A question came up on the correct size that an rafter collar tie should be and how many should be used. Does any body know the correct answer for this? I see mostly 2x4’s. If you can help please let me know, and what your source is.
Thanks
Rick
Too many variables to answer your question properly, please re-phrase and explain the condition , and pictures would help.
Marcel 
Richard,
Most jurisdictions have only one regulation for collar ties, and that regulation is: They must be at least one inch thick. Some have two regulations, they must be at least one inch thick and placed at least every four foot.
How’s that. 
Not much was it.
John;
Every little bit helps, right?
I would prefer something of the 1 1/2" thickness to match the pitch of the roof action.
Since I don’t know the pitch of the roof, I guess one could say that the 1" would be inadequate.
Marcel 
Most of the collar ties I have seen are at least 1" think and spaced on every third rafter. I have seen all kinds of material used to comprise collar ties including left over floor boards, 2 x 4’s, 2x8’s, and furring strips.
They come in all shapes and sizes. I recommended upsizing the furring strips as they were not doing the job (mostly split and rafters were beginning to seperate from the ridge board.)
Don’t forget the good ole mighty cable. It’s sometimes fun living in cow country. I’ll still never forget the house that was plumbed by an ole time farmer. Must have been at least 200 feet of garden hose used.
John,
That farmer moved out here…
Many builders will think one inch thick includes a 1x6 and it does not.
A 2x6 is the minimum any one should consider.
Even if some code allows a 2x4 it is just plain wrong unless the length of it is less than 3 feet.
Bruce,
1x’s are fine…
Here in Canada, the minimum size is 1x4, and they must be placed at all jack rafters that exceed the span requirements, after all, they are not only used for strength, but to reduce the span. Also in Canada, there is a code for the amount of nails used in collar ties.
Richard,
You should post this in the structural section. There are some some sharp structual engineers that will likely reply to your post. They may not be monitoring the interior section.
Does eveyone know the difference between a rafter tie and a collar tie? A rafter tie is placed in the lower third of the roof framing to prevent rafter/wall spreading. A collar tie is placed in the upper third of the roof framing and holds the rafter down to the ridge.
Thanks to all. It is just what I thought, there is no right answer. All different sizes are used. I may look up the local code and let all know.
Regards