determining beam size

[John (archive)]

Hey everyone,

I'm pushing my carpentry skills a little by building a small porch onto a corner of my house.

I'm in the planning stage right now, and I'm trying to determine beam size. My porch will be 8 feet deep, but 16 feet wide. I was hoping to get a beam for the front 16 foot wide end of the roof that can be held up by just 2 posts, one in each corner. I've got a few tables from a deck building book that does not have anything to span 16 feet.

I've talked to a couple of builders, and they tell me they just ask the folks at the lumber yard. I'm looking to find a chart that will help me determine for myself.

any suggestions?

-Thanks,

jeff

 

[Doug Miller]

I've talked to a couple of builders, and they tell me they just ask the folks at the lumber yard. I'm looking to find a chart that will help me determine for myself.

any suggestions?

Visit your local library and look for texts on mechanical engineering. "Simplified Design of Structural Wood" and "Simplified Mechanics and Strength of Materials," both by Harry Parker, are particularly comprehensive _and_ comprehensible.