Many sags and droops may need to be addressed and straightened in your barn.  Below are some pictures that should give you a general idea of the re-roofing process.

Here we are tearing off asphalt and shake shingles.  This is an extremely important step in re-roofing your barn.  Never let some one suggest you simply apply knew shingles over the old ones!

After the tear off your roof may need additional purlins to address any sagging.  Here you can see the horizontal pine 2X4s we have added to make sure the barn roof is straight.

Rotted soffit being rebuilt.

View of soffit work.

The roof nearing its finish!

The North side of the barn with a finished metal roof and metal siding.