Rafter Ties on Hip Roof?
Rafter Ties on Hip Roof?
(OP)
I'm planning a pavilion structure, 28 x 24 with a hip roof supported by doubled 2x10 wall plates. The plates are bolted in to rabbet atop 6x6 posts set in concrete. No walls, no ceiling. Will I need to add some type of rafter tie and if so, how?
Thanx,
Jim
Thanx,
Jim






RE: Rafter Ties on Hip Roof?
A hipped roof can be designed without rafter ties or internal columns by using the wall plates as tension members and the roof deck for stability. Without roof deck, the four hip members together with a four foot long ridge beam form an unstable structure when hinged at all six nodes.
If there was no ridge beam, the four hip beams would meet at a point and would form a stable structure if hinged at all five nodes.
BA
RE: Rafter Ties on Hip Roof?
RE: Rafter Ties on Hip Roof?
Thanx,
Jim
RE: Rafter Ties on Hip Roof?
Another option is to use a truss at each end of the ridge beam designed to support a concentrated load at midspan from the hip beams and ridge beam. Then you do not need rafter ties.
BA
RE: Rafter Ties on Hip Roof?
Jim
RE: Rafter Ties on Hip Roof?
BA
RE: Rafter Ties on Hip Roof?
Mike McCann
MMC Engineering
RE: Rafter Ties on Hip Roof?
Then you have not rafter ties.
RE: Rafter Ties on Hip Roof?
Jim
RE: Rafter Ties on Hip Roof?
BA
RE: Rafter Ties on Hip Roof?
BA
RE: Rafter Ties on Hip Roof?
RE: Rafter Ties on Hip Roof?
RE: Rafter Ties on Hip Roof?
Personally, if I wanted to stick frame a hip roof, I would use the wall plate as a tension tie and the roof deck for structural stability as mentioned in my first post. I might use some temporary rafter ties or interior posts during construction but would remove them upon completion.
That seems to me to be the most practical and satisfactory solution but it does require special attention to the connection of the hip beam to wall plate at the four corners of the building. Also, the wall plates would need to be spliced adequately to carry the calculated tension.
BA