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Terry Sandmeier
07-16-2008, 06:50 PM
Are there any concerns with this application? Lateral movement? Compression?

Jerry Peck
07-16-2008, 07:34 PM
Are there any concerns with this application? Lateral movement? Compression?

Terry,

You mean something other than what a swift kick would take care of? :)

"Are there any concerns with this application? Lateral movement? Compression?"

Yes, yes, and not really (in that order).

Terry Sandmeier
07-16-2008, 08:08 PM
Jerry

My concerns are, does this post need to be secured to the pier? Is the wood shim proper installation for the post.

Jerry Peck
07-16-2008, 08:26 PM
My concerns are, does this post need to be secured to the pier? Is the wood shim proper installation for the post.

Terry,

Yes and yes (maybe to that last one).

The post needs to be anchored to the footing (I would not call it a pier as it is not a pier) to resist vertical uplift and lateral loads.

The wood shim needs to be of sufficient species of wood to be able to resist the load impressed on it. That is pressure treated, so it is most likely SYP (Southern Yellow Pine), which is a good strong wood used for studs, trusses, rafters, etc., and, as such, is likely to be sufficiently strong in fb (f sub b - I don't know how to make sub text here, this new board does not like html codes, known as 'fiber bending').

If that wood shim is not crushing in much (it may have been installed wet as PT is wet, then dried out, shrinking somewhat), and if it was installed quite some time ago, then it may be okay. Could not really tell from the photo.

Terry Sandmeier
07-16-2008, 09:21 PM
Thanks Jerry :)
This house was built in a county where AHJ are just now catching up with building requirements that are widley used else where. I belive at the time this house was built 2005 it was not required to secure the post to the footing because I do see this with houses built around the same time frame. Does not make it right or correct.
I have framed a few years in my past, but I was taught to never use wood shims in load bearing conditions, so I didn,t. That is why this house caught my attention and I couldnt find any other resource to verify or discredit my thoughts. I still dont like to see wood shims.

Brandon Whitmore
07-16-2008, 11:26 PM
Securing the post to the footing is not required, at least in my area. You would just have to secure the post to the beam.

Jerry Peck
07-17-2008, 05:23 AM
Securing the post to the footing is not required, at least in my area.

How would that resist lateral loads?

I know some areas do not bother with "uplift", however, securing for lateral loads would provided 'some' uplift resistance.

What code are you under?

Brandon Chew
07-17-2008, 06:10 AM
Securing the post to the footing is not required if you are under the IRC and it meets the conditions of this exemption:



§R407.3 Structural requirements. The columns shall be restrained to prevent lateral displacement at the bottom end. Wood columns shall not be less in nominal size than 4 inches by 4 inches (102 mm by 102 mm) and steel columns shall not be less than 3-inch-diameter (76 mm) standard pipe or equivalent.

EXCEPTION: In Seismic Design Categories A, B and C columns no more than 48 inches (1219 mm) in height on a pier or footing are exempt from the bottom end lateral displacement requirement within underfloor areas enclosed by a continuous foundation.

Brandon Whitmore
07-17-2008, 08:43 AM
Jerry,

We are under the 2006 IRC.... New York Brandon listed the exception.

Jerry Peck
07-17-2008, 10:18 AM
Brandon W.,

You are in Oregon ... you guys get a lot of high winds over there too (not the kind going in very large circles that we do, but high winds nonetheless), and there are no uplift resistance requirements there?

I know that right after Hurricane Andrew in August of 1992 the ONLY shingles available which had a high wind speed rating were made up in your area, because of your high winds. I don't even remember the brand now, seems name started with either a M or a W. I remember that when they were installed, the sun down there (in South Florida) would heat them up so much that they were soft and pliable, leaving marks wherever someone walked across them. Once the major manufacturers made some changes and obtained a higher wind rating, that other brand faded out because they were not designed to take the heat and sun.

Brandon Whitmore
07-17-2008, 11:21 AM
You are in Oregon ... you guys get a lot of high winds over there too (not the kind going in very large circles that we do, but high winds nonetheless), and there are no uplift resistance requirements there?

I'm in the Portland/ Salem area market, and we don't seem to have high wind issues. There are areas to the East (Columbia River Gorge) and West (coastal) that do, but winds aren't typically an issue in the valley. The only special requirements are for the way the shingles are nailed into place.
The most common residential framing used in this area is post/ beam construction for the main floor structure. I can't say I have ever seen posts secured to pier pads.

Back to my question a while back regarding shear wall practices and attachment of the home to the foundation..... say the house is properly secured to the foundation, and the shear walls are properly installed, why would interior posts be moving due to high winds?

They say we are due for a big earthquake, structural requirements may change after that happens:eek:

Sorry, but I can't be of any help regarding the manufacturer of the shingles back in the early nineties............

Jerry Peck
07-17-2008, 01:03 PM
Back to my question a while back regarding shear wall practices and attachment of the home to the foundation..... say the house is properly secured to the foundation, and the shear walls are properly installed, why would interior posts be moving due to high winds?

That's why there is that exception Brandon Chew pointed out.

I'm so used to everything being anchored down to resist uplift that i figured, hey, if that moves, it could move the wrong way, but, without uplift and only lateral forces, if the outside the house stays put, there is nothing to cause the inside supports to move, in which case, why to heck even require them to be attached at the top :D (I know, just funnin' with you).

Brandon Chew
07-17-2008, 01:29 PM
I posted this morning just before I had to run out. Here is the reasoning behind the exception to R407.3.

If you have a home built with a continuous perimeter foundation and you have met the shear wall, fastening, and continuous load path requirements of the code, then interior piers or columns are not going to have significant uplift forces on them and they stay in compression. There is no need to restrain the interior columns against uplift. If those columns are lifting up, it is because the shell of the building is already gone, and the rest of the house will soon be joining it.

If you are not in an area of high seismic activity (e.g, you are in Seismic Design Categories A, B or C), then sufficient lateral restraint of the interior columns is provided by the floor frame diaphragm and the "positive connection" between the floor framing, beams/girders, and posts that is required by R502.9. The columns are not expected to see significant lateral forces unless you are in Seismic Design Category D1, D2 or E.

Marc M
09-07-2008, 09:12 PM
How about this connection?

Brandon Whitmore
09-07-2008, 10:22 PM
Oh, that's the new Invisi- Post. Jury is still out as to whether it will withstand the test of time:D

Jerry Peck
09-08-2008, 06:01 AM
Oh, that's the new Invisi- Post. Jury is still out as to whether it will withstand the test of time:D

Brandon,

"Invisi-Post" ... I like that. :)

That's that unique stuff you find every now and then, it is called "structural air".

Even though you can wave your hand through it, 'it is still there'. ;)

I've see "structural air" hold up for very long time, but I never gave it the 'passed the test of time' sign off as it really has 'just not failed yet'. :D

Brandon Whitmore
09-08-2008, 04:02 PM
If I wasn't lazy I would post my teeter totter deck of the day. First time I've seen a deck cantilevered at mid span...................... Are joist hangers rated for uplift??????

Hernando Cortez
01-21-2009, 04:56 PM
How about this connection?

I have seen worst. In older buildings (100 years old or thereabouts) there was not much engineering so overbuilding was common to to point that the joists could carry the entire load even without the middle beam. Many owners , who never enter their crawlspaces, never get to "see" completely eaten -up posts (from termites mostly) and the bare post footings. It does make for an adrenalin pumping experience nonetheless.