Oh - absolutely adorable!
How about an attic window? Use a dark brown for the horizontal rows, a medium brown for the vertical rows, and a half square triangle (with the dark brown on the bottom left and the medium brown for the top right) for the cornerstones.
Here's an example of what I'm talking about only going to the left instead of the right:
http://www.quiltaholics.com/bom/attwin.htm