Why did the White House experience water damage ? 1.
It is made of granite which is strong.

2. It is made of sandstone which is very porous and is easily penetrated by rainwater

3. It is made of non-porous sedimentary rock

The White House building is made of sandstone which is very porous as a result water is easily penetrated inside it which causes damage and make the walls of building weak.

The White House is made of gray-colored sandstone that is brought from quarry in Aquia, Virginia. The north and south porticos of white house building are constructed with red Seneca sandstone brought from Maryland. These sandstones are porous in which rainwater is easily penetrated in it that cause damage to the white house building so it is concluded that the building is made of porous sandstone.

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