Tile roofs last forever, don’t they?
One question that continually arises with respect to tile roofs is whether or not any reserve should be established for replacement of such roofs since the roofing material itself is considered to be a lifetime component. Our 20+ years of experience has shown us that while the roofing material may last a lifetime, the roof underlayment material is not a lifetime component. The underlayment material will typically last anywhere from 20 to 30 years before it loses its waterproof integrity. This happens because the material is either damaged by ultraviolet rays where they penetrate at the margins of the roof or the material simply becomes old and brittle and cracks, thereby allowing water to penetrate the building structure below.
As a consequence we do recommend establishing a reserve for replacing title roof underlayment on a 20 to 30 year cycle. Experience also shows us that tile breakage factors can range from 10% to 30% during the roof removal and replacement process. The net effect of this is that the removal and replacement process is roughly equivalent to the cost of installing a new roof.