Timbertech 45 degree miter joints - use sipo dominoes?

[kfitzsimons]

I'm just about to begin rebuilding my deck with Timbertech Earthwood Evolutions Legacy. I'm doing a "picture frame" edge which means 90 degree corners cut on a 45 degree angle. Timbertech recommends about a 1/8" gap in the joint to allow material movement. Has anyone used loose tenon sipo dominoes for that joint?
Thanks, Kevin

 

[copcarcollector]

I saw this exact thing on This Old House recently, they were building a staircase that had a 45 degree joint using Ipe decking. They used Dominos in the joint, I dont recall what they did for a gap, if anything. Looked great when finished.

Pretty sure it was episode 3412, #4 of 15 at the Lexington Colonial House project. I can find other episodes on that house, but I cant seem to find this specific one.