Hammerbeam truss
A short beam thrown from the wall carries the roof, no tie across the room.
The hammerbeam throws a short beam out from the wall, braces up to a strut, and carries the roof without a tie beam crossing the room. It's the one that makes great halls feel great.
How it works
hammerbeam short beam, cantilevered off the wall brace transfers the thrust down to the post wall post takes the outward push, buttressed below span 30+ ft with a fully open ceiling
When to use it
Halls, lofts, and anywhere the ceiling should be the star. It's the most theatrical frame — and the fussiest to cut true.