* Existing deck sits at 3 ft off grade
* New master bedroom patio doors are at 5.5 ft off grade — so I need to bridge a 2.5 ft height difference
* Plan is a two-tier deck: lower tier ties into/extends the existing 3 ft deck, upper tier lands at the 5.5 ft patio door threshold

**Issues I'm trying to solve and would love opinions on:**

1. **Basement window well / egress** — There's a basement window (egress) in the footprint of where the upper tier needs to land. Need the structure to clear it without blocking emergency egress or creating a water-trap around the window well. Thinking about framing around it with a clear opening rather than building over it, but curious how others have handled this exact conflict.
2. **Cantilever vs. freestanding posts** — My first instinct was a cantilevered ledger board off the house to support the upper tier, but I'd rather avoid attaching a structural ledger at that height/load and deal with the flashing/water intrusion risk long-term. Leaning toward a fully freestanding post-and-beam structure instead, independent of the house wall. Anyone done this for a similar elevation change? Pros/cons of going freestanding at this height vs. a properly flashed ledger?
3. **Mechanical vents** — There are vent terminations (dryer/bath fan, possibly furnace intake/exhaust) on this wall too, and I want to make sure the new upper tier doesn't choke clearance to any of them once decking/skirting goes up.
4. Hot tub will be moved and won't be placed on new deck. 

Planning to do this myself (have done a fair amount of structural work before) but want to pressure-test the approach before I start digging footings. 

Located in Alberta if that affects code answers (footing depth/frost line, electrical clearance rules, etc.)

Two-tier deck extension to reach upper patio doors