Rim joist
 

I ran into some rot issues on the front rim joist of my deck. The previous owner who installed the joist had butted two 2x8s together to creat the front joist. It spans 18 ft in total. My question is whether or not this is correct and should it in fact be one continuos board. Please help.

It's always stronger and better looking if you can use a full length peice but it is perty standard to have a joint in something that long.

As long as the joint occurrs where there is a deck post so that each end of the joist is attached/supported. Ideally, the joint should be a lap joint not a butt joint.

Ok thanks! I think I will go with a single board especially since there will be a railing attached. Will probably do some blocking where the 4x4 posts will be.

Yes solid blocking between joists inside where the post go.

Any chance of a picture of the area your working on?
The reason I ask is, I'm trying to see how long a span your trying to run, trying to see what may have caused the rot.
Good luck trying to find a 2 X 8 that long. They do make them but not something Lowes or HD will will have.

The rot i believe came from a terribly constructed Florida room that sat on top if it. Here are some pics. Found a 20ft piece this morning