Running wire through sole plate and joist at an angle

OK, lets start by correcting some terms. The structural members you want to raise are not rafters, they are ceiling joists. You are right that because you have balloon framed walls, that has no effect on the top layer of ceiling joists. Changing these joists have no effect on the balloon framed walls. The thing you have to determine is if the ceiling joists are tied to a load bearing partition somewhere near the center of the house. If you have full roof rafters with a ridge board, it is very unlikely that the ceiling joists are tied into any down supporting bearing wall. Raising them should not be a problem if you plan for support of these joists if there is any center resting point, via a knee wall on the center resting support. If these joists span the entire width of the structure, then you can safely shorten them and reconnect them to the roof rafters. They serve two purposes. First a ceiling joist, and second, a collar tie for the roof rafter. I think you will be fine, however, I'd love to see some pics of the attic area with the joists. Good luck.

My answer is to cut your two inch hole as close to your drywall as possible. In the picture you went right down the middle and barely hit the joist. Methinks that you could drill right along the side and have to barely notch out the joist below. Might not even have to notch all the way through it. No reason for vac lines to have to be centered in your wall. Use the notch guidelines I found to help further.

• Notches in floor joists may occur in the top or bottom of the member but may not be located in the middle third of the span.
• A notch may not exceed one-sixth of the depth of the joist except at the very end where it may be one-fourth of the joist depth.
• The length of joist notches cannot exceed one-third of the depth of the member.
• Holes bored in joists must not be larger than one-third the depth of the joists.
• Holes cannot be located within two inches of the top or bottom edge of the member, or to any other hole located in the member.
• Holes cannot be located within 2" of any notch.

Below is a helpful chart that provides actual notch and hole size limitations for 2x4, 2x6, 2x8, 2x10 and 2x12 joists. It should be noted that limitations on the allowable notching and boring of wood joist are meant to retain the structural and functional integrity of the member.