Concrete tile and what fails first
A great many homes around Tampa Bay were built with concrete tile, and it creates the most misunderstood roofing situation in the region: the part you can see may have decades left while the part you cannot see is finished. On a tile roof, the underlayment is the roof.
Two materials, two lifespans
Concrete tile is a shell. It sheds the bulk of the water, takes the sun, and can last fifty years or more. Underneath it, a layer of underlayment does the actual waterproofing — and that layer is felt or synthetic membrane with a service life of roughly twenty to thirty years in this heat. When it goes, the roof leaks, and no amount of intact tile changes that.
This is why an owner can be told their thirty-year-old tile roof needs replacing and reasonably think they are being sold something. They are not — but the job being described is specific: the tile is lifted and stacked, the old underlayment stripped, new membrane installed, and the tile relaid with broken pieces replaced. The roof ends up looking exactly as it did, which is part of why the price surprises people.
What to ask on a tile quote
Three questions separate a serious tile quote from an optimistic one. What underlayment is specified — and there is a real difference between the minimum and a premium synthetic in this climate. What breakage allowance is assumed, since tile always breaks during removal, and what replacement tile costs if the original profile is discontinued. And whether the flashing, valley metal and vent collars are being replaced while everything is off — which is the only sensible time to do it.
One more consideration specific to Florida: once more than a quarter of a roof is being redone, code generally requires the whole assembly to be brought up to current standards. On a partial tile repair that grows, that rule can turn a patch into a full project, and it is better to know before starting than halfway through.