Not sure I see your floor profile: you say 1/2" plywood (first yellow light), then tar paper (why?) (second yellow light) then 3/4" particle board (third yellow light) THEN vinyl, then luan? Do you mean to say you're walking on luan?
You go on to say your particleboard is sandwiched between tar paper and vinyl...so where's the luan in this statement?
Know what? whereas I am sure you could put tile on top of all these different substrates, I just see too many yellow lights flashing at me - not red lights but enough caution warnings to make me think that there wouldn't be a cumulative effect that isn't pointing to a solid floor. Again, I may be wrong, but seeing that, I'd do a deflecto test and see what that gives. Besides, you're starting to get quite a high floor there...if either the deflection or the height gave me one bit of grief, I'd say there's too many question marks for a tile job that lasts, so I'd take out everything down to the plywood. The vinyl already there means that the tile job may not last over 5 years.
And I say that not with one particular reason for it - just a gut feeling.:yes:
You go on to say your particleboard is sandwiched between tar paper and vinyl...so where's the luan in this statement?
Know what? whereas I am sure you could put tile on top of all these different substrates, I just see too many yellow lights flashing at me - not red lights but enough caution warnings to make me think that there wouldn't be a cumulative effect that isn't pointing to a solid floor. Again, I may be wrong, but seeing that, I'd do a deflecto test and see what that gives. Besides, you're starting to get quite a high floor there...if either the deflection or the height gave me one bit of grief, I'd say there's too many question marks for a tile job that lasts, so I'd take out everything down to the plywood. The vinyl already there means that the tile job may not last over 5 years.
And I say that not with one particular reason for it - just a gut feeling.:yes:
