Can concrete tiles go porous

yes they can. over time they will and also with age start to crack. The life expectancy for a concrete tile roof is marketed as a 50 years. but the under lay and batten system, even if good material and the proper installation procedure was used, it wont last that long and will probably have to be replaced generally around 30 to 40 years.

yes for lots of different reasons.

Yes.

concrete is porous to a certain degree are you talking about roof tiles?

Hello Estimator The answer to your queston is yes, concrete roof tiles do become porous over a period of time hope this helps Gary Griffiths