Awesome ASCII skillz...

Detached
Code:
   ---------
  /         \
 /           \
/             \
|             |
|   House 1   |
|             |
|             |
---------------


Semi-detached
Code:
   -------------------------
  /            |            \
 /             |             \
/              |              \
|              |              |
|   House 1    |   House 2    |
|              |              |
|              |              |
-------------------------------


Terrace
Code:
   -----------------------------------------------------
  /            |             |             |            \
 /             |             |             |             \
/              |             |             |              \
|              |             |             |              |
|   House 1    |   House 2   |   House 3   |   House 4    |
|              |             |             |              |
|              |             |             |              |
-----------------------------------------------------------