"Percival P. Cassidy" wrote in message
...
We have some retaining walls built using railroad ties. I don't know how
long they've been there, since they were already in place when we moved
in, but they are beginning to look as though it's time to replace them. If
we replace them with new (actually old) railroad ties, how long are the
new ones likely to last? What kind of timber is used for railroad ties?
Anything we can do to make them last longer? -- creosote? The bottom
course is actuually below ground level.

We are thinking seriously about using interlocking concrete blocks
instead. Any thoughts on those?

Perce

Around here (Atlanta), they sell different grades of used railroad ties.
I'm sure the better ones last a little longer, but after 15 years, most RR
tie walls start looking pretty ratty, and after 20 years, it would probably
be replacement time.

The interlocking blocks are a good solution depending on how high you want a
wall. Some of the smaller ones they only recommend for 2' or 3' walls.
However, there are bigger, heavier ones that can go substantially higher.
If you hire the work done, this is a fairly expensive option.

Poured concrete is another solution.