energy: I wondered about the air seepage aspect. What is "taped and floated" sheetrock? where sheetrock walls meet sheetrock ceilings, rather than covering the gap with molding, the wall rock & the ceiling rock has sheetrock tape installed and sealed to wall & ceiling rock. this eliminates the gap so that attic air stays in attic. same method used when moldings are not being installed at ceiling. then if you add moldings...you are good to go because the air leakage site is sealed. if moldings are already installed, then you caulk top of molding to ceiling, bottom of moldings to wall and caulk any cuts and corners. seal air tight. The sheetrock is cut off at the bottom, so it's not hitting the floor, and it was taped at seams... do you mean something beyond this? I was referring more to the ceiling moldings, but the sole plate of the wall at the floor should have been sealed with seal sill or caulked when walls were stood up. this sole plate leakage is like the ceiling sealing a leakage around the total wall area of outside walls. Is the possibility of mold is as much a concern in a northern climate as in a southern climate (I'm in northern-most NYS, on the Canadian border)? Of course, we do get some hot, humid days in summer. I'm a hot humid climate gal, so cold is not my area of expertise. but air leakage is air leakage. most heating escapes through ceilings. sealing at the moldings ( or behind... taped & floated sheetrock) is good inexpensive long term savings. all penetrations through ceilings into attic should be sealed. cuts in ceiling sheetrock for hvac supply boxes, cuts for recessed lights and any penetration from attic into conditioned space. best of luck

I put the shoe rack that came with the dryer into the laundry tub to keep stuff from blocking the drain. Haven't had an overflow since. BTW, we have a floor drain, but it didn't end up at the low point in the floor.

I installed the baseboard myself, so I know there are ~1" gaps between floor and drywall. I'm worried this is where a lot of the smoke is coming in. There are definitely some gaps between wall and trim as it's an older house with pretty wavy drywall. I'm also thinking about sealing between floor and trim on the rooms with vinyl planks. Open to all suggestions!

Some pictures of the areas you're working on would be helpful. If the caulk is peeling off, I would assume you also have peeling paint? Or is your trim stained and clear coated? I would not discourage you from caulking everything, but it is usually not the first step of the process. My husband and & I are NEARING the completion of a 6K remodel. I have caulked all the trim (base, casing, crown, chair rail - hundreds of feet)! Ours is painted. I wouldn't use anything made by DAP, or any other brand you can buy at a big box store. My favorite caulk is PPG Top Gun 400. I buy it by the case. Last fall, it was still about $4 per 10 oz tube; comes in white or clear. Google for a PPG dealer near you. Usually more of a warehouse type place for painting contractors, but they also sell to the public. A larger gun will be awkward to use inside. The large guns & tubes of caulk are meant for exterior projects. Why are you using SO much caulk? Does some of your trim need to be re-attached? Are the walls out of square in places? Oversized gaps need to be filled with backer rod before caulking. One other thing - is your trim moving due to temperature and humidity swings in the house?