Missile Teams indoors?

[hoplitis]

A thought,
firing a missile (say an ATM) from inside a building isn't so easy as it sounds. There must be ample space for the "gas plume" to expand normally without burning the crew! Not possible in a bedroom! Possible if firing from a warehouse, though.On the other hand when you have a Stinger section in a building it is logical to assume that it's located on the top. So probably the same assumption must be made for all missile firing inf units.
And this raises a more general question concerning infantry in buildings. Are the "searching/defense modifiers" based on the assumption that the unit is "in" the building?
Just curious!