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Richard Thacker
02-05-2009, 07:56 PM
I saw something today I have never encountered and could not explain. Who knows why theses plates are at these positions and why? What is the benefit?

Jerry Peck
02-05-2009, 08:10 PM
Those are hold-down straps and are sized and located according to the load. Some are lateral load resisting also.

The number of nails and size and type of nails are likely incorrect.

Actually, looking at the photos closer, the "number of nails" may be correct, but it would be my 99.94% sure guess that those are gun framing nails and not the specified and required 16d common nails.

Ever watched a framer have to remove all the nails on all those large straps all over the building, especially a 6 unit two story building? Not pretty and not fun, but they have done it.

Then, being as the other framing is already in place, trying to drive 16d common nails in with a hammer presents a real great challenge. Typically the framer only makes that mistake once or twice, then they know they have a chance of getting caught and stop using those gun box nail sized nails.

Jeff Remas
02-05-2009, 08:16 PM
Start reading at R602.10 and you will begin to understand.

Then go here to tie it all together. OK, tie most of it together. Then realize that there were significant changes in the IRC on this subject from 2003 to 2006 and there will be again for 2009 (simpler and less restrictive)

APA Wall Bracing :: APA - The Engineered Wood Association (http://www.apawood.org/wallbracing/index.cfm)

Billy Stephens
02-05-2009, 08:21 PM
I saw something today I have never encountered and could not explain. Who knows why theses plates are at these positions and why?

What is the benefit?
.
Richard,

The straps are there because of the Wide opening ( garage door ) in the wall to minimize lateral movement ( think as in Earth Quake ) foundation settlement , wind loas ect.

The normal structural elements in a wall that perform these functions are missing.
.

Richard Thacker
02-05-2009, 08:26 PM
Jerry,

Thank for the response, but I still have questions. Go figure..

Holding down to what? There are +/- 50 nails in the upper section of the plate and only had room for 2 nails to hit the sill and they were the only holes not filled. What benefit or requirement would call for this application? It seems if a plate were required by some installation requirement I can't see how it would hold much other than preventing the double 2x6s from spreading at the sill (is that the lateral load you refer to).

Do see or know of a practical application for this plate in this situation from the photos I supplied?

Richard Thacker
02-05-2009, 08:28 PM
Could this be the wrong plate for the application?

Richard Thacker
02-05-2009, 08:33 PM
Ok I see it now, I must have not seen the plate extending under the sill. I return to the house to take a closer look at the installation.

Thanks all

Jeff Remas
02-05-2009, 08:36 PM
Very poorly designed and/or built.

Jerry Peck
02-05-2009, 09:18 PM
The straps are there because of the Wide opening ( garage door ) in the wall to minimize lateral movement ( think as in Earth Quake ) foundation settlement , wind sheer ect.


The lateral movement is not only caused by earth shakers, but by wind loading trying to push the building (trying to slide it) on the foundation. Typically those straps are for uplift (wind loading trying to tip the building over) and some lateral resistance perpendicular to the strap. Many straps with lateral resistance are designed to resist those lateral forces perpendicular to the strap and parallel with the strap (the straps are formed differently, that one is a 'flat plate' which can flex back and forth easily).

One thing I see missing (big time missing) as a support for that long spanning header over the garage door opening. it looks to be just nailed to the king studs on each side, no jack studs under the ends of it to bear on. :eek:

I'd recommend a structural engineer on that.

I think that strap may be one of these: http://www.strongtie.com/ftp/catalogs/C-2009/C-2009-p042-p043.pdf or this http://www.strongtie.com/ftp/catalogs/C-2009/C-2009-p044-p045.pdf

Notice that the nails specified are 16d sinkers. It also says, in note 3. that 10d common nails may be used with no load reduction. Go here ( http://www.strongtie.com/ftp/catalogs/C-2009/C-2009-p016-p017.pdf ) and you will see that the 16d sinker is 3-1/4" long underside of head to tip and is 0.148" diameter, and, that a 10d common is 3" long underside of head to tip and is 0.148" diameter.

As I recall, the framing gun nails I measured (I carry a digital sliding caliper with me) were 0.127" diameter, which were used in place of 16d common nails (0.162" diameter) - BIG difference.

It also gives the minimum end distance for the nails, note 4. Minimum nail end distance to prevent splitting is 10 X diameter, 1-1/2" for 16d sinkers and 10d common. That is why those lowest holes do not have nails in them.

Billy Stephens
02-05-2009, 09:51 PM
Edited my Post Correction Wind Load.
Wind sheer is a weather anomaly affecting Air craft. ;) :D
.

Brandon Chew
02-06-2009, 07:35 AM
The number of nails and size and type of nails are likely incorrect.

Actually, looking at the photos closer, the "number of nails" may be correct, but it would be my 99.94% sure guess that those are gun framing nails and not the specified and required 16d common nails.

Ever watched a framer have to remove all the nails on all those large straps all over the building, especially a 6 unit two story building? Not pretty and not fun, but they have done it.

Then, being as the other framing is already in place, trying to drive 16d common nails in with a hammer presents a real great challenge. Typically the framer only makes that mistake once or twice, then they know they have a chance of getting caught and stop using those gun box nail sized nails.


"Ever watched a framer have to remove all the nails on all those large straps all over the building, especially a 6 unit two story building?" ....

If I was the super on that job I would have brought in an engineer to design a repair. It's possible that adding a few more fasteners to what was already there, properly engineered, would have done the trick. Also, if they were pulling out the old nails and then driving slightly larger nails into the same holes, I have to wonder if the "fix" wound up with less holding power than the original mistake.

Jerry Peck
02-06-2009, 07:48 AM
If I was the super on that job I would have brought in an engineer to design a repair.

When I pointed the incorrect nails out to the supt., I did question the ability to 'just put larger nails back in', the supt. did have an engineer come out (large national builder with their own engineers), and replacing the nails was an acceptable fix.

His other fix was not quite as intensive, but the supt. decided he was paying to have it done properly, so he wanted it done properly, thus the framer spent the time and did it "properly", and on all the other buildings (save one other building getting for framing and which the framers guys did wrong, right after repairing the other building too - the framer made his guys pull all the gun nails out and make the same fix), on all the other buildings the framer did it properly.

Rick Sabatino
02-06-2009, 08:17 AM
It looks like a 2x6 was nailed over the jack studs for the door header. Look at the pic of the left side of the door.

Jerry Peck
02-06-2009, 08:42 AM
It looks like a 2x6 was nailed over the jack studs for the door header. Look at the pic of the left side of the door.


Could be. Looks even more that way on the right side, had not noticed that before.

Thanks.

Jeff Remas
02-06-2009, 01:05 PM
One of the biggest issues is that the header does not continue into the corners and stop a the jack studs.

Without having measurements of the door width, garage width, foundation height, ceiling height and overall floorplan of the house, it is difficult to make a technical comment.

Preliminarily without this information, it appears as though the framing may not meet the prescriptive code in the 2006IRC which includes the APA method for braced wall requirements.

If this in PA, an engineer will have to evaluate and sign off on it.

Ted Menelly
02-06-2009, 01:52 PM
If you follow the 2x6 that is attatched to the jack and king studds you will see that there is only one king studd based on guaging the width of the 2x6 at the top view. I never framed with one king stud on each side of the garage door opening. I would also have had brackets from king studds to top plates.

That bracket is fine. I used them all the time along with a lot more brackets of various types all over the place and straps in Floridas high wind areas.

If there was not stem wall and the framing was directly to the slab then it should not be on the double studds next to the king and jack studds but attached directly to them inbedded into the concrete below. The reason they are moved back from the opening was to be more secure further away from the edge of the garage door stem wall.

Rolland Pruner
02-06-2009, 02:01 PM
The straps are O.K. and was most likley required by the engineer with the shear wall, however I sure don't like the garage door header design!!

Rolland Pruner

Wayne Carlisle
02-06-2009, 02:36 PM
It's a poor attempt at the "narrow wall windbracing" as Jeff pointed out.

Looks like the concrete guy did his job...well almost...it's the wrong hold down...4200 lb strap, secured under the rebar. The framer totally screwed up. The header is supposed to run from corner to corner (max 16' opening) with 1000 lb strap between header and cripples, minimum 18".

They tried to make it comply....just didn't quit get there!!!

Damon Sagehorn
02-06-2009, 04:00 PM
Hello,

Totally true "It's a poor attempt at the "narrow wall windbracing" as Jeff pointed out." Supposed to use proper shear anchors that attach to the stud and plate framing as well into the foundation.

Damon

Gunnar Alquist
02-06-2009, 08:48 PM
Jerry,

Thank for the response, but I still have questions. Go figure..

Holding down to what? There are +/- 50 nails in the upper section of the plate and only had room for 2 nails to hit the sill and they were the only holes not filled. What benefit or requirement would call for this application? It seems if a plate were required by some installation requirement I can't see how it would hold much other than preventing the double 2x6s from spreading at the sill (is that the lateral load you refer to).

Do see or know of a practical application for this plate in this situation from the photos I supplied?

Richard,

You probably already have the answer, but the strap is embedded in the concrete during the pour. You can look up the number on the Strong-Tie website.