Header size help

[svtlightning]

I am wanting to cover a 12' by 18' patio with a gable style roof with 4/12 pitch. I have 3 brick pillars located 12' from the house, spaced uniformly along the 18' lenght. I will attach the ledger board to the house. My question is what size header(?) do I need to span the 12' from the house to the 3 pillars. I am in the St.Louis area.

thanks
Mike

[Rich]

For a glulam you're looking at 3-1/8"x10-1/2" architectural grade glulam. Or 5-1/2"x9". Just depends on the look you want. That's with a snow load.

[svtlightning]

Thanks Rich.
Is there any combination of dimension that I might be able to use.
As far as looks, I was thinking of covering the ceiling of the patio.
Were you speaking of exposed rafter?
Mike

[Rich]

If you have the trusses / rafters sitting on the beam it will be exposed. The ceiling would be covered at the truss line.
Don't understand the combination of dimensions question>>

[svtlightning]

Oops, I meant to say Dimensional lumber.

[Rich]

Looking at a roof live load of 30psf - and spanning 12' you're looking at 4-2x12's or for 20psf live load your looking at 3-2x12's.