Follow up to beam question

[rakuz66]

Just thinking about this beam again.  I have heard of flitch plates where you sandwich a steel plate between 2 2x10's, etc, but has anyone ever heard of lagging a steel plate to the bottom of a beam?? In other words the steel plate would be laying flat(horizontal) to the bottom of the beam, rather that (vertical) in between.  I realize that vertical is stronger, but at this point it would be easier for me to lay it flat against the bottom of the beam rather than taking it all apart, if I decide to do it.. Any thoughts welcomed.

[John Raabe]

It would increase the resistance to bending or sagging by the addition of the high tensile strength of the plate. I would think the total area of the connectors (nails, screws, lags) would be the determining factor in strength. More area here would be better.

[MountainDon]

Do the joists sit on top of the beam or are they butted up to the vertical face of the beam using hangers? IF the joists are on top of the beam, you could affix two sections of heavy steel right angle stock to each bottom edge. Steel comes in 20 ft sections. Some sources will cut and sell less. These could be drilled and through bolted horizontally through the beam.

As an alternate you could use rectangular steel tube, say a 2" x 6", laid flat against the beam bottom. The steel box shape has much more bending resistance than flat steel plate. That way you'd have both the resistance to bending and the tensile resistance to strengthen the wood beam.

A third method would be a length of steel channel, placed like a U, under and around the beams sides.

[rakuz66]

Thanks Mtn Don! the ceiling joists and rafters sit on top of the beam.  I kinda like the idea of a U shaped steel plate.  I think I would feel comfortable wrapping this around just 1 of the beams and then I plan on placing big posts, underneath both beams to hold it all up.  Remember there are 2 seperate beams( double 2x10's) 2 inches apart.  Or would you think i big U plate covering both???  Or 2 seperate U plates??

The reason I am overly concerned is this:  Do you recall seeing CNN cover all the Lake Effect snow off of Lake Ontario last year, where NY got over 120 inches in 2 weeks??  Well, that's where this camp is located.  However, I did not own it then and it withstood all that with cut trusses and a 2x6 beam before I started rebuilding it. 

Now, onto this beam.  If I go U shaped steel, my take would be not to even bolt it to the beam, just wrap it around it and support it from underneath???

[MountainDon]

I couldn't/didn't remember the specifics. 

Depends on the type/shape/size of steel you can get. If possible to place under/around all the beams that would give maximum strength. But around just one would likely be as good. If you're placing supports under the beam You may not need to go to the bother and expense of the big steel. The main thing then would be to have adequate footings for the posts. If there's a concrete floor/pad under the beam you'd have to cut through and excavate down to be certain. Place a concrete footing under frost line, etc...

I'd secure it in place even if I had posts under it, just to ensure it didn't fall if for some reason someone removed the posts for some reason. But that's just the cautious side of me speaking.

[rakuz66]

Having adequate support at both ends with solid footers seems to be the consensus.  Are steel plates expensive??

[MountainDon]

Expensive? Relative to what?    Depends.

Checl your local yellow pages for a steel supplier. Where I am there are about three suppliers on new steel, one priced much better than everyone else. But only if you buy full 20 ft sections or half sections.

There are also a couple of used steel dealers, but you are limited to what's on hand.

I check around and see what makes sense to you.

One question would be how heavy a steel is needed. I don't have a ny strength tables for steel. Maybe Glenn will have some idea?

[rakuz66]

Not sure I follow your last post Mtn Don    Are you saying that the expense of the steel plate shouldn't be an obstacle?  Just trying to figure out what you meant?

[Redoverfarm]

rakuz66 I am no engineer but I believe that you would have to use so thick of a plate to eliminate deflection that it would probably be cost prohibitive.  If you have ever laid a piece of 3/8" steel plate on saw horses that are 12-15' apart the plate actually droops in the middle.  It gains its strength in the verticle fashion with it's width.  The U-shaped metal will work but it is expensive.  What will you use to fasten to the metal for trim or ceiling( if not open) as drywall screws or nails will not work.

What would prohibit you from slidding another 2X "up" between the two existing(2" apart beams) and then attach all three together.  Although the intermediate will not be effective carring the load but when added to the other two it will make them stronger and eliminate the deflection they would have.  I see that when you added the two you placed them over the plywood gussets.  That difference of demensions should also be addressed. So your 2" seperation between the two beams is 2 & 1/2" or if double gusseted it will be 3".  By adding a 1/2" ply or 1" board( depending on the actual width) should do it.  I might suggest that in addition that you use Polyuthrene glue to both sides of the filling material to create one unified structural member.

Well thats my $.02 for what it's worth.

[MountainDon]

Sorry.

You may very well think it is expensive when you price it, especially if you can't find a local supplier with a good stock of many different sizes. But it does make for a relatively compact strong reinforcement..

[PEG688]

 Steel in residential work , nah never heard of it ,

 


 

[PEG688]

BTW you'd be wasting time and $$ on something you do not need. That dbl beam you have spans what 9' ?  Your way into over kill here, IF you get that much snow load to crush those the rest of your roof will have collapsed way before.

Flat steel is just about worthless , it would need to installed vertical sandwiched between the beam lams. Your also further adding weight dead load to the beam  and placing steel in the way for nailing S/R , or what ever ceiling materials you'll be using.   

[rakuz66]

Thank you all for the helpful insights    I think I may well be into "overkill" as stated. It wouldn't be the first time. Probably let it go as is, and if anything, slip another 2x10 in between.  Thanks again.  Ready for my next issue??

[rakuz66]

BTW, I figure I should show you guys a pic of what my wife calls "camp cutie". 

[glenn kangiser]

Thanks.  That's nice.

[mvk]

Nice place, where at in the in new york?

But please listen to peg, that beam is holding up sheetrock! If you are worried about snow and i would guess that you should you have to put that beam to work. What i would do is put in some collar ties then nail a peice of 2by on the flat under them and then stong backs stright down to the beam.

Mike 

[rakuz66]

Mike, i'm in the Tug Hill are (redfield).  Take a look at my previous post.  There are purlins running from underneath the rafters straight down to the beam.  The purlins actaully catch both rafters at the ridge.

[mvk]

yep look before i speak, going to learn that some day. Any way I think you could park a truck up there.
Mike

[wingam00]

Rakuz66, is that a "For Rent" or a "For Sale" sign in your "Camp Cutie" window?

Mark

[rakuz66]

Thanks for all the re-assurance Mike and fellow members.  It's my first camp and boy what a learning experince it has been    Actually, all this camp and construction talk has lured me into taking tomorrow and Friday off of work and heading up to camp to put up some more insulation on that vaulted ceiling.  Here's my plan.  I can get a great deal on that insulation board, R-9, I know that would only give me a total of R-28,  still shy, but I can get it REALLY cheap.  Plus, my rafter span w/ 2x8's -24 in on ctr , are maxed out as it is, so I'm trying to stay as light on the vaulted ceiling as possible.  My plan is to put up that insul board ewhich is lightweight and cover it w/ this thin t&g pine I found. 

[rakuz66]

Yeah, that pic was taken before I bought it. 

[Redoverfarm]

rakuz66 nice looking camp.  But I doubt it will stay that way too long as you are in the Construction Mode now.  Wish I was closer as I need some Insulation board.  I can find 3X8 sheets 2" @ $10 but I would have too much waste on 24"OC.

[rakuz66]

I think I may just go right over my rafters instead of between.. I don't think I'll have the room to go in between anyway.