Every corner, every turn is potential for unused space and extra materials in my mind. The house on the left restricts interior wall placement due to exterior wall locations which, in the future would be more costly to alter. Whereas the home on the right is a long rectangle, the interior space is endlessly configurable to your needs. Keep it simple and maximize every last square foot of usable space.
Being in the renovation business we are constantly helping customers re-invent their living space. Let’s be clear though, some are easier to fix than others. If you design a space with the intention of altering it in the future those alterations will be much easier to achieve later down the road. When looking at the design it’s important to think about what fits your needs and what is going to fit your needs in 5 years, 10 years, or even 20 years. My co-worker Sophie has a great blog on the subject called What is a Flex Room? There are some great tips and examples listed there. Be sure to check it out.
Lastly, comfort is the most important aspect of any design. It all starts with a well-sealed envelope. This is achieved through several different systems working together. A thick wall of insulation, air/weather barriers, vapour barriers, and continuous insulations around the exterior of the entire home. These systems all work together to keep cold air out in the winter and hot air out in the summer.