Defective Wooden stumps

The back of our house slopes away from the rest of the house. This is mainly due to some drainage problems a few years ago and the wooden stumps sank a bit.

Looking at inserting some fibre cement packers in between stump and bearers to try levelling things out

I'm sure I'll find some stumps that will need replacing. How would you judge at what stage a wooden stump needs replacing?

dig down beside the stumps about a foot deep and see if the timber is rotten.

Jaffa how far has the house sunk at the furthest point?

Give the stumps a knock with a hammer, you can often hear a hollow or solid sound depending what the condition is under the surface.

sunk about 20mm

Should be able to get that out as long as it isn't going any further.