Groove and tongue board vs 5/8 plywood sheathing

Which one is better??
tongue and groove board or 5/8 plywood.

Can I mix them???
House had tongue and groove boards,must of them are good.

Thanks.

Hi,

The tounge and groove are 3/4" thick. Use 3/4" plywood if you cannot find the boards.

It is easier replacing with like kind.

ussually when they use tounge and groove wood for deckin its for an open ceilin as well.
if you can see the t&g from underneath , you want to replace that area with t&g.
if ya cant see it then use plywood.

gweedo.

What gweedo said, except I will add that I would use 1x wood planks in areas where you are trying to replace only a board or two, because plywood usually doesn’t do too well if you are installing narrow strips of wood.

Thank you guys.