Wood expands when it's humid because it absorbs moisture. It contracts when it's dry, because it loses that moisture. Movement from wood is 100% normal and to be expected seasonally. It perhaps may be magnfified in your case because the AC wasn't running when the work was done so there was more humidity around for the wood to absorb. Contact the contractor for a call back, but you have to be careful about making things too tight during the dry season. If you do that, you can get buckling and cupping when the humidity naturally rises come late spring into summer. You can also talk with a HVAC pro about installing a whole house humidifier. Most wood floor manufacturers and cabinet manufacturers require the home's humidity to be between 25-55% year round for their warranty to remain in force. That means using the AC in the summer as well, and being sure that it's not too oversized to handle the humidity.

it will cost less to use a dropped header.... Everyone has their opinions. THose that didn't do it, think it looks fine and isn't worth the money to flush it up. those of us who flushed it up think its worth it. I don't know exactly, how much mine cost, we are doing a whole house remodel. I had a cape style house and I flushed up/removed the entire load bearing interior wall that ran down teh middle of the house, it broke up what is now my kitchen into the dining room, and divided my living room in 2. I do know it took 4 pieces of steel and 6 microlams (2 peices of steel per side of the stairs, and 3 microlams per side) the steel total was $2500. I also had to add a steel support column in my basement on a footing. in my situation, I was removing bedrooms to open up the kitchen, and living room it was definately worth it. It made the renovation completely integrated and looks like a colonial not a renovated cape. you have to decide whether it looks natural where you have it, or unsightly.

Ditto to bluekit: Don't know how old your house is, but that also may complicate things. Based on our experience of the last week, we'd definitely pay the modest amount needed to get an engineer in. Don't trust a high school educated contractor to be able to calcuate the solution. Obviously very old houses are a real challenge. Ironically, I think that relatively new houses can also be a problem, as they are built in an era of "slap them up fast and cheap." You can't count on things being as they should be. That was the case with our 13 year old house. We are trying to move a short section of exterior wall out about four feet. Only after demo began did problems start to become obvious. First, the existing beam, built from three LVL's, is actually inadeqate. Second, the %^&*(% builder's electrician hogged out multiple 1-2'' holes at the end of the beam to run his wiring. This means that we can't just move the supporting column out to the end of the existing beam as we had hoped. So now we have not one but two engineers working on solutions. Currently it looks like we will need a roughly 24' steel beam running perpendicular to the existing beam. This in turn is too large to get into the house. Architect suggested having it welded on site. Contractor refuses saying fire hazard is way too high to allow this. He is hoping to be able to bolt two 12' beams together using gusset plates. Waiting for engineers to confirm bolting OK and (gulp) to estimate price. So...our advice. It may seem simple but you won't be sure til you open it up. I'd definitely have an engineer located and ready to take a look and confirm that your plans won't lead to all of the walls on the second floor cracking due to inadequte support. That may be the best $500 you'll spend on the renovation.

The hallway is 3.5ft wide. It's hard to say which walls are load bearing. The attic is completely open, no interior bracing. Joists run across the house (across the hallway) and from one side to the other is exterior wall, hallway wall (x2), exterior wall so the joists are only touching walls at 4 points. The hallway opening has a bigger 2x6 over it. I tried to draw a picture of how I think it's built. This part of the attic is hard to get to (air duct return, gas lines, etc all run right there). When I first bought the house I ran cat6 all over and I drilled through that double 2x4, I guess it's possible it's actually three 2x4s. You can only see the top one, but I had to have a drill bit extension to get through all the way. I think its cracking down that 2x4 "sandwich".