Thanks in advance,
MC
I think the bigger problem is semi-transparent stains work well on bare
concrete or concrete that was stained the same color. If you have
various colors already there, I don't think a semi-transparent is going
to work. The old colors will show through.
I thought roof tiles were actually clay or similar, with the color
contained throughout the material? Seems repairs should have been made
with matching tiles. If you must cover up what is already there,
I'd go with a solid stain, which is alos availabel at HD or most paint
stores.
Diane