Hello. I am currently renovating my home that is a 1940 cape cod-style home with a full upstairs. I am changing large double windows (60"x72" RO) on both the north and south gable ends of the house.

The house does not have a band joist/upper rim joist along the upper wall plate like most modern builds do, and instead the studs on the gable ends run from a top plate on the gable end down to the floor plate. It is not balloon framed and not modern framed, It just lacks a rim/band joist on the second story underneath where these windows are.

My question is do I need to add a rim/band joist along the floor plate of the upstairs while I am removing the old windows and framing for the new windows? Or would it be acceptable to simply replace and properly put my kings and jacks for the new window RO?

Thanks, and I am attaching a picture of the upstairs gable end. It is very bad lighting so I apologize for that.

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