How many corners in a green house?
Hi All,
Making some prelimary plans for a new custom house near Green Bay WI (climate zone 6).
My family would like to incorporate a large front and rear porch and a side entrance garage. Many of the house plans I like (country style) feature gable roofs with dormers have several bumped out areas or have gable endwalls that narrow up to a smaller gable endwall. The end result is a lot of corners. Some of the houses that look the nicest IMHO have up to 16 inside/outside corners!
Besides adding expense to the house, how bad of an energy penalty are these corners when using either thick exterior foam or double stud wall construction?
Any architectural “tricks” that can be used to add visual dimension to a house at a lower energy penalty?
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Replies
The Manual J doesn't impose a penalty per se for corners. However, what corners tend to mean is that the wall area is greater for the same square footage. If you limit yourself to straight walls, a square is the shape with the most area relative to the circumference; the more you deviate from a square the lower the ratio becomes. Wall area is what drives heat loss.
Now, in a modern house the heat loss through the walls is pretty nominal. Most of the loss is through the windows and doors, and particularly skylights. The advice I would give is to get someone who knows what he's doing working on the Manual J, and integrate the Manual J into the design early on. Then set a "budget" for where you want the efficiency to come out, and start playing with different alternatives.