L shaped building/gable roof

I have been told that a home that is L shaped is much more expensive to build than if the extra space was just included in primary rectangle–no”L” The reason I was given is that the cost of joining the roofs is too expensive. Can someone give me an example of what the additional percentage might be? Thank you
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Replies
Anne,
It really isn't possible to come up with the percentage you seek, because the upcharge for a complicated shape depends on the specific characteristics of your lot, the shape of the building you are considering, and your local labor rates. Suffice it to say that the upcharge doesn't just come from "joining the roofs." Everything costs more for an L-shaped building than a rectangular building -- from the foundation to the wall framing to the roof trusses to the roof flashing.
Here's something to ponder -- a fact that is more important than the initial cost of construction: a rectangular building without bump-outs will cost less to heat and cool than an L-shaped building, and is therefore more green. For more information, see Green Building for Beginners.
Anne,
For the benefits of a bit more articulated house shape, see the "A house for Slow living" Blog on the GBA front page.