Channel One wrote in post #16160783I would consider 12 to be a minimum for a studio but the maximum practical for home, you want a studio but it should be built to add value to your home as well.
That is a very good point for designing something used for home business: "What can this space be used as by someone else when the property is sold"
Talk to your designer about alternative space usage, and probable changes to door/window placement. Depending on the style of the exterior, layout of the space, and layout of the property, then framing suitable headers ahead of time can be a nice 'check box' a realtor can use to move your property. This can so so far as to adding footings for a fireplace. "We have the ground work for all these features to be put in as an easy renovation. This makes them an easy job with minimal work, whereas without them it would be far more costly and time consuming to put in place."
I've seen someone who went so far as to design a home business extension to his house as two stories, but in such as way as to allow the second story floor to be constructed after the fact. (Even wired all the 'rooms' on the second story with electrical outlets and empty lighting boxes.) While only needing about half again as much head room for the lift he was using, designing it that way meant he added a pair of bedrooms onto the house in a weekend when it came time to sell.
Not saying everyone should follow that route, but planning things like a 'storage loft' above a 'family room' can easily give you a good excuse to stretch ceilings well beyond 'normal' with a positive impact on resale value.
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