I am reconstructing a 12x16 shed. The previous owner had used a ridge beam that was 2x6x16 feet long and the roof was sagging a bit. I was planning on replacing it with a 2x8 or a 2x10, but then I got to thinking...replacing the beam with something taller would require me to do a lot of cutting to "pre-fabbed" roof sections to make sure they fit correctly.

I now have the bright idea (or so I think) of sistering (2) 2x6x16's together. I am think this will give me the added strength I need to keep the roof from sagging. My internet research is telling me otherwise, as a couple of people claim that sistering does not add strength, just weight.

Any thoughts? Should I sister a couple of 2x6's together, or go the 2x8 or 2x10 approach?

Thanks in advance,
Bryan

 

A 2x6 won't span 16' no matter what, so I would go with a minimum of 2x8 doubled. Depending on how long your rafters are, you may be upgrading them, too.

 

Larry, what about collar ties? would that allow him to get by with smaller lumber?

 

Yeah, what about collar ties? The ridge beam should not have to support any weight.

 

You're both right, but if he is using 2x6 for rafters, it won't all bear on a lateral 2x6 fully. It will stick down below it. I should think he would want full bearing of the rafter, and thereby use 2x8 lumber to have the full surface bearing. I just lost my cursor . Collar ties would be a given.

 

I agree with Larry. The rafter ends would be cut at an angle. 2x8's would be a better choice for the ridge beam.