When the rain is heavy and in huge doses it can make damage on the roof and make it leaky. In the interior we will notice that when the drops will penetrate trough the ceiling and usually drip down on your favorite furniture.  That is the emergency sound that means you must find the source and try to fix it. If there is still raining you should only find the leaky spot on the roof and put a bucket to collect the water. If there is no rain, you can dry and fix the damage.  Usually, the leaking spot is not actually the damaged one. You should search for it more above on the roof, especially between the broken, or missing shingles; where nails have worked loose; or through corroded or poorly sealed roof flashing around vents, skylights, or chimneys or along the intersections of roof planes. More about this, from the link bellow.

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