Hammer beam update and question

[Chainsawmill661]

So I've got two bents up so far on my little Timber frame addition. I've put them up one bent at a time as it's my first frame and I wanted to make sure everything went together well before I cut all the pieces and realized I had made an error

Got the second one up today and it was kind of a nightmare 😂. As you can see from the pic I used the left front 8x8 post of my covered deck as a boom pole, I secured it to the bottom of the deck with a tensioned chain and pulled against it. The porch only creaked and groaned a little lmao. However halfway up on the first attempt a chain slipped and it fell a few feet and went crooked to the slab so we lowered it down to straighten it out and ended up dropping it the final few feet awkwardly. All the joints seemed okay tho (I think😬) so we fixed our chains and cranked it back up. About three quarters of the way up my tractor supply pos 2 ton block and tackle broke some mechanism on the pulley chain and it was stuck hanging so I dug out my dad's old rustly block and tackle and managed to get it the rest of the way up with no one dying.

Anyway, all this to say I'm not entirely sure how to get the last bent up as I can't use my porch post since the middle bent is in the way now. I had an idea but I'm not sure how stupid it would be. Could I finish this half of the frame, drop the cross beams, purlins, and long side braces in, and then lift the last one from the top of the middle bent? I feel like that would be at least as strong as my porch but I don't want to ruin my joinery with all that weight. Any thoughts? I may break own and hire a crane but Im not even certain I could get one down my little driveway, and there's not much room for manuvering around. I have a tractor with a loader I could rig a boom on it but the other bents are in the way 





 

 

[Jim_Rogers]

First, I would try and figure out the weight of the bent. That way you'll know what you've got to lift.
If you're lifting it fully off the ground/deck then use the total weight of the timbers. If you're leaving the post bottoms on the deck and pivoting off them then you can reduce the weight by 2/3s as part of the load will be supported by the post bottoms.

Next, you'll need to get good rigging that will not break under that estimated load.

You can then either make a gin pole or a pair of shear legs. You can tie off your rope/lines to the existing frame, if it is secure.

Erect the lifting system so that the bent can be raised into its position safely.

Good luck with your project.

Jim Rogers

[logman]

I would have raised the middle bent and secured it up against  the first and then raised the end one and spread the middle one back into it's position.  You could rent a hand cranked Genie lift to get it back into position just taking enough weight off to move it.  

[Chainsawmill661]

Doing some back of the envelope estimating from my material in figuring they're in the 1800-2000lb range using 3.75lbs per bf for green yellow pine, which is a number I pulled off Google I'm not sure how accurate that is. They've been in an air dry stack for a year so they are definitely not quite as heavy as when I took them off the mill.

To be clear the 2 ton hoist itself didn't fail, but the pull chain mechanism broke so I could no longer raise or lower the chain. So I don't think it failed due to the weight. with the legs on the ground the whole time I don't think there's any way a 2 ton hoist wouldn't be enough

Looking at it again out here, I think it's possible I can lay the final bent down with the peak pointed towards the other  bents and pull up that way without moving the middle bent. I think with the open middle of the hammerbeam theres just enough clearance to get through but I'll have to math it out or  build a template to be sure. The bents are spaced 12 feet apart and are 16ft tall so there's only 4 feet sticking past the center line of the middle truss. Here's hoping

[Hilltop366]

If you assemble the last bent with the bottom of the post where they go and the rest of the bent on blocks over the ground and the bottom of the post captive so they can't slide towards the building or to the side then lift the top up a ways with the tractor and put blocking or temp post braced together you will have bypassed the hardest part of the lift without using the block and tackle then the block and tackle will finish the lift with a lot less strain. 

For a pulling point you could run a heavy rope or chain from your original point across the bent inside the top triangle and put a pole under it angled back to brace it?

Just ideas, play safe.

[Chainsawmill661]

Hilltop, I like that idea but I'm not sure what you mean by the part about the angled pole, where would the pole go?

[Hilltop366]

The pole would brace the middle of middle bent, so from the bottom of the top triangle of the middle bent to the ground at a angle towards the building. Another option would be from bent to bent (in between so you are no depending on fasteners to hold the load) then to ground or the building if it will do the job.

[Chainsawmill661]

 

 

 



Finally got a little more done, last bent cut and raised. I did what Hilltop suggested in the last comment. Took several chains but we got it up

All that's left now for the frame itself is the drop the purlins and top plates between bents 2 and 3.

Which has got me to thinking about enclosing it. I'm priced out of sips so  I'm intending to wrap and strap on the side walls and build a regular stick stud wall on the endwalls to frame my windows in. As you can see the plan didnt have girts so I didn't add any, but I'm thinking now I will need nailers for the tongue and groove, or could I be okay spanning the 7 feet 11 inches from the bottom plate to the top plate with vertical tongue and groove,  and adding my insulation and strapping to that?

I'm guessing that wouldn't be stable enough, what then is the best way to add girts with the posts already up? Half lap? 

 I do not like the idea of girts from a looks perspective,  as it's a dust collection surface from the inside of the building.  Is there anyway around having girts and still being able to do wrap and strap? Maybe 2" t&g instead of 1?

[beenthere]

or could I be okay spanning the 7 feet 11 inches from the bottom plate to the top plate with vertical tongue and groove,

Do you feel lucky?  ;D

Don't find a location in your profile, so answering is tough to do. Can you make 2" t&g ?? Which yellow pine? 

[Chainsawmill661]

I always feel lucky!

My location is gulf south louisiana

My local sawmill can make me 2 inch tongue and groove they usually sell for bulkhead. It's more than twice the cost tho. And yeah,  southern yellow pine

[Don P]

Make the girts insulation thick and install them in that layer? You'll need to temporarily hold them in place with some spacer blocks as the T&G is applied. 

[Chainsawmill661]

Make the girts insulation thick and install them in that layer? You'll need to temporarily hold them in place with some spacer blocks as the T&G is applied.

This seems like a good plan.  As much as I liked the idea of a solid envelop of insulation,  I'll probably do this

[Hilltop366]

I'm thinking "the first layer of insulation thick" is what Don P is talking about?

That way the next layer covers the girts.

[Chainsawmill661]

Okay,  I think I understand.  It would be something like this? I'm a little unsure how doors would be installed with this system though



 

[Don P]

I had meant to breach through 4" of insulation, i think when you check the girt(s) with a 20 psf wind load it is going to be more than a 2x. Check it, I'd like to be wrong.

[Hilltop366]

I stand corrected.

[Chainsawmill661]

I had meant to breach through 4" of insulation, i think when you check the girt(s) with a 20 psf wind load it is going to be more than a 2x. Check it, I'd like to be wrong.

How would I check that? Sorry I'm new to a lot of this stuff. If there a table I can compare spans to wind loads or something or do i need an engineer to math it out?
 And if I did breach through 4 inches of insulation what's the best way to secure the girt to the posts? Timber screws?
In any case, I'd rather overbuild than underbuild since this is hurricane country. 
Im not entirely opposed to visible girts on the inside of the building but of course there's now the issue of getting them in there since the bents are standing. So, Going back to an earlier question, could I use a 4x5 or something and half lap it onto the outside of the posts to get a flush surface with the posts? 
Thanks for all the help 

[Jim_Rogers]

You can add a timber to the standing from between post with this:



 

Any one of the bottom three are slide in joints. 

Jim Rogers

[Don P]

DanG!, It was a novel too  :D poof.

It's the same as a roof or floor, the wind acts normal to the plane .. it hits it square on. You can use the hazard tool above, cross that with the table in chaper 3 of the IRC and get a design pressure.

For an example,  Assume post to post is 8'. Sill to underside of plate is 8'. Use 3 2x4 girts horizontally @ 2' on center. The area tributary to each girt is 2'x8'=16 sf. I use 20 psf wind pressure for most stuff, that should be a little north of 100 mph in the tables. 16 sf x 20 lbs/sf = 320 lb wind load per girt. Wind, its a uniform load, use store bought #2 SYP 2x4's and this calc;

Design for Bending (forestryforum.com)
3 or more members
10 minute wind load
2&3x4
no
no

The girt deflects 1/2" at midspan, I suspect the built assembly is stiffer than that part and that your spans are smaller, but you need to point to some known structural something. at .5" in ~100" you are at 1/200 deflection. I think code for a wall is 1/180 so it does pass.