beam construction help please

[dug]

O.K, no more concrete- I'm building beams! 20 by 30 1 & 1 half story, mostly to Johns plans with some minor mods. I have sifted through this forum and still am a little unsure how to construct main beams. I am going to build them on the piers as per Mt. Don's suggestion. It is the splice placement that has me a little boondogled. If I understand correctly, the splices should land on a pier and overlap at least 4 ft. Makes sense to me. Unless I am missing something obvious however (likely), there will be at least one double splice no matter how I slice it. Like this-


These are the 2 by's without the spacer wood. I like option A better because it has only 1 double splice and 2/ 7 and a half footers. Sound reasonable?

Question 2: How much should the spacer wood (i/2 in. ply) overlap splices?

Thanks to all for your help and patience

[MountainDon]

Option A looks fine to me. I look at the spacers as being just that, spacing material so the completed beams will fit standard size metal components. Therefore I don't believe it matters much where the spacers material joints fall. Others may argue that point.

A few good bar clamps like the Bessey will come in handy when assembling those beams. When you clamp begin at one end with two 2x and one spacer. Clamp them, make sure they are sitting nice and plumb vertical before you begin to nail.



That's much what I did except I used 4 layers and no spacers. That sat on top of my 6x6 rough cut posts fine.

[dug]

Thanks Mt. Don. That gives me the confidence I need to go out and start sawin' and hammerin'! By the way, I am a fellow New Mexican (just south of Gila Nat. forest)- Don't know why my profile doesn't say that. Anyway, thanks a bunch for the quick response.

[dug]

One more beam related question I had- My beams will lay on simpson brackets directly embedded in concrete piers. I read somewhere on this forum (John R, I believe) that a piece of asphalt shingle laid between the beam and bracket/pier is a good idea. I got a couple of my piers about 1/8 in. off (low) and was wondering if an extra shingle would make an acceptable shim? Wouldn't break down over time would it?

-thanks again!

[MountainDon]

Don't know why my profile doesn't say that.

Under your profile, on the same page where you selected your picture for the avatar, look for the line "personal text". Whatever you insert there will appear under your avatar alongside any messages you post.


The Gila is a very nice area. 

[OlJarhead]

According to JR's notes the spacers should overlap splices by 2 feet and the 2x's by 4 feet.

On my 24 I used 10' and 14' 2x's and 8' plywood for the spacer (which when glued acts like a Glue-lam beam if I am not mistaken.

Don knows his stuff though so listen to him!  I'm always trying to get Don and JR to pop in for the same reasons questions questions!

Cheers
OlJarhead

[rwanders]

One more beam related question I had- My beams will lay on simpson brackets directly embedded in concrete piers. I read somewhere on this forum (John R, I believe) that a piece of asphalt shingle laid between the beam and bracket/pier is a good idea. I got a couple of my piers about 1/8 in. off (low) and was wondering if an extra shingle would make an acceptable shim? Wouldn't break down over time would it?

-thanks again!

Shingle would work ok and shouldn't breakdown----+/- 1/8 is pretty good anyway

[dug]

Shingle would work ok and shouldn't breakdown----+/- 1/8 is pretty good anyway

Yeah, I know. I inherited this disease from my dad. Anything more than 1/16th and I freak out. I love building stuff, but could never make a living out of it.

According to JR's notes the spacers should overlap splices by 2 feet and the 2x's by 4 feet.

Now if I'd have been paying attention I would have caught that!

[OlJarhead]

Shingle would work ok and shouldn't breakdown----+/- 1/8 is pretty good anyway

Yeah, I know. I inherited this disease from my dad. Anything more than 1/16th and I freak out. I love building stuff, but could never make a living out of it.

According to JR's notes the spacers should overlap splices by 2 feet and the 2x's by 4 feet.

Now if I'd have been paying attention I would have caught that!

Maybe not -- I had to kinda dig for it here and in the papers.  I knew I'd seen it before I started our little cabin and searched for it becuase I wanted to be certain too!

one note:  Buy extra glue!  I used typical construction adhesives and though I thought I had enough I actually ran out and had to rush to get more!  Have extra on hand so you don't get caught of the way without enough to adhere the shims and 2xs together!  It's part of the structure of the beam.

Cheers
Erik

[Don_P]

Not many people will try to figure the plywood as anything other than a non structural spacer. You can claim the section modulus of the plies that run with the axis of the beam. The breaks would then need to occur near the inflection points of the beam, roughly close to the 1/4 points of span where bending stress is very low and shear is still fairly low. Then it needs to be nailed off very well. An awful lot of figuring and ifs for marginal gain. Glue in a vertical lamination does nothing for the strength of the beam, it does make it stiffer but not stronger. Stiffer is still better, less bouncy, but ultimately no more weight bearing ability.  Technically you are limited to 1/8" of compressible stuff. I use scrap metal plate to shim where I need to. HTH

[MountainDon]

I never used any adhesive in building my cabin beams. Not a drop or a dribble.  I simply nailed them together about 1 to 1.5 inches from the upper and lower edges of the beam. The information I have from the Southern Pine Council reads...  



No mention of glue at all and nails spaced further apart than most would think.  The nails are there to simply keep the components of the beam in alignment to retain their strength.

[NM_Shooter]

Funny... I sweated over the exact same thing.

Here's what I finally came to realize.  As long as the splices were over the piers, and I didn't splice at the very end piers, it just doesn't matter. 

If you are using galvanized simpson ties to hold the beams to the posts and you are using PT wood, make sure that the ties are the higher grade galavanized material.  I ended up having to put a layer of vinyl between my wood and my clips.

Have fun!  Getting into the framing is the fun part.  Lots of progress and good visual reward. 

[devildog]

I need help understanding Something as well ,on my beam. My general contractor doing my crawl space is going to  make my center piers the same height as my outside walls(I mentioned this in another post), instead of the beam pockets. He says this is the way he always does them.It doesnt really matter to me either way. The part I dont get/cant picture is my built up beam is 2x10s and my floor joist are 2x8 and and he said  I could notch the beam(?). Doesnt this weaken the beam? He said it was allowed by code. does anyone know what exactly this means.

I could see putting in pressure treated 2x10s for beam to sit directly on blocks and 2x8 floor joist sitting on top of pressure treated sill plate.Then Id only have to notch beam 1/2". But I dont think thats what hes talking about.
Darrell

[Don_P]

You are allowed to notch 1/4 depth in the ends of each span, so at each pier. It would be easier and stronger to do it right though  .

[dug]

NMshooter; Sometimes you just need someone to say "don't worry, it will be O.k.

I am not using PT wood and already have PB46 brackets like this-


set in stone, so I hope thats alright. Was going to put some asphalt between the bracket and wood.

[poppy]

So what are you going to do with the bolts sticking out the side of the pier?

[dug]

The bolts are for 2 by lumber, two rows, that will run around the perimeter of the foundation. I am planning to use some kind of metal (corrugated steel?) to eventually skirt the foundation, and the wood will make for easy attachment. If I get tired, and decide it's unnecessary I can always just saw the bolts off!

[MountainDon]

I am not using PT wood and already have PB46 brackets like this-

You don't need PT with the beams that far off the ground.

That metal bracket is slightly clear of the concrete, which is fine. Considering that, I wonder if it is really necessary to use any building paper, asphalt shingles or whatever as a wood/metal break? I'm assuming the beam and pier will eventually be shielded from any rainfall. Maybe someone can point out the error of my thinking if it is in error.

[devildog]

DonP

http://cochise.az.gov/uploadedFiles/Planning_and_Zoning/Southern%20Pine%20Council%20-%20Raised%20Floor%20Systems%20Guide.pdf

fig 22, of page 38 in the southern pine council has  a pic of what he was talking about. I didnt remember him talking about a ledger board till I saw it.
Thanks Darrell

[Don_P]

Darrell, I think I see, he's just removing ~1/2" from the underside over the piers to get it all to line up level? If so I just learned a trick  That little bit would be fine.  The way I like is Fig 24, but line up 10 carpenters and you'll get the whole range there.

MD
I can see mornings when the metal would hit dew point and sweat. It wouldn't hurt to put a barrier there.

dug
If there was a sturdy panel well attached across the horizontal rows of lumber bolted to the sonotubes, you just picked up good pier bracing  .  

[dug]

dug
If there was a sturdy panel well attached across the horizontal rows of lumber bolted to the sonotubes, you just picked up good pier bracing  . 

Yeah, I was thinking that also, but was shy about mentioning it- there are those who think I overthink/ overbuild everything. Probably they are right, but I'm only doing this once.

[Don_P]

Yeah, I was thinking that also, but was shy about mentioning it- there are those who think I overthink/ overbuild everything. Probably they are right, but I'm only doing this once.

LOL  
Nothing wrong with conservative design, I think its a great plan.

[dug]

Success!!! Got my 1st beam done today.


I am sure some of you can relate to my satisfaction of laying my level on the beam and find it dead nuts square with no shimming



Can you say 'Miller time'? (just a figure of speech of course, I prefer a higher grade of brew}

Thanks to all for your help. I probably would have got r' done without it, but not as good- or easy!

[MountainDon]

There's nothing like seeing a spirit level bubble centered like that!  


Q: do you have excess lengths of 2x for the next beam? I ask, as if you do you might consider laying the next beam a little long. Then you can trim it later to the proper length to make a perfect rectangle; align the ends right where you need them, so the floor has 90 degree corners.  Just a thought.

[dug]

          Thats why I love this forum- what a great tip! I do have extra and that makes a lot of sense, I wouldn't of thought of it. Only problem is my 7 1/4 circular saw won't make that cut        (5 1/2 in.) in 2 passes. Any suggestions?