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Clint White
10-19-2009, 04:37 PM
http://i310.photobucket.com/albums/kk433/sihipro/039.jpg

OK ok ok I know this photo is "ripe" with opportunity, but my main question is:

What is the minimum contact required for supporting the end of this TJI?
This is a recent repair and already I see signs of compression damage to the bottom cord of the joist. I was thinking that a hanger properly fastened to the foundation would be a "better" solution.

As you can tell from the photo, this is a "shower repair" gone wild. They cut out a 48" section of joist to access the drain and then they repaired it with caulking. They must of had a HUGE tube of caulking :)

Billy Stephens
10-19-2009, 05:56 PM
http://i310.photobucket.com/albums/kk433/sihipro/039.jpg

, but my main question is:

What is the minimum contact required for supporting the end of this TJI?

.
Clint,

We might be over thinking this Installation .

Noway can a stick of Lumber with 2 Nails supporting this Beam is Correct.

Rim Joist and Simpson Strong Tie, would be my line of thinking. ;)
.

Bruce Breedlove
10-19-2009, 06:15 PM
Where are the other floor joists?

Clint White
10-19-2009, 06:59 PM
Here is a better view...


http://i310.photobucket.com/albums/kk433/sihipro/036.jpg

H.G. Watson, Sr.
10-21-2009, 05:39 PM
Clint White,

Those Prefabricated Wood I-Joists (which may or may not be TJI (R) Series Weyehaeuser branded - can't see the identified side in any photos) have specifications and code reports based on the stamped CCMC Number and date.

They are not allowed to be supported in that manner, and as previously mentioned they also have required spacing. The now missing and previously removed Joists, Beams, or suspected Prefabricated Wood I-Joists, trimmers, have not been replaced or remediated either missing members both parallel and 90 degrees. (I believe you mentioned this was hacked out approximately four feet back from the wall but offered no photo of how it was terminated either). The wood patch filler (again immediately to the left of the plumbing stack where the former PRI or other was ripped out/hacked out also indicative of structral damage to the subfloor OSB or sturd-I. Appears both a parallel member as well as the perpendicular brace were both removed, and that the subfloor was originally glued & nailed (see nails where prior was present), hence the tear-out. Hard to judge the scale but appears the "replacement" or "remaining" PRI was not installed properly, and is an insufficient replacement. The more I look at the photo and study it (seeing old ghosting markes on the foundation wall, subfloor markings, especially on the plate) I am suspicious that originally there would have been a beam installed much closer to the plumbing stack and that the perpindicular PRIs were originally hung from the beam or ledgered and braced and boxed in from the crawl vent.

The lower portion of the I-joist as well as the upper portion which holds the web (the OSB portion) of a Prefabricated Wood I-Joist are called flanges. Prefabricated Wood I-Joists are directional ("up side" and "down side".

Most Prefabricated I-Joists are for dry location use only. Exposure to a moisture problem (evidenced by blackening, the putty/caulk job over the toilet or shower flange and the underside of the subfloor) is also suspect of structural integrity of the subfloor and manufactured wood joists remaining.

Depending on the vintage (date marking) and CCMC number they (TJIs) are limited to strict percentages regarding moisture content, regular exposure while in-use (post construction) and brief periods of maximum moisture content permitted prior to "in use" status (during construction).

Should they actually be TJI (R) Series Weyerhaeuser branded, you can acquire this information from their website library technical documents applicable to the TJIs or if a legacy document is needed by contacting the technical department at (Truss Joist TJI contact) 1-888-453-8358 iLevel by Weyerhaeuser (http://www.ilevel.com/) or mailto:iLevel@weyerhaeuser.com

A strongly recommended referral/deferral to a Structural Engineer (and environmental engineer) as well as a professional plumber regarding the questionable plumbing "repair" as necessary as the integrity of the structural ceiling (crawl)/floor material "TJIs and sub-floor and ability to support the wall plate above may be compromised (permanently due to prior moisture/water exposure). Disclaimer and specialized inspection, analysis and report warranted (Engineer).

If you are interested in what the industry standards are regarding framing and bracing using both sawn lumber as well as manufactured lumber (Performance Rated I-Joists (PRIs) of which TJIs are a trademarked variety, MicroLams, etc.) the APA/Engineered Wood Association has a multitude of free publications available for download in their on-line library. APA - The Engineered Wood Association (http://www.apawood.com/)

Most of the APA library are "pdf" documents and you'll find the easiest is to download as a saved file, scan them, then open them locally using Adobe Acrobat(and save a copy on your harddrive for future reference and quick searching). These documents will give details regarding generalized industry standards, the specific Manufacturer's Specification documents and editions that match the stamping of the PRIs themselves will provide instructions, specifications, limitations which apply including the required engineering for deviations from same.

The crawlspace vent in the photo (visible behind the plumbing repair) and the exposed earthen floor lead me to conclude that this is NOT a CONDITIONED, DRY crawlspace, with the ceiling cavity being exposed, unsealed, it is thus at a minimum a damp location allowing unconditioned temperature and humidity swings, and as such, make the PRIs AND the OSB subfloor suspect regarding constant regulation of MC (moisture content) as suspect to condensation, moisture wicking, visable earth floor, etc.

The suspected dirt/earth on the ledge of the footing where this suport 2x makes for an easily traveled path for WDIs which may find easy entrance via the pictured vent. The presence of fiberglass bat insulation in contact with the earthen floor of the crawlspace also not good as you know fiberglass insulation is easily saturated with moisture, retained like a sponge and wicked upwards like a straw to the structural members above.

Reviewing the second photo, I don't believe this shower drain was original, but a hack job remodel. The presence of the trap after the other lateral would indicate a double trap for anything draining into that lateral. In your region that location (shower drain) so close to that galvanized crawl space louver vent would also lead me to believe this was a retrofit/remodel not an original shower drain location.

I note the OSB shim between the top flange and the subfloor and the lower flange being cracked at the intersection of the 90 degrees offset PRI with hanger. There is no blocking or support to prevent this PRI from buckling, twisting or collapsing towards the vent and plumbing stack and no cantillevier design present in the photos. It doesn't pass the stink test for stick framing and certainly doesn't pass the minimum for engineered lumber framing standards.

I think you probably already know support is required more frequently than 48" OC for OSB subfloor or sturd-I subfloor.

Hope that helps and isn't too tardy for your needs,

H.G.

Bruce Breedlove
10-21-2009, 09:07 PM
HG,

What's with the super tiny font? My tired old eyes can't read it.

Rick Cantrell
10-22-2009, 03:59 AM
"HG,

What's with the super tiny font? My tired old eyes can't read it."

Ditto!!

H.G. Watson, Sr.
10-22-2009, 05:15 PM
HG,

What's with the super tiny font? My tired old eyes can't read it.


"HG,

What's with the super tiny font? My tired old eyes can't read it."

Ditto!!

Bruce & Rick,

I went back and enlarged, but it looks gigantic now to me. Hope it meets with your approval as far as readability.

H.G.

Jerry Peck
10-22-2009, 05:49 PM
Bruce & Rick,

I went back and enlarged, but it looks gigantic now to me. Hope it meets with your approval as far as readability.

H.G.

H.G.,

Did you use font size 2 or 3?

That looks like font size 3. Font size 2 is 'standard' for here and most boards.

The first looked like font size 1.

H.G. Watson, Sr.
10-22-2009, 06:50 PM
First time posted used default size, looked HUGE, so went down one, then after requests went up one. Still looked HUGE to me.

Grrrrowl!

I think I figured it out, seems the default view font size on the browser got changed? Don't know how/when it happened!

Thought it was strange I was seeing HUGE fonts in lots of posts, especially yours Jerry, whenever you cut & pasted a code reference lately, and it just didn't seem "right", then I noticed it happened on my own post and had me thinking.

The browser must have been changed for about a week, funny! This is the only place I noticed the "problem"!

I'm going to change it back to "two", reboot later and see if it looks "normal" to me then.

Thanks for the heads up.

H.G.

Mike Vigneau
10-23-2009, 05:44 AM
I have seen this before. If you hold CTRL and use the scroll wheel on your mouse, you can change the font size in IE or Firefox. In IE, you can go to "View...Text Size" and Select Medium. In Firefox..."View...Zoom...Reset"


First time posted used default size, looked HUGE, so went down one, then after requests went up one. Still looked HUGE to me.

Grrrrowl!

I think I figured it out, seems the default view font size on the browser got changed? Don't know how/when it happened!

Thought it was strange I was seeing HUGE fonts in lots of posts, especially yours Jerry, whenever you cut & pasted a code reference lately, and it just didn't seem "right", then I noticed it happened on my own post and had me thinking.

The browser must have been changed for about a week, funny! This is the only place I noticed the "problem"!

I'm going to change it back to "two", reboot later and see if it looks "normal" to me then.

Thanks for the heads up.

H.G.

Joseph Ehrhardt
10-23-2009, 07:09 AM
If they cut a whole series of joists and theres a bearing partition above this, (depending on the load) a girder would be needed like a LVL, you can use TJI joists as headers across stair wells but typical manufacturers have two TJI together with plywood lammed into all sides of the webs with a 1/8" space at the top for compression and shrinkage.

It appears on the back side of this support a joist hanger is installed with two nails through the top chord of the joist, and with out the plywood installed inside to pack out the plywood web to give a solid surface to install the required amount of fasteners which is another violation.

Typically floor joists bearing are 1 1/2" and girders are 3", also the joist end can not be touching masonry,(which it appears that singleTJI is)and that verticle 2x4 is wicking moisture also.

Amazing what you find out there

Door Guy
10-23-2009, 12:24 PM
Usually a single joist can't carry the load of other joist. Sometimes doubling it isn't enough either. It's hard to tell how long the floor joist are that are being carried by the single joist. Floor load (other than sleeping areas) is 40#'s per square foot live load, with a 10# dead load per square foot.

What's supporting the single joist on the opposing end of the single 2x4 jack stud?

And of course the floor sheathing span as was already noted... I would be concerned about a BIGGER person in the shower causing a problem on this one. Good thing it's not a cast iron bath tub!