While the tone of this video may sound like I am against the use of J/L bolts period, there isn't really much documented evidence I've found that shows failures in wood residential or commercial construction as a result of J/L bolts. J/L bolts are still technically allowed in the residential code and your building official may not have a problem with them either. The intent is to pass information about the issues other industries have had with them that I think might be a good idea to implement in residential construction. If you've attached walls to concrete using J/L bolts, it's ok :) I think J/L bolts have a place in very specific circumstances, however I do think there are much better options that are easier to utilize and do the job much better.

I'm also a licensed structural engineer specializing in residential and high end residential design. I don't agree with the conclusion to substitute post-installed options for cast-in-place anchor bolts. While most contractors are going to love your video and always ask for a post-installed substitute, it's not a one for one exchange. The capacity of post-installed options is substantially less than cast-in-place anchors. Not to mention that breakout is of equal concern and maybe even greater depending on construction practices and how the install went. Overall, substituting post-installed anchors for cast-in-place simply because they are easier to install for contractors is not enough to change industry standards. If your issue is with the breakout capacity being limited to the top of the J, then you can always substitute a straight bolt with a plate washer sandwiched between two nuts for substantially higher capacity. I think this video leads people astray.

J-bolts, with a linear rebar, running between them, laying in the "J" greatly increases the pullout resistance, and avoids wet setting issues.

As a fellow engineer, I would have expected test data to prove the point. Mechanically, i don’t see how the 2 post pour options would provide more holding force. The cam lock is worse. The epoxy is the only solution that distributes more load to the lateral surface.

In the bahamas we tie J bolts to the belt steel before forming up and pouring the concrete belt. So pulling them out would be impossible.

You generally don't want to use wedge anchors on a foundation stem wall (which is most of the time). The distance from the centre of the bolt to the edge of the concrete is too short to comply with the manufacturer's minimum requirements. You can even potentially blow out the concrete. The wedges push out and if the concrete is too thin, it will blow out. The close edge distance also substantially reduces the capacity of the bolt.

Nice presentation and clear information, mate! However, I would avoid mechanical anchors, which induce increased stresses on a small section. I highly recommend the J & L bar as an engineer. But, as you said, it's more convenient to use other types of anchors for site difficulties. Chemical bond anchors are a good alternative after concrete casting, but, the downside is that it's expensive. A good engineer will sit down with his builder and discuss preferred construction methods and a budget, as some builders have more confidence to choose specific options.

I believe that this movie was created as a promo for the post-installed anchor industry. The code requires CIP anchors to be emended 7” min. which means that overall length of the anchor must be more or less 11”. Can you imagine how much the 5/8” diam. KB-TZ2 SS (they do not fabricate HDG stock) anchor of this size is going to cost? It is a major impact on the construction cost. Good luck! So, CIP anchors are here to stay. In addition to what I have said above consider the following: 1. To install post-installed anchors into the sill plate (review the ICC Report #4266, for example) you need to provide a continuous special inspection at the site which can only be performed by an authorized third party, special inspection agency. I can guarantee you that it will triple cost of installation compare to the CIP anchors. 2. Please also show correct anchors with standard 90 Deg. hooks, not what was shown at the beginning of the video. What you showed was a substandard anchor with a short tale. See ACI318 or CRSI manual for correct dimensions. Good luck from California, SE.

None of the options you mention spread the tension load across concrete. A J bolt hooked on a horizontal rebar will far exceed everything for resisting uplift forces. But I definitely agree having to preposition the anchoring is a pain in the butt.

Good video. We see L bolts in commercial all the time but they aren't those little things your are showing. Not only are they bigger in all directions, they are usually paired with the horizontal rebar, the "L" hooks under the horizontal. In residential, IF you have enough wind to pull out a series of L bolts, you likely have much more important things to worry about. As an PE, you likely know the cause of failure is rarely one thing, the system failed not just one thing. For the sleeve or wedge anchors, the only person that knows if they "grabbed" or not is the person who installed it unless an inspector is going to walk around with a torque wrench. Epoxy is good IF the installer, usually the unskilled crackhead cleans out the hole correctly. I never messed with screw in anchor bolts Engineers need to stop trying to reinvent the wheel and just make a proven practice better. Make the horizontal part bigger and/or tile them to a horizontal and call it a day. 30 years as a commercial CM.

Practically, the post installed anchors would not be as strong as the J anchor bolts. Since you have to drill a larger holes with a lot of concrete dust, if test on sites, the J anchor bolts would have a better performance.

Hooray for you! Retired structural engineer. Never used a J bolt in my career but then again, I designed industrial structures. Anchor bolts were an issue from the start of my career until I retired 6 years ago. Mostly used threaded rod with nut on the end. You know the ACI has done a lot of research on this issue with pullout cone analysis, etc. J bolts are horrible. Kudos to you for highlighting this issue!!

How 'bout you show us the threaded and epoxy anchors being pulled with your test jig like you did with the L bolt? I'm having a hard time believing the concrete wouldn't break and blow out in the same way or that the bolts wouldn't just pull out. I just want to see it. Everything looks good on paper.

I recently replaced a section of rotted sill and rim board on a 50year old house and discovered the block wall foundation had zero anchor bolts. The house was resting on the foundation and had not budged at all. Most barns in my area are sitting on stone foundations with mudsills in various states of decay and have no mechanical tie to the stones. I live in new england where we do not have tornadoes or hurricanes but it seems like this issue of anchors bolts just gets beaten to death.

I didn’t know J-Bolts were used to withstand uplift loads. That is why engineers specify hold downs with specific uplift capacity based on the conditions or structural calculations results.

I was trying to find out how the wedge anchor worked, thanks for taking the time to explain their system. :)

Hi Jay, good stuff. Just want to add my two cents. Typically L & J bolts are used for shear load, not uplift. Secondly, the wedge anchor might cause concrete spauling with close edge distance installations. Where the screw anchor at 1 3/4” isn’t a concern.

This was by far the best video I found on anchor bolts. My next step was going to be finding the ICR code regarding them. The video took care of both. I might get banned from the channel, I plan to use L or J bolts for my project, lol. I don't have a hammer drill so an L or J bolt would be the easiest and most cost effective in my case.

I've spent most of my career in the heavy industrial sector of structures. Almost exclusively plated rods. But for lighter work, post pore chemical anchors have never failed me. I love that they prevent water and chemical intrusion into the drilled hole. Great vid. Keep it up.

In my experience . Ever notice the slot on a CMU unit . That is where an L is supposed to be hooked . Not too many masons take the time to do that . Most with just push one down and core fill with broken cull and slop mortar in the cell .. They all wiggle . On concrete .. Most will just push one down and wiggle it , most are out of plumb and require knocking straight which shocks the concrete , On the perimeters of monolithic slabs , Cracks the concrete and sometimes breaks off the concrete , The threaded anchors are fine . But they can shatter the perimeters as well when tightening thus rendering them useless.. In the field " anywhere besides and edge " . Epoxy has it's attributes as well . Drill the hole , blow it out and squeeze in the epoxy ..Yet in my experience .. If the hole has the least little dust .. It can be pulled up with ease when tightening So they really need to be cleaned out with with a damp cleaning tool . I find it hard to believe a sleeve or expansion anchor is better than a L bolt . Drill the hole and pound them in . They can be pulled up and out when tightening . So are you saying an L bolt can pull out easier than a sleeve. Wedge It ?? .. In a perfect world .. The J bolt is supposed to be hooked under rebar.. But few put the effort into making sure they are hooked and few put the rebar in the running location . It's always Blow and Go . In my experience I have worked on some " Beauties " When installing the mudsills . The carpenters would just use cut nails , case hardened , or a sinker . Basically worthless . Nailing into a CMU cell that has been filled with cull brick and topped off with a skimming of mortar !! LOL . . Many plates shook and made it hard to layout with plates doing The Shakes .. I remember watching on the local news , Houses floating off their foundations completely intact during a flood . LOL . Just recently . I couldn't work for a stupid builder . Had to leave . They were building basically a shed " Office " for what I called a Hooverville .. They were using anchor straps on a monolith and secured them to the plates with ... Aluminum roofing nails !!!! .. I jokingly suggested " Why not a thumbtack ?" they are basically the same . It wasn't until they said I was insane about setting a gatepost . They dug a 2' deep hole and set the 6x6 in and powdered in a bag of concrete and wet it .. Dry Packing !! . I said it aint worth a pile of dung . I even said " If drypacking is so good .. Then why don't concrete trucks just deliver the powder when pouring a footer ?" Imagine the fuel savings !! .. Next day I helped install the gate with a wary eye . I knew what was going to happen . Shimmed the gate in the hole and attached the hinges . Released the shims and the gate lurched in 2" .. rendering the gate inoperable !! LOL .. " Well You gonna have to fix that " .Years ago I had a saying " Why do it right , when you can do it twice and twice is twice as nice and a third time . Moi !!" .. I told them .. Here is the solution .. Did the hole bigger ! make an elephants foot hole , screws in some deckmate screws into the post . Like talons on an eagle and mix the concrete this time .. " Well we'll need a wheelbarrow !" .. Nope . Just a small tarp or piece of housewrap .Break the bag of concrete in the middle . pour in the water and pick up the corners and agitate !! . then sluice it in !! . I refused to participate in their stupidity anymore . I asked the builder " Is this the type of crap you build ?.. Count me out !!" See ya .. .. When I was hired .. He told the other guys " I don't know if I should hire him .. He's a super carpenter " .. I just wanted a little work while I am fighting Stage 4 cancer . I didn't want to run a crew again . I can't !! but I can be one hell of a hired gun when I am not sick . A few video ago .. You had a video about a balloon framing .. On one of this Builders projects .. They framed an 8' wall . and then framed atop it to the gable rafter . It shook back and forth 5 " with minimal effort . . I said "It should have been balloon framed " .. He said balloon framing is against Code !!! .. Huh !! .. The balloon framing he was talking about is where 2 story walls are framed and joist are sistered along the sides of the studs .. It's doable but anchoring must be perfect . I don't even do that'' Thats ancient . .. I told him .. It will continue to shake and poses a problem . The interior was vaulted .. I suggested .. at the very least .. stiffen the plate line with a LVL laid flat on the plate .. Turn it into a shelf !! . of put a perpendicular shear wall at midspan .. Use it for concessions in the future . Anything !! .. He said the collar ties will stiffen it and I was a jerk and said " No it wont" .. At these times .. You just bite your tongue and hope your eyes don't roll .. I ramble .. I have 40 years of experience and have seen most everything .. I have seen products that were revolutionary at the time , That ended up problematic . Most in the construction business are just about . Get it done with the least of money ,effort and hope nobody notices .. It's Bang Bang Bang .. Money Please . Most carpenters just follow and many don't consider the entirety . They were told and did . Check Please . . I have seen paid off Building Inspectors , Engineers that were hardcore and others were Slip and Slide . Architects that levitated and could do no wrong but had 100 mistakes per plan .Others that were sharp as a razor . Most custom homes have a myriad of problems looming in the years to come .. Remodeling business is booming

You just earned a new subscriber son!!!🤙🏼 I’m a 35 year GC from South Florida where strong winds and Hurricanes are a big issue in my field. Inspectors are hard on us with matters such as the one on this video. And you’re absolutely right about these concrete anchors!! I appreciate your tips and I will definitely search through your other videos. Thanx man!!!🤜🏼🤛🏽 and keep up the good work!!!

Hang on here. I learned how to do foundations from an old high school buddy in the trade. It was not covered in engineering school. Rebar is a big deal. The use of rebar I’d carefully documented. What I like to do and granted it’s tricky, is to slip the j bolt into the mud and then rotate it 90 degrees and slowly lift up. What happens is the bend is now under the length of #4 rebar. You can feel it catch as you fish around. Of course, one of the biggest problems is to put J bolts in the wrong place. Code dictates the placement schedule which sometimes interferes with the framing and sill plate. This is a pain. So the foundation drawing should show placement of these bolts. When needed, I will augment or repair as needed using a Titan bolt by Simpson.

Good to hear, I'm digging and installing new footings for my garage previous owner never did and all the sills are rotted away and I didn't put in any J bolts so going to go for the 3/8 in hammer in anchor bolts. I use an Milwaukee SDS drill sooo much quieter than the old hammer drills.

I really enjoy your videos. Very helpful for my learning and you have a very effective way of presenting your material !!

I watched this on 1.5 speed and enjoyed the way you explained the information. Thanks and god bless

I'm a mechanical engineer, building my own home. I used L bolts as called out by the structural engineer, but upgraded to galvanized for a few extra bucks. In a few locations we needed additional bolts such as around doorways so we installed Titen bolts (screw anchors) in those locations. I loved using the Titan bolts and they were very easy to install. The concern I have is the design heavily relies on the integrity of the thread. It seems as if the thread would be the weak link over time as the thread corrodes and rusts. The thread is fairly thin so it feels as if it could decay relatively fast. I would suspect the galvanized layer is also somewhat compromised as the threads are twisted into the abrasive concrete. I wonder what kind of life span these bolts have been tested to.

THANK YOU!!! Very helpful for my upcoming project!

I like this guy and he keeps explanations clear.

Thanks for making this very clear.

Text at 1:51 states: “J/L bolt failures have been linked to bolts slipping off the concrete along the vertical shaft.” I don’t know what your source is for this assertion, but it does not withstand theoretical scrutiny. First off, the bolt shown has clearly not failed; it is the concrete that has failed. Ideally, you actually _want_ to allow axial movement of the bolt w.r.t. the concrete at all points along the bolt, except, of course, deep at the fender washer or “J” or “L” area. Remember, concrete is strong in compression and weak in tension. Also keep in mind that the anchor bolt (as with all elastic materials) there will be elongation resulting from the axial force. If the bolt is bonded to the concrete, as the bolt is loaded, part of the load will be transferred to the concrete. Near the surface, you want all of the tension to be borne by the steel bolt, and none by the concrete, lest we see the failure type shown at 1:29. This why tape or tubing for the upper portion of the bolt is sometimes specified to prevent bonding to the concrete.

I use the j-bolts as only to resist sliding on the foundation. I use QuickTie cables for my uplift counter measure. I am given the data to design with. You are so right about having only the 90 degree leg as the part with the load on it.

Good info. I used on my deck but will not use for my cabin. Thank you sir.

Excellent video. Thank you for the information.

I used all-threads with a washer and nut at the bottom in combination with two horizontal rebars running along the top of the foundation wall. For anchor plates I used custom made PL 5x3x1/2 with a punched hole. This size works well with both a 2x6 and a 2x4 wall plate and spreads the load across the hole width of the lumber for increased capacity. I also doubled up the wall plate in the bay with the anchor to increase the bending capacity of the wall plate. This also gave me more area for attaching the sheathing, which makes for a better load transfer. The problem with cast-in anchors is that one has to know exactly what the framing will look like to place them correctly. My anchors were installed pre-pour and concrete placement did rotate some of the anchors but they were easily straightened with a piece of pipe once the concrete had gained strength. The anchor threads need to be protected during the concrete pour so as not to gum them up. I used short pieces of PVC pipe with a duct tape cover. I have more confidence in these anchors than in any commercial system. It was a lot of work but this was for my own house and I wasn't going to cut any corners.

This was super helpful. I wasn't aware of these.

Great video. Thank you!

My experience is that drilling is easier and way more accurate without having to hang out material in the sill plate. Post drilled threaded bolts are commonly used in pole barn construction, and are more than adequate to hold the structure to the foundation. Having said that, I use j-bolts per code then add extra drill ins so that I have an anchor every 32”.

I just came across your channel. I'm sorry to see that you have not continued but considering the last few years I am sure you have been an extremely busy engineer. I wish you the best. I wonder if you can explain considerations when building a single wall (2x6 16 o.c.) over 12' tall. God bless you.

Great info. Thanks for the vid, I Believe the Epoxy anchors are still required to have a Deputy inspector overseeing their install which will add to the cost. But both are great anchoring systems.

Thanks for explaining!

Hey man just found your channel, really interesting and very simple to understand. I’m sure you come across cantilevers in buildings, can you make a video showing a cantilever home, where part of a bedroom is cantilevered, and how one would attach a deck to the cantilever.. I see people shockingly attach their deck ledger board to the outside of the cantilever with no load bearing beam/post.. certain failure will follow with a heavy snow load or multiple people on the section of the deck attached to Cantilever.. definitely needs to be addressed!

I love your KZfaq channel. You are a very smart person . Miss . Linda 💯

Very insightful video!

I spent the morning today hammer-drilling holes for expansion anchors in a new build. The contractor specified expansion anchor bolts (in addition to Ramsets) on all the interior and exterior wall base plates.

Very good presentation. I will be using epoxy-threaded anchors for my home project.

I agree somewhat, but for a house the L bolts should have plenty of hold down. Also smooth shank vs threaded? Here in Australia its all post installed anchors except for stuff that is big. What I mean by big is say a radio tower you might use cast in bolts but weld them to the cage in some cases, but a tower is also side loaded which helps the L bolt. As you said chem set anchors are very strong but they basically have a 75mpa resin in a 20 to 35mpa base material so you're still limited by the base material being concrete at say 20mpa. This means cast in bolts are the strongest, not L bolts but rather threaded rod. What I do is if I have a square steel plate I need to anchor if I can set it in before the pour just make a plate in the steel and one out to align the bolts and now one bolt is achored with a plate and 4 other bolts.

I agree the j bolts are harder to install but they are probably cheaper too. And no way are the drilled in anchors as strong. I like the drill in anchors because I am not a pro, just a homeowner.

Thanks for the useful information 😊

Great information! Thanks!

Great video -- hope you do more content in the future.

Good video Jay, also (for machinery installation) The Gas Machinery Research Council (GMRC) said that L and J termination should be just for auxiliary equipment

Thanks for such an informative video. What would you advised to attach a shed to an existing hollow concrete block home?

Those 2 post vehicle lifts come with 5/8 inch wedge anchors and need 4 inches minimum concrete thickness, recommended 6 inch thick. I used 12 inch x 3/4 j bolts thinking that had to be better than 5/8 wedge anchors. I sawcut the concrete out, dug down 3 feet, tied rebar, tied the j bolts under the rebar, vibrated the concrete. I was a little nervous about 5/8 wedge anchors holding up 10,000 pound vehicle lift.

Interesting video, the comments contributors are as interesting. I've used L bolts for over 50 years. I like them but one needs to be careful where you place them.

Nice video. But, I'm not sure if I agree completely. Firstly, it is not difficult to install J/L bolts. Those in the trade have been doing it for litteraly decades w/o issues. Secondly, where is the proof (aka testing video) showing J/L bolts failing due to uplift forces? And, thirdly, I deal with structural engineers all the time and most (if not all) of the specifications for AB have been the typical J/L bolts. Of course, using the screw-in bolts, and the expansion bolts are also good choices if the concrete is already poured. Otherwise, I don't see why a structural engineer would phase these out when they are perfectly fine and gets the job done 100% of the time (provided its new poured concrete). Thanks.

Great video. Thanks.

Would like to see your hypothesis in a lab setting using all the requirements for a complete evaluation of all anchors vs the one you're pushing.

That was very interesting.

Thanks so much for confirming my suspicion that j-bolts are very difficult to install correctly.

my cousins husband worked for Napa and went to a trade show where they demonstrated using the epoxy --seems the epoxy Vapor extends out into the concrete expanding the area of adhesion.. other types of hold downs pulled out with little concrete damage the epoxy consistently pulled out a 4 to 6 in section of concrete!!!!

Good stuff! Thanks for the teach, teach!

I have used J bolts for 50 years. Never had any type of problems and I will continue to use them. Just because screw bolts are new doesn’t mean it’s better. Expansion bolts cause to much long term pressures on very fragile concrete. We pour all our foundations then insert the J bolts and will continue.

J bolts are the way to go with new construction as they prevent drilling concrete and dust exposure.

I’d recommend using epoxy with tapcons. I drilled the right size hole and used them but they free spin in the hole after tightening. It’s a basement wall non load bearing so I’m not worried about it. I put the studs in after the sill because I didn’t have room to work with so it’s really tight to the floor and doesn’t have any lateral movement. If I did it again though. I looked for the epoxy at Lowe’s made for anchors, none in stock. I don’t know if all epoxy is the same or not.

It's one thing to talk about using other methods of securing mud sills, but quite another to get them passed inspections. My advice is to ALWAYS check with your local building dept.

Good info

A screw anchor will never end up in the middle of a stud . You also don't have to lift the walls up and over the anchors. Stand the wall up square it and pin it to the foundation. Post install anchors are great😎

Love it.

What do the tests show if you throw a washer over the J before installing it? (This is assuming you can get the concrete around it without a big air gap.)

J bolts which are wired to and hook on a horizontal rebar before the pour do not pull out. Rebar threading is also a good option which is used where I live in California.

I have used many AJs and other anchor bolts and I would always use cast in place first given the option.

I discovered those Titen HD bolts/screws(?) recently. They are so much easier to work with than J bolts. Wish I knew of them years ago.

Good video! Another reason to be a Garth fan!😂

J anchors can also be set before concrete by suspending them in piece of lumber across the concrete form. Little extra work, but more confidence they`ll be set right.

In California all post-set anchor bolts require deputy inspector, so Ive only used when there is screw up and bolt is missing or misplaced. Also J/L Bolts are not used as for holddowns in shear wall . just to keep bottom plate from kicking out and against minimal uplift /shear forces. Much longer curved / S shaped and inward angled bolts used for holddowns , SSTB16's ect...never j bolts. Also always use Simpson strongtie anchor mate holders make setting all bolts pre-pour easier.

When I built my garage I did the j bolts on the block. However, I think both are fine, they both prevent uplift but at some point if the force it to much then both ultimately fail. It’s still better than nothing on the sill.

As others have pointed out. Wet set anchor bolts should be directly tied to the horizontal rebar thus distributing the load.

It amazes me how many people have left comments saying that A: they're not an engineer, and B: cast-in anchors are obviously stronger than post-cast anchors could ever be.

On the Japanese video, they also use the L bolt, and also as a way to hold parts of the sill down temporarily while straightening the rest of that sill to the chalk line. So, it's not useless to precision nerds. Maybe I could add a few screw or wedge anchors on the 4 corners of the sills after if it pleases you.

I was a tool and die maker for over 40 years in some very heavy metal industry with heavy machinery anchored to concrete floors...i have seen a lot of red head anchor bolts pull out of floors....these anchors bolts were sometimes inch in dliameter in 8 inch concrete pads....seen them get jerked right out by heavy equipment, but never a j bolt of he same diameter...seen them shear but never pull out

Very nicely done. Thank you. raphael nyc

I liked your video, and I understand using it in plain concrete settings. However, recently I bought a house that is sitting on a cinder block wall foundation. The house is on a slope, and half of the house is sitting on concrete foundation ad the other half is sitting on cinder block walls.The cinder blocks are over 10 feet tall. I think it would be easy enough to put in j bolts inbetween the cinder block joints to fasten the sill plate, but since the top of open and exposed on the cinderblock, I am not sure what else I could do? I could try and fill in the block walls at specific points, but I think that would take a lot of concrete, and I am not sure if it would settle correctly. I am not sure if there is something else out there to use?

What about tying the L bolts to horizontal rebar prior to pouring? I’m building a steel PEMB and was thinking having the guys tie the 1/2” rebar in the beam to the bolts.

Sir, I have been building for 60 years, dyna bolts regulrly fail, scew in anchors great for hold down or temporary formwork fix to adjoining concrete, rag bolts have stood the test of time in low stress engineered situations. This sounds like more white board commission for DEI academics have now got hold of the construction industry. Start using Ramset concrete insert bolts where you can run a continuous line of deformed rebar through them that integrates with the cocrete and rebar design. Heavens help the construction industry with this level of wooly thinking, talk about engineering loadings what we have going on here are mutational loadings . Welcome to the harsh roadmap of reality! KPP nz

You showed one pull-out test, do you have the data that shows the best anchor that resists uplift?

There’s the structural design and there’s the builder. In the garage at my home growing up, we widened the garage and found one of the J bolts was just the top inch, there to fool the building inspector. It must have landed under a stud, so they cut it off, and drilled a hole next to the stud, put a washer and nut on, and dropped it into the hole they drilled.

I do like the post-pour fasteners, however, wonder how long the concrete has to cure before installing either the wedge or screw fasteners. I'm assuming that the drill/epoxy system could be done the day after the forms have been stripped.

None of these things resist uplift unless there is an accompanying strap that ties into preferably a large post built into the wall which is also rigidly strapped to the roof or beam which rafters or trusses are then strapped to. I'm not even a structural engineer and I know that much. Uplift forces are resisted by hurricane straps which distribute the enormous overturning forces across dozens of nails in shear. They are usually, if installed correctly, integrated with rebar to distribute the forces throughout the foundation. These anchors are primarily meant to counteract sheer forces and keep the house in place on the foundation. Not to prevent it from lifting up, because honestly, if you don't have hurricane straps, the only thing keeping your house bolted to the floor is the 1.5 inches of 4 or 6 o.c. spaced nails along the bottom of your outer shear, whether OSB, ply, or that nifty zip stuff. Come on, man. Even I know this stuff.

What size thread anchor bolt do you use ? Length and diameter?

I’ve been building medium and high end houses for 30 years and do my own foundation work. I’ve never even remotely had a problem with “j”. Bolts even in Alaska’s seismic conditions. I used 12x5/8 bolts 4 ft. O.C. As far as proper placement use a reusable plastic support that allows proper height and edge distance and you can float under them too.

Just wanted to say thank you! I love creators like yourself who can help most of us see past the "what's good enough; it's been done that way for ages" to understand why other options may be better.

My common sense indicates that an L bolt has a more secure connection than does some screw. But a test showing what is the maximum resistance to pull out is needed. And I wonder if L bolts ever pull out instead of ripping through the concrete?

Subscribed! I’m sure gonna look through your stuff. At the moment I’m trying to find out which Simpson post-framing anchor bolt is needed to be equivalent to or better for hold down than a 1/2” J bolt with a 7” embedment.

you switched from calling out the L anchors for not having enough uplift resistence, to alternatives that are easier to install (good) but also don't have definitively better uplift resistence. what anchoring methods resist net uplift best?

How long after pouring before you can drill and install a Tapcon?

Any anchor will do a great job holding the sill plate down no matter how much lifting force is applied to the structure. The problem is that every part of the structure that is not securely attached to each other with anything but nails can be pulled off of the sill plate. So the studs need some sort of fastener to tie it to the sill plate and top plate and the rafters need some sort of fastener to tie it to the top plates and the roof deck needs some sort of fastener to tie it to the rafters. Otherwise your entire house could be lifted off the foundation except for the sill plate.

Always hooked "J " bolts under the rebar. How would any thing just pushed into wet concrete have any holding power??? Tim

Structural novoice here. Question, wouldn't it be great to make U bolts? Even better if get them go under horizontal rebars during concrete pouring?

I am BEYOND highly skeptical that any of the alternatives presented have greater pull out resistance than a J bolt. Especially now that 5/8" have become the standard in stead of the 1/2".

If you’re a contractor and work in the field, J and L volts are essential. They’re for more than just what you’re saying. Bricklayers use a form of J and L bolts when tying brick into the side of the house. This is the difference between actually doing the job and thinking about doing the job. I was a construction steamfitting and electric for years. I saw the “plans” of engineers and designers. Most of the time, I saw what they said and laughed. For example, an engineer once had an outlet in the middle of where a double door was supposed to be. Now, I’m no engineer, but I think having an outlet in the middle of a double door is unnecessary and potentially deadly. I chose to ignore the plans and did not put an outlet in the middle of a double door. (We’re talking 3 foot from there floor. Another time I had an engineer try to tell me that a 351 Cleveland and a 351 Modified Windsor didn’t use the same engine block. I’m no expert, but I think the only difference is how the timing worked in the engines. I could also be wrong but I believe the only 351 engine block that was distant is the Windsor model. They didn’t recess turn timing chain. Other than that, as far as the blocks, they’re per much the same. But, I’m no engineer, so I could be wrong. I’m 52 years old. I’ve seen “new” ideas come and go. I understand it’s to “secure” Society, but it also creates an undue burden. First, J and L bolts are easier to put in when they concrete is wet, and if you know what your doing you can get a whole city block done in a day. Yes, these “other products” appear great. I understand the physics behind these ideas. I recommend the expansion bolts if the concrete is already hard. I trust it because of vote it’s designed. The screws are pretty tame. I wouldn’t recommend either of them under any circumstances with expansion bolts are just as cost effective. Engineers and designers are great. They’re needed to help guide us. They shouldn’t be the last voice you hear from, though. Talk to people that actually work with these products. I worked with them until I started driving Truck to make more money.