2x6 joist span for simple foot bridge

[Egon]

Culvert??

 

[Billrog]

If 2x6 is adequate for a 14' roof span why not a foot bridge ?

 

[ArlyA]

Rod, You on the right track and you have received some good answers. We build and repair bridges on a regular bases but receive snow here so we need to build them for that load. Do you there? Here is the latest one did this past summer that was just under 4ft wide to keep the atv's off it and 22ft long. Its stringers were three 4x12 unplanned treated lumber. All fasteners were structural screws or hot dipped bolts. Hope this give you some ideas.. This structure has no steps.

I'm making a simple foot bridge across a creek. It will not be for any machinery, ATVs etc - just people. The span between supports is just under 14 feet, the width will be 4 feet. I'd rather not use 2x8's or larger. If I space 2x6's 16" on center and use blocking to stiffen the joists do you think it will be sufficient? The bridge will not get heavy traffic and is out of sight of the public. I am not worried about strangers using it.

 

[Deere Dude]

I would not go less than what you would put in a house with that sort of span, and that seems to be 2x10s.

 

[LS Tractor Owner]

I have done a bridge similar to what you are doing. 2x6 are more than sufficient. I did double up the outside 2x6's on both sides, 2 singles on 12" centers in between. It's been spanning 16ft now for 15 yrs without any issues. Oh, I forgot that I did sandwich pressure treated ply in the 2 outer "beams". I'm no engineer, but worked in the housing industry for 20 yrs. lots of overkill there. I have a shed that has a 3/12 roof pitch, 2x6's 24" on center, spanning 16'. There is blocking at 6 and 12 feet. We have had some snows here totaling 36-40 inches, never had an issue. According to the span charts, it should have collapsed years ago.

 

[RobA]

Thanks for all the ideas and advice. I decided to go with 2x8s for the 14 foot span. I used 5 of them for the 4 foot width and it seems solid as a rock. Here's a picture of what I have completed so far:


The thumbnail looks like it's upside down but when I open it the photo is right side up. The boards off either end are for the approach ramps I am making rather than steps. They're not final and are just laying there for measurement etc.

 

[EddieWalker]

Are you making ramp to get on it? ADA says 1:12 pitch, and every ramp I've built, I've used that slope, and would go any steeper.

 

[RobA]

I am doing ramps. Thanks for that pitch info! I will definitely use that advice. (I edited my post to mention the ramps just as you were replying)

 

[Billrog]

Nice Bridge !!!

 

[Egon]

Looking good.