Pitched roof into flat/shed roof over a porch.


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I've attached a picture of the actual house and what I am trying ot do. I need to duplicate the existing roof and then extend out flat roof on the right and left sides. 

I have created three spaces but cant get them to line up. I've used room dividers but that doesn't help. I also need to keep the upper siding but changing to invisible walls eliminates it. Help!

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For a weatherproof transition between these roof types, implement these critical steps:

Structural Connection:

  • Install double 2x ledger board on main house with 1/2" galvanized through-bolts (spaced 16" OC)
  • Use Simpson H1 hurricane ties at rafter connections

Water Management:

  • Step flashing must extend 12" up pitched roof under shingles
  • Saddle flashing over flat roof membrane (minimum 24-gauge galvanized)
  • Slope flat roof 1/4" per foot toward scupper drain

Material Transitions:

  • Ice/water shield over entire flat roof deck + 3' up pitched roof
  • EPDM or TPO membrane for flat section with termination bar at pitch transition

Climate Consideration: In freeze-thaw regions, add heating cable in gutter above transition to prevent ice dam formation.

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