how do i re surface or paint my cement tile roof?

There are paints you can use or companys can do this for you. I always feel they look a bit false and tacky though. Sometmes with sprayed on paint it can seal the joints and gaps in the tiles in an undesirable way and lead to leaks you didnt have before.
Personally I'd balance the cost of this with a new roof.

Kel
June 2009