If you are thinking about replacing old rotted porch posts the first thing you ll need to know is how to jack up and support the roof structure properly and.
Roof corner support.
Drill holes in angle iron to keep the rafter from buckling again you will need to secure it with a piece of 1 2 inch angle iron.
If the post is not going to be perfectly level use a pry bar on one corner and shim the post before you secure it into position.
In this situation the walls of a finished attic space or room would go with the roof line.
Extra support for the trusses can be made by placing a 2 by 4 inch piece of lumber from each truss on one side to the truss on the other side high enough to provide head room but low enough to provide support for the trusses.
This article describes and illustrates the different types of support that prevents roof sagging and wall bulging at buildings including definitions of collar ties rafter ties and structural ridge beams.
This will give some added strength and take care of any cracks in the wood itself.
Collar ties rafter ties tension beams structural ridge beams.
Some of these can support the roof and prevent ridge sagging and wall spreading.
Each side of the iron should be four inches wide with the entire piece being at least two feet long.