A tile roof can last for 50 years or decades longer, if proper installation methods are followed and critically important elements are incorporated. Top flashing is one such element that’s essential to keep a tile roof watertight.
What is the Purpose of Top Flashing?
For a tile roof to shed water properly, rain must either run on top of the tiles, or be directed on top when it hits areas where other surfaces intersect with the tile. Transitional top flashing is crucial to bridge the gap in these areas on a roof, which can include penetrations for chimneys, vent pipes, roof vents and skylights, at valley junctures and head walls or roof-to-wall and pitch transitions.
How Top Flashing Impacts Tile Underlayment Performance
Correctly installed top flashing is the single biggest differentiator between a tile roof that fails prematurely and one that performs as expected. With the flashing in place, water stays on top of the tile, so the underlayment is not relied upon daily in order to keep the building dry.
The underlayment frequently used on tile roofs consists of a fiberglass mat saturated with asphalt for waterproofing. If rain runs over the underlayment repeatedly, it rapidly erodes due to a process called “oil migration,” where the oils in the asphalt escape the mat and rise to the top of the water. This erosion occurs faster wherever water flow is greatest, such as valleys, around protrusions and at valley bases. Eventually, the underlayment becomes dry, brittle and prone to cracking.
Top Flashing Can Sometimes Save an Existing Roof
When top flashing is missing or incorrectly installed and underlayment deterioration leads to a leak, it often occurs in the areas of increased water flow resulting in a serious water intrusion that causes more than a small ceiling stain.
When unsuspecting managers or owners get fed up with the constant headache of repeated tile roof repairs on their Naples property, they may end up replacing the roof unnecessarily. If the same flawed installation techniques are used, they’re right back in the same situation.
Since tiles can last a lifetime, we can sometimes save a roof that’s been installed for years if an inspection reveals that the tile itself isn’t leaking. Simply having top flashings properly installed can halt decay and allow a tile roof to deliver the performance expected. For skilled tile roof repairs in the Naples area, contact us at Kelly Roofing.Read: Why Not to Rely on Tile Underlayment