I did find this post that shows installation of a portico on an already sided house that shows how they cut away the siding for the roof structure.
Portico roof drainage.
The most critical of these issues is the flat roof drainage systems.
Along with the benefits of a flat roof come unique challenges.
Flat roof drainage system specifications designs troubleshooting problems solutions for interior drains on flat building roofs flat roof drains scuppers and screens questions answers about keeping the flat roof drainage system working or about installing new drains in a flat roof.
These ditches guide water toward the eavestroughs.
Here is a diy under deck roof and drainage system part 1 i m here with my parents to show you how to install a diy under deck roof and drainage system part 1.
Adding a roof can create drainage problems if the roof pitch is too shallow.
Your building and location can help determine which drain will fit your roof needs.
Minimum roof pitch the minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
Drainage ditches are created in the roof in the lower insulated areas.