retaining wall so I do not want to cut them and possibly add more pressure against the wall, this is as you said a drainage issue to prolong their life. 

One of the 8 holes has filled with water whilst the others are all dry; this hole is not on either end which seems strange/worrying? 

I am now thinking I should add a subtle concrete slope away from the wall and remove ALL the soil from against the wall and add large gravel stones. 

🤔

 

 

[Conor]

Water logged spots don't rot, oxygen is needed, so they'll rot just above the ground. If you replace the soil with stones, they'll rot here instead as there will be air there. 

 

All the water is coming from below the retaining wall. It's a spring effect. The wall acts like a dam, water is forced under, then up out at the other side.

[Steve06]

Thank you Conor,

I believe you have hit the nail on the head🙏🏻

There is talk that our stretch of properties may have natural springs around them.

Should I consider another weep hole added to this part of the wall, unfortunately our current weep holes are only 40mm wide?

I am not a builder but is there anything I should be doing?

Many thanks, Steve

Edited April 30 by Steve06