steel beam length

otto man · 07-25-2008, 03:02 AM

I am trying to figure out what the smallest steel beam possible is to span 28' while supporting a deck with a dead load of 300 lbs and live load of 1200 lbs. The deck will be supported at one end by this beam and at the other end by a wall to my house which is quite sturdy. The decking will be redwood 2x6s that extend from the house to the beam. Is a W8x10 too small? It's a long span, but the steel beam won't be expected to support much weight. Is there such a thing as a W10x10? I'm just looking for a ball park estimate. Nobody at the place where I buy my steel speaks english very well so I can't get even a rough guess.

**Termite** · 07-25-2008, 08:39 AM

I'd strongly suggest contacting a structural engineer for this task.

concretemasonry · 07-25-2008, 09:02 AM

Your load looks low, but you did not provide enough details like deck size and location. Is that total loads or per foot loads?

Strength is one thing. At 30' long, you will probably have more problems with deflection and a springy deck.

Not for an amateur to design.

Dick

billie_t · 07-27-2008, 12:28 AM

you do need an engineer but a ball park figure for what you are thinking of is half your span in feet.... in inches of beam....this is no formula for substituting an engineers stamp but i think it will be close to a 14 inch beam of medium weight

28 feet devided by 2 = 14 feet = 14 inch beam

**AtlanticWBConst.** · 07-27-2008, 09:11 AM

Try another supplier. Most have a service to provide you with the calculated beam dimensions, and engineer-stamped specs, which may be required in order to get, and approve, a permit and inspection.

07-25-2008, 03:02 AM	#1
otto man Newbie Join Date: Jul 2008 Posts: 1	steel beam length I am trying to figure out what the smallest steel beam possible is to span 28' while supporting a deck with a dead load of 300 lbs and live load of 1200 lbs. The deck will be supported at one end by this beam and at the other end by a wall to my house which is quite sturdy. The decking will be redwood 2x6s that extend from the house to the beam. Is a W8x10 too small? It's a long span, but the steel beam won't be expected to support much weight. Is there such a thing as a W10x10? I'm just looking for a ball park estimate. Nobody at the place where I buy my steel speaks english very well so I can't get even a rough guess.

07-25-2008, 08:39 AM	#2
Termite Moderator Join Date: Apr 2008 Posts: 6,520	steel beam length I'd strongly suggest contacting a structural engineer for this task.

07-25-2008, 09:02 AM	#3
concretemasonry Member Join Date: Oct 2006 Location: Minneapolis/St. Paul, Minnesota - Latitude 45.057 Longitude -93.074 Posts: 3,357	steel beam length Your load looks low, but you did not provide enough details like deck size and location. Is that total loads or per foot loads? Strength is one thing. At 30' long, you will probably have more problems with deflection and a springy deck. Not for an amateur to design. Dick

07-27-2008, 12:28 AM	#4
billie_t Member Join Date: Feb 2008 Posts: 51	steel beam length you do need an engineer but a ball park figure for what you are thinking of is half your span in feet.... in inches of beam....this is no formula for substituting an engineers stamp but i think it will be close to a 14 inch beam of medium weight 28 feet devided by 2 = 14 feet = 14 inch beam

07-27-2008, 09:11 AM	#5
AtlanticWBConst. Lic. Builder/GC/Remodeler Join Date: May 2006 Location: New England Posts: 7,554	steel beam length Try another supplier. Most have a service to provide you with the calculated beam dimensions, and engineer-stamped specs, which may be required in order to get, and approve, a permit and inspection. __________________ - Build Well -

steel beam length