I am looking to add a 2 story addition coming off of the left side of my house which will be 20x24. The 1st story will be partially below grade and tie-in to my existing walk-out basement which is step-framed with 2x6 platform framing. The 2nd story will be 14' walls to create cathedral ceilings and will tie-in to my existing 1st and partially 2nd floor wall which is balloon framed. Being new to building an addition I have some questions that I'd like to get answered before I start drawing up plans. 1. Will this new addition need to have 4 freestanding walls or will I just need 3 walls and the 4th wall would be the existing exterior wall of my house? 2. If I only need 3 walls for the addition, how will I tie in the new roof and walls to the balloon framed walls on the existing 1st and 2nd floors? 3. I am assuming I will also need to tie the foundation of the existing house to the foundation of the addition as well. (I think this is called pinning) If that's the case then I must need to build 4 free standing walls? Before anyone mentions it I am planning to get a structural engineer involved I just want to have a general idea of what I should be asking for and what is possible. I'd also like to draw up the plans myself first to save a bit of money on that yend and then just have them reviewed by a professional. I'm not entirely new to framing as I've remodeled a basement, built a 32'x12' deck and a large shed but this would by far be the largest thing I've taken on Thanks!

I'm in the process of installing furring strips + sheetrock on the inside of my exterior walls, and I'm also now planning on replacing my front door. In the process of removing the front door molding I found out the corner wall of my house has seperated a 1/2" along the frame of the front door. At first I was very concerned, but after further investigation I'm not sure if it's actively separating, or if it's settled this was years ago. [B]1st picture[/B]: The exterior walls are structural clay tile with a brick facade on the first floor, and stucco covering the second floor. I've known there was some issue from the exterior of the house, but never realized the seriousness of it until the molding/interior plaster. For years the front has looked like the first picture, clearly there was separation at the top. But it hasn't visibly gotten any worse. And the crack stops behind the aluminum trim. It does not continue up corner through the clay tiles/stucco on the 2nd floor of the house. There is an a small "sun room" attached to the house/wall that's visible in the picture. [B]2nd picture[/B]: After removing the interior molding on the door, some of the plaster came down with it. I saw that existing "header" was an old style 2x4 underneath the structural clay tile. And you can see in the picture, the corner has separated enough that it appears the header is barely holding/overlapping the concrete support on the right side. Outside, underneath the brick facade on is a steel plate holding up the bricks across the top of the door. (Visible in the last picture). [B]3rd and 4th pictures[/B]: Just to make things easier to see, I outlined some of the wood in the picture in red, and concrete the installers used in blue. Like I said, I was less concerned after further investigation, both the wood header and also the other red-outlined wood "support" on the right, do not appear to be carrying any weight. As you can see in the 4th picture, the header slides out without any effort, the same goes for the 1x4 on right. I'm hoping that means the structural clay tile is still doing it's job well, and if I can remove just the header and replace it with a longer steel plate to provide more support than it currently provides? I'd also fill the gap beneath the 1x4 with concrete. [B]5th picture[/B]: I'm planning on getting a new pre-hung exterior door, hopefully that I can secure into the walls better than the current (original) door has been all these years. Basically it was secured to the moulding. :( But I'm wondering how can I prevent further separation? I know waterproofing the outside is key. I should also mention the (again, larger, old-style) 2x8 joists in the ceiling run in the same direction as the header (across the door) and there is one almost embedded in the clay tile right above the door. My point being they should be helping hold that wall. Thanks Edit: I didn't know exactly which forum this belonged in, I assumed it was a more a structural framing issue, than exterior brick?