Roof Leak Wind Driven Rain

Wind blown rain leaks.

Roof leak wind driven rain.

This will stop the rain getting under and causing roof leaking by wind driven rains. It this is the case you need to create a breathable shield to slow the driving rain drops while still allowing air flow. However this is not entirely the case since there are leaks that can be caused by a mixture of wind and rain that are called wind driven rain. Wind driven rain will batter your roof and water will escape through any cracks no matter how small they are.

The only means of prevention is to install membranes under the roofing. No sarking to catch leaks driven in by heavy rain leaking low pitched tile roofs with sarking heavy rain and blockage causing the valleys to overflow. Wind driven rain can cause a problem and very difficult to fix. An exterior door facing the north with little roof overhang is a prime candidate to leak.

One common myth is that roof leaks are just the calm before the storm and is a tell tale sign to a larger problem that deals with shingles faulty fastenings or even unsealed gaps. Once again you could actually have a good roof and wind will drive water up and under your roofing materials. And on occasion a hard driving rain with whipping wind will cause roof vents to leak water. Yes water can flow uphill when blown by wind.

In other words water may not flow down to eaves on the windward side but instead can be driven up the roof to the peak. Often a roof can be in perfect condition but because the wind drives the rain across and upwards it can get under the eave and under the roof. Further during a hurricane wind can blow rain water up the roof in sheets. Cracks in roof tiles need not be huge to cause a significant leak.

Hemming the edges of the roof means bending the underneath to an angle of 180 degrees. The most common reasons why roofs only leak during heavy rain are. Hairline cracks in tiles or splits as they are sometimes called cause leaks too. Roof vents can let hurricane driven rain into an attic because most vents are not designed to resist hurricane forcefully driven rain.

In that path it passes vents on the roof. Hemming the roof edges. If your roof vent leaks during heavy rain the rain may be blowing up under the hood and into the vent.