Regularly cleaned gutters protect many key components of the home, including the foundation. Clogged gutters put the foundation at risk, storms come and go, rainwater runs amok, pooling around the base of the home and seeping into the ground, where it exerts intense pressure against the foundation.
After a while, due to the pressure, the foundation begins to crack, allowing water to enter the basement resulting in extensive and expensive to repair damage.
Tthe foundation may ultimately fail if the situation does not get corrected, leaving the home vulnerable to a cave-in or collapse—a catastrophe.
When gutters malfunction, water gets to parts of the home that were never designed to withstand exposure to that much moisture.
Windowsills and door jambs are often the first to buckle. Mold poses a legitimate health hazard, particularly if anyone in your household suffers from allergies.
“If you allow clogs to render your gutters ineffective, it could take only one heavy storm to compromise or even erode your landscaping.”
Original Source: http://www.bobvila.com/slideshow/5-ways-clogged-gutters-are-destroying-your-home-50590?slide_name=weak-foundations&bvsp=lg