I inspected a 15 year old house with a hip roof. The attic had collar ties present beneath the ridge which spanned about 15 to 20 long. There were two vertical 2x4 supports about 16feet long that were on either side of the ridge (one side attached to the ridge and the other side to the attic floor). These two supports were either bowed or twisting. Is this something to worry about? Or do the collar ties offer enough support. The ridge showed no signs of sagging.
A picture would help, however, depending on the rafter sizes, or the span of the rafters, collar ties may just be an added bonus.
a 16 foot 2x4 will twist no matter what you do with it, unless you use on top or bottom of a stud wall as it was designed. twisting doesn’t effect it’s vertical stregnth so much, but with any kind of load that long bugger will split and fail. i’ve always though that if you need something that long for vert. support, you better use a 2x6, or 2 2x4’s nailed together with the crowns going oposite ways to counter the twist.