I have tried to build stone roofed houses on multiple different maps, but my workers always stop building the house when they get to the last wall before the stone roof. They are not getting trapped or anything like that. I have the materials available in my stockyards, and plenty of them. So I’m thinking this must be some sort of bug like error. The workers just become idle as if they do not have a job to do.
Here’s my save file:
I think (at least for the game shown above) it’s the berry bushes next to your scaffolding. I remember having a similar issue in one of my past games. There’s also some issues with stone as a resource still that might be contributing, especially the farther you get into a game.
Illegal construction. I.e. your house is bugged. Note the red floor plan.
House construction rules I stick to:
-Save before your start any new construction.
-4 squares away from any terrain feature, house, bushes, plants, zones, farms/garden. That’s 4 squares from the wall, not the floor plan (so 5 squares away from your floor plan).
-Don’t craft the doors and windows. Let the building fully finish and then as the roof is completed, have your carpenter craft the windows and then the doors.
-Leave lights, furniture, and beds to the very end when the house is fully completed.
Red floor plan means your house is bugged, ergo your game is now bugged. You will have to start anew or revert to an older save 
Some other notes:
-Don’t put crafting stations (Weaver’s loom, or carpenter’s bench) inside Buildings. By buildings I also mean any roads, patios, or decks you build using slabs or flooring. Although it may work at first, eventually you’ll have rogue path finding errors and the associated villager (carpenter or weaver) will become stuck permanently. Devs need to look at this. Note; sometimes the villager won’t get stuck, but some of the things they make will get stuck in the walls or on the floor of the building. Especially if you have them craft something without a designation (such as fence parts).
-Don’t build patios and decks. Until path finding is further fleshed out, these will count as extra Buildings and will cause all sorts of path finding errors. Dev needs to allow us to create patios, decks, roads, and pavement that isn’t declared a “Building”.
