"YT" wrote in message
...
I just bought my first house a couple months ago, and I'm looking to hire
someone to lay some new sod (something I've never done before), and was
wondering if it's ok to just lay sod over a layer of topsoil. My house sits
on a hill with an ~20% grade, and a lot of the soil seems to be eroding, so
I want to try to stop the problem by laying new sod. The contractor I
talked to today said that because there will need to be new topsoil thrown
down (~4 inches), tearing up the old sod is a waste of time, and money. He
said that if they just throw the new sod on top of the new topsoil, that
will work fine. Does this sound right, or should I find someone else to do
the job? Will this be enough room for the roots to grow? Thanks.

You might get away with soil adding in 1" steps, allowing the sod beneath to
take hold each step. Do use a row of sod perpendicular to the elevation to
help retain the soil every 4 feet or so. Or, 1" gravel as an alternative.
The last 1" of soil don't add any retention material. However, this is
prohibitively expensive on the hired labor end. You'd probably have to do
it yourself.
--
Jonny