Watershed.

When you build, you have to consider water.

Water. Falling, flowing.

Once you consider that, you have to then consider water.

Have I mentioned water?

So the '33 addition was built without an adequate overhang. As such, the water runs right off the roof, down the wall, and onto the foundation.

The '98 roof is lower that the '33 roof in terms of watershed. In actual terms, the peak of the '98 roof goes over the '33 roof.

Both of these issues, are bad.

Starting with the '98 roof, it shouldn't go over the '33, not without completely redoing the '33 so that it is seamless with the '98. Instead they just flattened the ridges and laid the new roof on top...flashing it of course. To be fair it seems to work, but we'll fix it when we redo it in a few years.

Except for along the wall where they didn't flash, and without an overhang the water just flows down the wall. It also soaks the foundation...