jmc

The areas of the tops of $A$, $B$, $C$, and $D$ in the figure formed has sum $1+1+1+1=4$ as do the bottoms. Thus, the total so far is $8$. Now, one of the sides has an area of one, since it combines all of the heights of $A$, $B$, $C$, and $D$, which is $1$. The other side is also the same. Thus the total area now is $10$. From the front, the surface area is half, because if you looked at it straight from the front it would look exactly like a side of $A$, with a surface area of half. From the back, it is the same thing. Thus, the total surface area is $10+\frac{1}{2}+\frac{1}{2}=11$, or $\boxed{11}$.