Joist support - InspectionNews

Francis Turak · #1 (**permalink**) 04-02-2007, 04:57 PM

This is in a house I am purchasing in PA. It is an A-frame with an open area above the dining room/living room with a loft and a bedroom on the upper level.

The overall width of the home is 28' and the joists are 16'. I am concerned with the block supporting one of the joists. It appears that the column is in the wrong place. Is this block supporting the right joist adequate? The wooded block is attached with one lag bolt. This installation was approved by the AHJ but one must remember that PA has only been working with IRC for two years. Prior, there was no code.

I have contacted two engineers but never received a return call. Any of you PA guys know of an engineer that will go to the WLE in Lake Erial to look at this?

Thanks
Frank

Tim Moreira · #2 (**permalink**) 04-02-2007, 05:39 PM

Francis,

In my opinion, the bearing part meets the IRC 03 code requirement of:

502.6 Bearing.
The ends of each joist, beam or girder shall have not less than 1.5 inches (38 mm) of bearing on wood or metal and not less than 3 inches (76 mm) on masonry or concrete except where supported on a 1-inch-by-4-inch (25.4 mm by 102 mm) ribbon strip and nailed to the adjacent stud or by the use of approved joist hangers.

Since that appears to be a 4" x 4" member which means 3.5" X 3.5" nominal, then half of that would be 1.75" which it appears to be. So that part would be OK.

The real question is, what is the size of the lag bolt and it's sheer strength? Also what is the dead load of that floor?

I would say that one bolt would be a little lite. It may be adequate for the load it is supporting but I would like to see a minimum of two.

I think this is a question that need more engineering info to answer.

Chad Fabry · #3 (**permalink**) 04-02-2007, 05:54 PM

It's not OK, but it doesn't need an engineer to design a fix either. A Jack stud would probably solve the problem.

Tim Moreira · #4 (**permalink**) 04-02-2007, 05:59 PM

Chad,

Not trying to split hairs here, but I did not say they needed an engineer to design a fix, only that I needed more engineering info for that suitation (IE dead load of floor and lag bolt size/sheer strength.)

A jack stud would be OK in my opinion too, however, if they go ahead with what is depicted in that photo of the 4x4 with one lag bolt, I would want more info as to what I stated. IMHO

Chad Fabry · #5 (**permalink**) 04-02-2007, 06:10 PM

yeah Tim,
I'm with you except I think no matter what, a single lag or bolt, even if the shear is great enough, would eventually allow the scab to shift. Once the scab gets wobbly it's not a matter of bolt shear but of the scab splitting.

Frank was looking for the engineer.

Jim Robinson · #6 (**permalink**) 04-02-2007, 07:45 PM

I think the framer blew it. Looking at the third photo, there was plenty of room to land that cross beam on top of the post and still have the beam traveling back land on it as well. I think the support block will probably hold it, but I would through bolt it twice with some nice heavy hardware.

Are you buying this house new? It looks like new consctuction. The plans probably show the beam landing halfway across that vertical post.

Jim Luttrall · #7 (**permalink**) 04-02-2007, 08:10 PM

I wonder about the spreading of the joist as in missing collar/joist ties. I doesn't look tight now and I can't imagine missing it that much during initial framing.
Jim

Jason Welch · #8 (**permalink**) 04-02-2007, 08:55 PM

I am no engineer, but I am surfing here and I dont like the look of it. It looks as though someone might have made a mistake, and yes a jack stud would work but are you going to keep it exposed? You could put a second bolt in the "block", but my opinion is it will still look incorrect. I know, not much of an answer, but I would feel better if the joists were centered...Good Luck

Gunnar Alquist · #9 (**permalink**) 04-02-2007, 08:58 PM

Seems to me that Simpson Strong-Tie makes a hanger for just this situation.

Francis Turak · #10 (**permalink**) 04-03-2007, 04:11 AM

Thanks all. This is a home I am having built.
The center post is a 6x6. There is plenty of room for the main beam in the center and the two joist to land on the post on either side. I also think that someone made a mistake with the design or framing. I did not post the pictures of the other supports below but they do not land on the steel column in the basement. Although its close enough not to be a problem. Its about 3" off and sitting on a 16" laminated beam and the beam is on the column.

Simpson does make a hanger for this. They were to be installed on the two joists behind above the stairs but the builder missed it. This support was to be exposed as was the joists but now it may need to be sheet rocked in. The spacing between the joists on the column is an eye catcher and will also need to be covered.

I would like to have an engineer take a look but having a time trying to get one to call me back. As of now I told the builder to stop construction until this issue and a few others are resolved.

Frank
New Jersey Home Inspection,Absolute Home Inspection NJ,New Jersey home inspector,Home Inspection New Jersey

Jerry Peck · #11 (**permalink**) 04-03-2007, 10:17 AM

Quote:

Originally Posted by Tim Moreira

The real question is, what is the size of the lag bolt and it's sheer strength? Also what is the dead load of that floor?

I would say that one bolt would be a little lite. It may be adequate for the load it is supporting but I would like to see a minimum of two.

I think this is a question that need more engineering info to answer.

Forget the lag bolt.

It needs a through bolt.

That said, it also needs (as others have said) an engineer to design appropriate repairs.

You could do what the framer did, but with a large piece, through bolted with an adequate number (probably two, maybe three) bolts, staggered vertically, and top it with another piece extending across the top of it all (maybe even a steel plate). It can be done similar to that, but, the critical aspect is having someone design it who can back up their design ...

The structural engineer.

Jack Feldmann · #12 (**permalink**) 04-03-2007, 02:35 PM

The good thing about using only one bolt is you can always rotate the block to adjust the height of the floor above. Looks kind of crappy to me - I'd probably fire the framer.
JF

Phillip Stojanik · #13 (**permalink**) 04-03-2007, 03:07 PM

I'm thinking about a ¼ inch metal gusset plate through-bolted across the face of the horizontal beam ends for the purpose of unification.

But I am not the one to design the repair! Keep thinking structural engineer!

Dan Cullen · #14 (**permalink**) 04-04-2007, 03:38 PM

Nice graphic Phil.....make that a 'T' plate and you'd have a pretty good repair. If it's just a short scab plate you might still get rotation and slippage.

Did anyone consider that there might be a split ring between the support block and the post? A stove bolt would still be necessary instead of a lag but the shear problem could be avoided that way.

Amen to the engineer's signature!

Dan Cullen

Jim Luttrall · #15 (**permalink**) 04-04-2007, 06:15 PM

I am still concerned about the lateral spread.
If you notice in the picture, even the tongue-n-grove flooring appears to be seperated in an unusual place. Are there any cross braces from one roof plane to the other to resist outward spread?