Joist hanger question

[xtal01]

I have two spots where floor joists (engineered wood I) will dead end into an LVL.

I also have a spot where two LVL's Tee into another double LVL.

I looked at the Simpon Strong-Tie catalog.

Two questions ...

One ... Where the wood I hits the LVL, they make a top-flange hanger and a face hanger.

They are about the same price. The top hangers have a higher strength. They are also probably easier to use as they will self locate off the top of the LVL

My only thought is, won't they leave a "bump" in the floor sheeting as they sit between the sheeting and the LVL?

Same problem with the hanger for the LVL to LVL connection.

They again have a top mounted hanger and a face mounted (the face mounted is more expensive and will not handle as much of a load).

I could use 2 " (1/4" thick) angle iron with some 1/2" bolts ... not engineered but way heavier than any hanger I could purchase.

If it was just he thickness of the metal, I would not be concerned but the hangers are formed with ridge on the flat hanger part.

Never used these before ... just a bit worried about the floor flatness.

Thanks!

Mike

 

[skeletron]

1. Yes, top hangers can affect the floor sheathing. This is either accounted for in the detailing or framed accordingly. Face mount vs. top-hanger: they can be comparable in loads, the top-hanger is often better in the application where there is some incidental moment or lateral force expected.

2. Not really sure what the second question is supposed to be, so I will just add a caution that the bolted connection you suggested is potentially strength reducing in wood frame. There is a net section issue, rotation issue, and potential tension crack issue that is affected by bolt size and bolt placement. You are better off trying to find bearing type supports with nails/screws.

 

[xtal01]

Thanks so much!

I like the idea of the top hanging ... just might need to take a side grinder and make a small notch in the floor sheathing before I put it down.

For #2 ... probably safer just to use a standard hanger and worry about anything hitting it later. My issue hear was just that the hanger takes up a few inches in the corner where the two LVL's meet. I am thinking the stairs will go right into the corner. This would have the stair stringer sitting on the hanger. Might be easier to move the stairs over an inch or two. Just trying to anticipate problems that may come up in the future.

Thanks ....

 

[Mike Mike]

yep, gotta think thru the geometry before buying the pieces. I haven't heard of floor flatness issues. I assume you will lay plywood floor sheathing plus some kind of finish, which hopefully smooths it out a bit.

 

[xtal01]

I am being wayyyyyy too fussy here.

This is just an attic storage area (just over 1000 sq ft ... with 9 ft headroom).

I ordered the hanging ones ... if there is a bit of a bump, I won't notice it.

They are rated at almost %50 more capacity.

Thanks!

 

[dhengr]

Xtal01:
It is not uncommon to use a router to cut a small recess in the underside of the sub-flooring or wall sheathing to accommodate hanger hardware and tie strapping btwn. beam tops, etc. You see quite a bit of this in EQ design and detailing. I’ve seen some of these guys modify a large circle saw to take a dado set to do this same thing. But, the modification involved removing the blade guard, and that big stack of blades was a real hog. The whole tool and process was pretty dangerous.

You should read up a bit on bolted connections in lumber/timber design. They are difficult to do well on connections like you are thinking of, there is just too much slop and movement in the entire bolted system. You have to pack-out the “I” jst. webs, tolerances in the wood holes and stl. holes and over size clearance holes come into play. End and edge distances come into play, so a 2” angle would be too small. I’d go with the pre-manufactured hangers, with some design and testing behind them.

 

[MotorCity]

If we're talking about the top hanging joist hangers I'm thinking of, these are made of sheet metal at a gage thickness. If you're able to detect any variation in the floor surface where the hangers are located, you're 100 times more perceptive than I am. I'll also add that even if they were to create a variation in the floor, it would still be well below the tolerances that would be expected in wood construction.

 

[xtal01]

I did order all top hangers.

The thickness of the material is not much but they do have a formed rib .. still probably only a 1/16"

I will try one .... if it seems to be much of a bump, I will make a recess ... if not, I can always use my belt sander later.

Thanks!