One collar tie would be enough in your case.
Shed roof ridge beam.
Look at it this way say 40 inch load at the ridge look at your 3 4 sheathed roof as a big 8 ft high 3 8 thick beam laid flat down to a 4 12 slope an eyeball number you better check shows that a less than 1000psi plywood would be sufficient with staggered middle edges and 2x6 rafters to keep em flat however you then have about 6000 pounds of lateral thrust at each end wall to deal with.
If you know the slope x in 12 you want to use for your roof framing design you can use it along with the run r to determine the height of the ridge beam.
The rafters are angle cut at the ridge end and notched with a birdsmouth where it meets the top plate of the supporting wall.
Here s a picture of a gable style shed using a ridge beam.
Determine your desired roof pitch.
Building trusses on site is easily done for a shed.
The difference between them is that a ridge beam is a structural member that bears half of the live and dead loads of the rafters on either side of it but a ridge board is not structural.
A ridge beam runs the length of the shed roof connecting every pair of rafters.
Now if you have done any looking around this site you ll quickly see that i am not a fan of using a ridge beam in shed construction.
You don t need a ridge beam but you do need a way to keep the walls from spreading.
However our instructions include making shed rafters with a ridge beam.
Determining the ridge beam height.
The term pitch refers to the slope of the roof.
Structural ridge beam tricks of the trade span for residential framing glulam ridge beam span table elcho beams tables golagoon nz glulam beam span tables designing with roof rafter span tables.
In order to adhere to standardized building codes and ensure adequate runoff your shed s roof must have a pitch of at least 3 12 read as three in twelve.
Yes either a ridge board or a ridge beam is necessary and required by the building code where roof rafters meet at the the center of their span.
Lawriter oac 4101 8 01 roof ceiling construction.
Versa lam lvl size chart laminated beam span tables charts.
A simple gable shed roof is often built using 2 4 or 2 6 lumber for the rafters and 2 4 for the collar ties.
For example if the slope is 4 in 12 and the run is 12 feet the ridge beam height m will be 4 feet.
I always always build trusses.
A proper beam would have a supporting post at each end.
Shedme shed roof rafter span.