Generate navmesh at runtime?

In my game buildings are built by the players and AI (at anywhere on the map) during gameplay.

I’m currently using a lot of hacks and traces to allow the AI to navigate.

I’m curious if it’s possible to utilize the UDK navmesh system, but do it at runtime. I know it’s possible to add obstacles to existing navmeshes at runtime, but is it possible to generate a navmesh from scratch during gameplay?

pretty sure it’s not possible