Another way to say the same thing for inanimate objects without using 'whose' is: The car whose roof is black... The car with the black roof... The car with a black roof... The car that has a black roof...

"Whose" can also be used for animals. There isn't a natural-sounding equivalent for other things. Usually, people use a different (easier) sentence structure, for example, " The house which has a blue door", or "The house with the blue door".

TheFreeDictionary says: It has sometimes been claimed that whose is properly used only as the possessive form of who and thus should be restricted to animate antecedents, as in a man whose power has greatly eroded. But there is extensive literary precedent for the use of whose with inanimate antecedents, as in The play, whose style is rigidly formal, is typical of the period. In an earlier survey this example was acceptable to a large majority of the Usage Panel. Those who avoid this usage employ of which: The play, the style of which is rigidly formal, is typical of the period. But as this example demonstrates, substituting of which may produce a stilted sentence. http://www.thefreedictionary.com/whose