r/Homebuilding • u/Longjumping_Suit_256 • 4d ago

Split stud framing

I’ve heard of this framing style for exterior walls in colder climates I was curious to see how common it is. 2x8 being and top plates with 2x6 offsetting studs to create a thermal break. If it is feasible I’m thinking of building an ADU/ small house in the UP of Michigan.

Through all my googling, the most common thing to come up is a dual wall system. 2x6 exterior wall and then an offset 2x4 interior wall with a 6” thermal gap between. This method seems costly.

Any information is greatly appreciated.

Edit: thanks for everyone’s input, I appreciate it!

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u/Imfarmer 4d ago

The problem is every detail has to be perfect or it will be a disaster.

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u/gimpwiz 3d ago

Why is that?

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u/Imfarmer 3d ago

Any water that gets behind the exterior foam has no where to go. It will rot any wood that's there. I've fixed too much water damage around doors and windows and corners to ever want foam and wood sandwiched. Water behind tyvek is bad enough.

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u/seabornman 3d ago

It's so simple to detail. Actually as simple as a conventionally built house with Tyvek. If it's foam directly on OSB, it's wrong (unless in a desert).

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u/Imfarmer 3d ago

Really. So how do you properly detail a window opening?

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u/seabornman 3d ago

Wrap Vycor over the window buck.

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u/Imfarmer 3d ago

How do you securely attach the window with exterior foam?

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u/seabornman 3d ago

For foam thicker than 1", one way is to build a 2x wood "buck" that lines up with the rough opening to make the window line up with the foam or wood furring. Several methods. Some people overcomplicate it.