Carriage bolts do not require and should not have a washer at the head end. The head is designed with a square shank so that it burys in the wood and does not rotate. A washer defeats that . Washer is only used on the threaded end under the nut.
1/2" bolt has ~7000 lbs of sheer strength x 2 = 14k lbs at each post in this 'wrong' example. The 6x6 post itself has about the same /compression/ strength. The real reason for the rabbit joint is wood shrinkage. Over time, the treated lumber will shrink and a bolt will loosen. With the beam directly supported by the meat of the post, loose bolts from shrinkage do not compromise the integrity, and can and SHOULD be checked to be tightened.
The beam will have a lower bearing capacity if it’s only bolted vrs sitting on the notch (The shear failure of splitting the beam is lower than crushing it). So he’s not completely wrong, but the problem is the wood and not the bolts (dependent on type of bolts used)
DUUUDE! So glad to see you here. I've been a fan for years of Decks, Docks, & Gazebos. You're quite a crafty guy & seem to really enjoy what you're doing, especially the making people happy part. I'm not keen on notching posts but I see your point. I hope you're still around, making things happen.
After showing this video to a structural engineer, & an architect, and speaking to friends and family who've built many decks in their years, I concluded that duct tape is the best choice.
After 30 years in business, in Tenn if you notch a post your asking to introduce water into the heart of the post which will then freeze and thaw and make the post split over time. Regardless of whatever type of "waterproofing" you add it let the post come apart faster then carriage bolts or lag bolts. I recently repainted a deck i built 25 years ago using lag bolts, stil good and sturdy and straight. I repaired a 10 year old deck another person built with notched posts that was already showing serious degradation to the posts. Decks were built for years and years without notching posts. Unless building codes demand it, dont do it.
Exactly! Just level it, screw it in place, then bolt it together. 1/2" carriage bolts are not going to fail. Water will get you every time, though, if you don't let it drain.
At the corners or our second-story deck where the two courses of double rim joists meet at a 90 are are set on a single notched 6x6 post, which is notched on both outer edges to hold the two courses of double boundary joists. This L-shaped notch leaves a 3x3 section of the beam on the inside corner of the 6x6 and the joists resting on the notches. All secured with nails and no straps or ties of any kind. I'd like to run some ThruLoks through the joists into the post for additional support but only that 3x3 secion of the beams remains as backing for ThruLoks that would need to pass through it from both sections of joists.
1st time I saw this channel... mind blown by how he went straight to the point, and delivered great information that was well explained without making me feel like I was missing out on life while he talked. Well done!! Subscribed, and look forward to checking out the other vids.
Although I like notching, the shear strength of a grade 2 carriage bolt is 13,500 lbs and grade 5 is almost double at 24,400 lbs. The strength of the bolts is well in excess of the lumbers ability to hold an extreme load. The biggest danger is the lumber could split at the bolts when places under excessive loads.
there's more than one way to skin a fox. .. but the right way is the way that is still holding years after the check has cleared. I'm a big fan of the notch method. you can't argue with this point load strength. However, I did notice a valid argument of cutting the notch 1/2" shallow to accommodate for shrinkage. thanks for the vid. I probably would have run the lag screws prematurely!
I've been a carpenter for 48yrs. All the comments here about the strength of carriage bolts is correct. Unfortunately this guy stressed (pardon the pun) the wrong point, namely that too much load here, and it would be the beam that would give out first. It would split around the load point on the bolt.
yep, I once built a small water tank stand and greatly understimated the load. It was built in this style with large screws suitable for treated pine. Failed around the screws with wood splitting exactly as you describe. Seeing it was all in place i used some heavy duty supports brackets (angle iron) and thru bolts. Been sitting there for 8 years now and still seems happy. Lesson learnt.
I think your comment is the most informative here. It explains the reasoning behind the video's message better than the video lol. I wonder if there is a way to get drainage/airflow with a system like this to prevent long term rot between the 3 peices of lumber?
What he is showing is how they used to attach the beams on decks. If you have been a carpenter for 48 years you already know that. They never notched the post back then and even in the 80's.
I am an engineer. I know what shear is. Those bolts are in double shear. They get to add strength. The area of a 1/2" bolt is 0.2 sq inches. The cheapest steel is good for over 100 ksi. So 20,000 pounds per bolt shear, but double shear is 40,000 pounds per bolt. Two bolt s 80,000 pounds. That is 5 big elephants. More elephants of average size. When he breaks off the screw, he loading a cantilever. That is not shear.
even five 16 penny nails will take over 800LB before they will shear? With that said I do exactly as the video described notch out and then I nail them in place.
@Clark Magnuson, I understand where you're coming from, but you left out the possibility of wood failure as the cause of a deck collapsing. Shear value is meaningless and has no effect in that situation. Why take a chance on just a bolt to hold up a support beam?
Bolted joints work by creating friction between the two surfaces, therefore if the bolts are tightened sufficiently all the shear load is taken by the wood. The “wrong way” is fine assuming the bolts never come loose. When they do (most likely by the wood shrinking/relaxing under the compression from the bolts) then the wood will shift and load the bolts in shear. The failure point will then likely become blowing the bolts out the top side of the beams. The “right way” is safety in the long run as it doent matter how tight the bolts are as long as they stop the beam falling off the post. Also, carriage bolts shouldn’t have washers, they have a square protruding under the head that’s intended to stop them spinning. The washer will reduce or prevent the protrusion engaging with the wood making it likely impossible to tighten fully.
@@gregoryclifft7398 gotta agree with u timber shrinks across the grain especially wet treated timber as it dries incorporating a shoulder in to the post for the beam to sit upon is definitely the way build heavy load bearing floors
Hi there, so my deck is done exactly like your example going back to 1995. Thus being 25 years old still in great condition. 6x6 posts while using 2x10 sandwich with gal. Bolts with washers. But want to make it right. I believe I can notch the inside of the 6x6 1.5” and put back the 2x10. Would that be a good enough fix? Cheers..... Yvon.
When you cut the pressure-treated do you need to re-coated copper Green or some other type of sealer, I’m in California and we just use beams on top of the post with a bracket between.
Normally the bolts won't see much in shear due to the friction the bolts are providing between the two wood pieces. The problem occurs when the bolts loosen up and start taking the load directly. Even so, the typical homeowner's deck doesn't carry huge amounts of weight (except maybe when piled with snow) and one carriage bolt in a deck would never be a single point of failure. That being said, best to build to code.
I would always notch out but for smaller decks would use the carriage bolts and use a 2x4 support underneath the load for additional support. There is a few ways to skin a cat as long as your not breaking code
@@daviddou1408 Designed for use with square-neck bolts such as carriage bolts, these washers have teeth that dig into wood and other soft material to prevent rotation.
Maybe speed is important if you make lots of structures, but for a DIY that does this a couple of times in a lifetime, what's a few extra minutes? I would like to know which one is better? Lag screws or carriage bolts? I would still choose carriage bolts because they "compress" the wood and add friction while the lag screws "pull" the wood to add friction.
If notched method, best to notch both sides for a beam on either side, by putting both together you dont allow air to dry out when they get wet. Have seen many of these needing replaced because the rot between them from always holding moisture
It was pretty much what I was expecting to see for exactly that reason. I'd have thought it would be better to allow free air flow to around as much of the structural timber as is possible. And particularly so where said structure is potentially going to be out of sight or difficult to access in future.
Working on a plan where I ran into this issue. Would there be any way around notching to instead run a long enough 2x(post width) fastened and glued underneath the beam to help carry the load?
Hey Jason, doesn't the friction from tightening the bolts carry the load, not the shear stress of the carriage bolts? I do appreciate the notched version also.
That's a good question! But, what happens if the wood shrinks as it dries. No more tension, no more friction. Then the bolt is loaded in shear. Soooo...I would say no! Technically, the joint would be statically indeterminate. Because we don't know how much of the load is carried by friction and how much by shear. Although, we usually assume friction less joints in statics.
@@markflierl1624 .......wood shrinkage compromising a friction grip is a good point and the sort of detail I'd consider these days . As a teenager I built a big tall shed by bolting all the timber together. I thought ten years would be good lifetime for it. Sold the property thirty years later with the illegally built shed still sitting firm..The Australian eucalyptus timber was dry and the environment was high humidity leading most likely to timber swelling slightly.. I had to use bolts and drilling cos it's impossible to hammer nails into the dry timber. The timber shown in this video doesn't look like serious construction timber to my eyes.
@@markflierl1624 Firstly,some of the wood pinched between the bolt and nut is crushed so cannot shrink any further. Secondly there is nothing to stop you re-tightening the bolts after say 2 years. Thirdly never rely on fixings alone because then you are one timber /fixing defect away from structural failure. Even a 1/2" notch will impart incredible additional strength to the structure.
In theory the washer is smart since you don't need a real bite on the wood and it will create less splitting pressure. It just need to hold it in place right?
@@colbornfarms4849 i agree. But at the same time there is no harm by it being part of this particular system.."might" actually have benefits of holding it in place with a bigger head surface
thank you, 20 years ago we bud my deck, and the post beam is installed exactly as you presented the wrong way. There are Six 4/4 scattered beams, I am noticing some crack in the beams. Should I place few more 6/6 next to the other beams? How can I reinforce it? I can not effort to ripped all down. Thanks
It's not actually in shear. The bolt provides clamping force which creates friction resistance. This is how a lug nut/stud works. They are only in tension. Anyone who's had a lug nut come loose knows the wheel comes flying off very quickly after that. That said wood is not like metal, it will wear in and that clamping force will decrease. The problem then isn't sheer force it's pull out force. Think of how little that carriage bolt head is. The entire force is being placed on that. That's why all thread with washers on both sides is better. Even then the way he shows is good insurance. It's only better to use hangers and not cut out a bunch of wood. He's effectively creating stress concentrations and putting shearing force on wood grain. That's a bad idea.
Wow. Yes, the carriage bolts are stronger than the wood will ever be. Yes the method shown is better. Yes, the 'wrong' way will last for many decades. Yes, the bolts are in shear though there are tensile forces also acting on it. That said, the 'right' way will not sag relative to the post, and will not cause a lump in your floor. The 'wrong' ways point of failure will either be the horizontal grains in the wood splitting or the lumber deteriorating.
@@mjones2431 Something can be said for spreading out the load over a larger area on the supporting post. Green lumber can shrink placing the load on the bolt which is only a fraction of the area resting the weight on the top. Much depends on the load it is expected to carry.
Yeah. A 3/8 bolt would take a shit ton to shear. I guess if you are putting a hot tub or have a deck 30foot off the ground, notch it. If the only load on the joist is the deck boards and people, 2 3/8 bolts will out last the wood.
The carriage bolts could be fine in that configuration, as long as one respects the ratings of the bolt. But then again, I think resting the beam on the post is better because over time, if the carriage bolt rusts and weakens, the safety won't be compromised as quickly.
It's simply code to not hang beams off of bolts. The safe shear strength of those bolts is over 1,000 lbs each but then that assumes that the wood never fails with the point load. It will rarely be a problem, and for a deck a few feet off the ground, who cares but the inspector......but you'll care plenty if someone has the authority to say you have to redo everything properly.
What are you talking about ... "no shear strength"? Those two 5/8" carriage bolts have a MINIMUM shear strength of 73, 300 lbs ... 36 TONS, which far exceeds the shear strength of the lumber! Now, I cut shoulders in my post, but I do it for the right reasons. [Most inspectors will fail an unshouldered joint not knowing why.]
It's the wood that fractures, not the bolt. I've seen it. Another problem is splitting the beams around the post. The 2 beams gain strength by sandwiching them together!! Its ridiculous to divide the beams apart. You lose the whole purpose of the beam!!
@@markherman4023I hear what youre saying but thats due more to improper technique. If they're dried and flashed properly they dont get rotten in between and they are stronger together than they are seperate.
What's the sheer strength of the board when it splits across its grain. The joint is shouldered because its stacked on framing, this is the same reason we dont build ballon framed houses anymore. The bolt may be strong but the wood is not.
Someone already mentioned this, but I would think the problem with the first configuration is that the beam will crack horizontally long the grain and in line with the bolts way before the bolts shear. I like your solution just fine.
Hi there... I have a deck (24’ l x 12’ w & 8’ h supported on 4 - 6x6 ) exactly as your example. It’s in great shape even though it’s was build in 1993. No signs of rot to justify replacing parts. Any fix or improvement suggestions? Cheers..... Y.
Now, I'm just a 30 year in the trade electrician with my state contractor's licence C10 with 16 years as a commercial industrial journeyman in the IBEW. I don't know a lot about framing except that I have to bore holes through it and notch it sometimes. But, doesn't using a carriage bolt and putting a washer on the head end defeat part of the purpose of the design of the carriage bolt? Meaning the square portion under the head of the bolt is there to counter sink into the wood to keep it from spinning and to help it bite when tightened? I may be wrong but, that was always my thought.
@@jmjn916 ---- a lock washer keeps the nut from loosening and backing itself off the bolt that's a lock washer's function. Same with a locking nut with the acorn shape and the nylon plastic inside on the threads. Both keep the nut from backing off. The main point of a carriage bolt is to have the tamperproof head with the square on the underside of the head to sink into the wood when tightening the nut on the carriage bolt.
ok, am a 30 + yr experienced carpenter/builder on an island ,in a resort town with a boat building industry and of alot upper end homes where quality, code are a must, we are in a hurricane zone. Many VERY GOOD wood workers, shipwrights, joiners, carpenters, cabinet makers here. Cudos to you, very few carpentry videos on TH-cam impress me... BUT FINALLY some one doing it right..... great job
Oh Mark you said it perfectly, alas, from all the posts, you need to go off on a 15 paragraph tangent, then they'll listen 😉 And say you have degrees and diplomas and diplomatic immunity, dont say engineer tho, seems they're not well thought of 🤣😂🤣😂🤣
I am using 16 foot 6x6s to support a deck, then add a shed roof over the deck. The 6x6s will be put on Armstrong brackets bolted to concrete pillars. Should I notch out to support the perimeter joist? Will notching the 6x6 remove strength to support the roof above?
Glue and nail the joists together, then place the beam on top of the post and put 45 degree 4x4 braces. Fasten with strong ties. No bolts or notches needed.
Funny, all the decks I've seen like this, I've had to repair due to water damage or dry rot in the area you cut out. Great place for water to settle in.
@Brian Van Horne would just end up rotting your beam prematurely. Just use a post saddle on top of a post and sit your beam on top, besides a double beam doesnt pass code here, has to be a triple and either would using deck screws either
This is what I only ever used to use concrete stumps. The bearer sits on top threaded through the steel out of the stump itself. I’d still rather see a deck built with the bearer notched in that putting the whole load weight on the shear strength of the coach bolts
Yikes ....I did it the incorrect way in 1994 ,but on 4x4’s @ 6’ centre’s ,length and width but my deck is the only one in the neighborhood that is still all original and is in great shape still. Should I or could I strengthen this up somehow?
While I don't necessairly agree with his method, they do make washer with square holes for carriage bolts, they have points on them that grip into the wood so it will not spin on you if you need to take the off
Good info. How would you lower the front edge of a deck that has raised at the front due to maybe the footings raising over time. This has caused the deck to be lower at my cottage and higher on the outside edge.
I've seen a lot of people argue for notching. I just don't buy it. I understand the argument that carriage bolts are designed for shear strength, but they never seem to address the fact that there are usually two carriage bolts at each post and they are really thick. It would take a tremendous force to shear both of them simultaneously. Also, they are under constant tension - they're basically squeezing the post which means you would have to overcome that friction as well. Not to mention how the joists are connected to all the other framing members including the decking material. Just seems like bs to me.
Quite a revelation that the shear strength of steel goes to zero when used in carriage bolts. A lot of structures around the world are going to collapse.
Any structure that relies on the shear strength of any fastener deserves to collapse. Please provide the blue prints the the structure you say relies on the shear strength of any fastener.
@@logicalspartan carriage bolts don't rely purely on shear strength however. It's a combined factor between the compressive strength, shear strength, and the nails you always also add. The video is literally saying 1/2 carriage bolts have no shear strength, and that's grossly incorrect.
@@logicalspartan As a structural engineer, I've designed quite a few structures with only bolt shear. The steel manual gives two ways to design with bolts: using bolt shear and using friction. They even go so far as to show a difference between bolt threads in the shear plane or the bolt shank in the shear plane. The Aluminum Association manual doesn't even show friction connections, because aluminum doesn't work that way. And yes, quite a few people design entire structures out of aluminum.
You can get stainless carriage bolts. So let’s drop the rust issue. The carriage bolt has 33,000 psi shear strength. Using the correct amount and size of bolts. Provides plenty of strength. The wood will rot first and for pressure treated cutting to make the nest is opening it to rot sooner Note I’m getting ready to replace a 32 year old deck. It is the cut edge rot that is necessitating the replacement.
while I agree that either way is probably jusy fine for regular loads, if you load a deck with a hot tub, you definitely have to notch your beams into the posts like the video. Same if you were to have a large number of people.
There is a big problem with that construction that most contractors miss. Wood shrinks along the depth and width dimensions but not really along the length dimension. By having the top of the post flush with the top edge of the beam the post end will end up above the beam edge (after the wood shrinks) and a bulge or crack will appear in the decking laid across the area. To do it correctly the top of the post should be about 1/2" lower than the beam edge to allow for shrink.
Wood, especially wood used outdoors, grows and shrinks seasonally (expands and contracts). Over time it does become more and more stable but it will still "move". To prevent expansion and contraction, from being an issue, I recommend that you always set the beams/joists higher than the top of the posts.
sure, if you got a month, but then it will swell again first rain. What Jason Lake ALSO did wrong is not keeping the post top down from the top of beans about 3/8". If beams shrink post will push deck plank up and that will be a real bitch to correct, and really piss off an owner. MAYBE lumber shown is treated not to shrink but should still hold post down @@vinceking7878
I've been trying to make a loft bed frame and I very rarely see this principle of putting the beams on top of the posts being followed in youtube videos. I don't know if this is required for things like beds that won't hold so much weight, but it seems like a sound principle to follow regardless.
@@chrisburns5691 correct! NOW the bolts only job is to hold the ledgers on to the post, NOT take the load of the deck, the post is taking all the load.
What abt a 6x6 post in the corner where two 2x10’sx12 ‘ will be meeting. I get shaving the one side for load bearing but if i shave the other side of the 6x6 so the corner is flush, will that in your opinion lessen the 6x6’s strength and purpose ?
@@guywalker5205 No, it IS wrong. Its an engineering and Code (lawsuitability) failure. A lot of people luck out and don't get bit, its from the majority of others failures that proved it was a failure which is why it became 'bad practice'.
This makes sense if you've got elephants on your deck, and is a better way to support a beam, but your demonstration of shear on that screw is desperately misleading. You've shown a bending moment, not shear.
No elephants just the dead load that increases with the size of the deck and a live load of people. Also depending on were u live the deck might need to also support several feet of wet snow in the winter.
When you notch the post as the person did you reduce the ability of the post to withstand racking by half. By using the bolts you increase the ability of the post to withstand racking. The shear strength of a 1/2 galvanized carriage bolt is in the realm of 8000lbs. So x2 you looking at 16000lbs per post. The Electric utility industry uses 2 5/8 galv machine bolts to hang a 5000lb regulator and it will withstand cat2 hurricane force winds.
"No shear strength on carriage bolts". WHAT?! Of course there is. They are rated for shear loads! That's why many areas specifically allow, in their code, attaching beams to posts in the way you say is inappropriate. Just because sitting the beam on a shelf in the post is stronger doesn't mean that carriage bolts aren't *strong enough*, and that is the purpose of codes: is it good enough or is it not?
+patty109109 Correct. Bolts have shear strength. In an application like this, I'd also be worried about the bearing strength of the wood, where the bolts would tear out if loaded too heavily and if the bolts themselves do not fail, like what happens with rotten wood. But if the beam sits on the post, that removes the wood's bearing strength from the equation as well.
_"if the bolts themselves do not fail, like what happens with rotten wood."_ A deck made out of rotten wood is unsafe, full stop. Doesn't matter HOW you construct it! Exposed wood will tend to weather, warp, crack and rot over its lifetime, and periodic inspection and maintenance is mandatory. *A deck is NOT "set and forget," and there is no need for the carriage bolts to be, either.*
John Dough if you're worried about the strength of the wood, use better wood, or a thicker beam, or place the bolts a bit lower on the beam, or use a timber-jointing plate as used for nailed roof trusses. Better not to cut into the timber and expose untreated wood and create surfaces to collect damp and standing water.
As far as the skill saw issue, SKIL was the first company to make a widely used citcular saw AND in the US the name SKIL became a generic name for this type of saw. My dad called them skil saws and I still do.
@@chrisburns5691 To be fair, it probably depends on application. Those carriage bolts looked to be about 1/2" and combined would have significant strength. This is the wood equivalent of a rivet. Now if you have a large deck that needs to support thousands of pounds, not the best way. Small deck designed to hold 4-8 people, probably just fine. Also, I don't like notching the 6x6 on the side. Now the load is only put on one half of the post. Furthermore, there are better attachment options out there.
@@SpaceMonkey2385 i agree that they would be strong enough, my point is that they wouldn't pass code. My preferred method when I've built decks in the past is to rest beams on top of posts, and attach with appropriate hardware. Notching is better than just the carriage bolts, as the point load is transferred directly to the solid bearing of the 6x6. Still I prefer resting the beam on top, when I've built decks in the past. As a carpenter I've learned what will pass an inspection and what wouldn't. Supporting a beam off carriage bolts alone would not pass an inspection, at least around here.
@@chrisburns5691 🤣😂😂 it passes code everywhere I’ve ever been. The other way is fine depending on application. Some engineers want it done that way when you set porch posts.
@@DonnyBoy286 interesting, doesn't meet code anywhere ive worked, and definitely not common practice. Typically set beams on posts. Would never fly for a 2nd story structure.
Notching is not allowed by code in the IRC (which most of the U.S. uses). To connect beams to posts, you should use brackets that are specifically designed for the purpose. About $5 at your local hardware store for galvanized (a lot more expensive for stainless, but stainless is necessary in coastal areas).
Simplier to set the beam on TOP of the post and use either a tie metal plate or nail/screw/bolt a 2x6 on either side of the post to build a pocket. 30 years later with treated lumber my deck is still standing !!
I have just calculated the shear strength of a 12mm (1/2") carriage bolt is between 56 and 72 tonnes. That is assuming the moving surfaced do not deform I would be happy to use a 50% value for my structural validations. And there were TWO carriage bolts !! You need a lesson in structural mechanics my friend.
I was just thinking about this issue and this video popped up on my phone. I will try it out and see. Always used carriage bolts and cantilever method. Maybe I can now drive my car up on the deck with my pet elephant. Seriously. Nice having options.
While your method my be code and perhaps a stronger way of construction. I've seen many many decks and never not one single time has the failure of the deck been due to the carriage bolt sheering.Its always rotting wood,splitting wood, or some other reason but never has it been due to failure of the carriage bolt.
But when the wood gets older the pressure on the holes around the bolts may brake and cut through the beam. The method he showed is much more durable but for a different reason.
@@Sauromannen yeah definitely prefer his method. But he was saying basically that the bolt couldn't handle the sheer strength, which ain't really accurate. As you said the timber would probably fail first.
Your correct, it's not that the "carriage bolt" doesn't have sufficient strength to resist shear loads... it's the wood that will fail. Such a statement in court would get you laughed out... such a statement in the work place will get you kicked out.
We like to watch amateur bunglings. People like this came from Mexico and called themselves carpenters. Ruined my wages from the 80s. Journeyman carpenter from First year apprentice in 74. Till i retired 10 years ago. Superintendent for 5 of those years in the early 80s. These people have had no real training.
@@jerrynewberry2823 your so right. Very few companies train anyone nowadays. No time. Not enough profit. Overhead is to high. Yet a 500,000$ house only cost under 200,000 to build. Wheres all that profit going?
i've never seen a washer used on the head side of a carriage bolt. isn't the little square part supposed to grip into the wood to keep it from turning when being tightened?
Thats because the shear strength of carriage bolts are incredibly high.. The wood around the bolt would start failing before the bolt does. You could always go around under the deck and shore up some wood under the joist and tie it into the post if there is any sagging etc or wood failure.
@@RSoles-hz9nc The trouble I have seen with through-bolts is that they invariably loosen up causing the post and joist to drift out of square, not to mention that where I live inspectors would fail them every time. The ones I see are usually on homeowner or brother-in-law decks that were never permitted. Are you making sure your layout is square, and do you use a plumb line to determine pier location before locating and measuring the posts? That is how I do it and although it is not perfect (what is?) it always gets me to within about half an inch or so for the post location which is close enough for the pier, then I measure the location for the notches after determining exactly where the rim joists will be located. I also use scrap lumber to do a mock-up especially for larger decks and that helps. I'm not trying to insult your intelligence, just trying to be helpful.
I'm going to be building a porch into my trailer and it's going over a concrete pad and I can dig holes to set the post because of city sewer line and gas lines, but I thought I saw where there bases I can secure to the concrete to set and hold my post into place and was wondering what they are called and what would be the best kind to get and how to put the secure screws in the proper way for maximum safety.
I wonder if he first tried to break one of those carriage bolts. Can you imagine how much force that would take? The wood would fail far before the bolt shears
@@RichardMiller-tq6ut around 5000lbs shear strength on 3/8" carriage bolts. So with 2, you're looking at 7500lbs-10,000lbs of weight you can put on that beam before it might snap. So unless you're planning to drive a big truck over your deck, it's probably fine.
Question....what do w e do with post and beam timber framing? No bolts, no nails, mostly just tight fitting wood connections with wooden pegs. Now, the old barn still standing built by farmers, not one of them an engineer. Snow comes...3 ft deep on the roof, then it rains and the snow holds the addition water weight ...for a while. Maybe even 20 or so blizzards later, with 4 or 5 with following rain. Will the barn still be standing ? I bet it will. They are still standing and still in use. BUT...our steel boat storage shed , in Lake George NY collapsed in about ‘79 or ‘80. The storm dumped 3 ft of snow on the almost flat roof, then it rained. Several 30 plus length cruisers were inside. A number of boats were Totaled. The solution....put a snow blower on the roof and blow the snow before the rain. If you can’t, build another boat storage building. OR maybe get a bunch of Amish to build you a big boat barn. Timber framed of course . I am agraduate Civil Engineer and served on the national building code for elevators in my career. Our goal as having standards establishes for public safety was to do the best we could to protect the public without breaking the financial back of the owners and contractors while insuring long service. It is possible to build a deck that would still be intact after the tornados, blizzards and fires passed. Nobody would buy one. It would be ugly. Hire the farmers to build your decks. Problem solved. Bless you all. JoeB
I built mine 12 years ago the wrong way, with just wood screws and it hasn't moved an inch... then again I don't need a deck strong enough to park a car on either.
Span of a double 2x6 beam is limited to about 6', so each post would have about 36 square feet of deck it's supporting. Deck loading is typically estimated at between 50 lbs and 100 lbs / square foot (higher in some locales). Deck load on each post would then be between 1,800 - 3,600 lbs. Load capacity of the 6x6 post is 20,000 lbs. Standard deck footing on clay soil is load capable of about 5,000 lbs per square foot. Most guys put a 12" circular concrete footing under each post, or about 0.8 square feet. So the footing would be rated at 4,000 lbs. Shear strength of even cheap 1/2" carriage bolts exceeds 10,000 lbs, and there are two in the beam, for a minimum capacity of 20,000 lbs, typically closer to 40,000 lbs. Results: the concrete footing in clay soil exceeds capacity estimates of the deck by just +10%. The 6x6 post exceeds capacity needs by +300%. The carriage bolts have a safety margin of between +300% and +700%. The doubled 2x6 beam is right at capacity in this "design," and is the weakest point. Expert advice would be to increase the beam to doubled 2x8. Notching the posts adds some strength, but only to parts that are already the strongest part of the deck in this video.
What about all four corners of a deck? This method seems practical for a single beam, but the deck I’m build, for example, is detached from any structure and will also be supporting a hip roof. I was going to make my own box beams and go all the way around and just use carriage bolts to secure them but now I’m second guessing. My posts are 6x6...run joists 2x10....deck will be 12x12. Any suggestions?
Carriage bolts do not require and should not have a washer at the head end. The head is designed with a square shank so that it burys in the wood and does not rotate. A washer defeats that . Washer is only used on the threaded end under the nut.
That makes sense. Do you like the technique in the video ?
1/2" bolt has ~7000 lbs of sheer strength x 2 = 14k lbs at each post in this 'wrong' example. The 6x6 post itself has about the same /compression/ strength. The real reason for the rabbit joint is wood shrinkage. Over time, the treated lumber will shrink and a bolt will loosen. With the beam directly supported by the meat of the post, loose bolts from shrinkage do not compromise the integrity, and can and SHOULD be checked to be tightened.
LOL, spot on.
The beam will have a lower bearing capacity if it’s only bolted vrs sitting on the notch (The shear failure of splitting the beam is lower than crushing it). So he’s not completely wrong, but the problem is the wood and not the bolts (dependent on type of bolts used)
DUUUDE! So glad to see you here. I've been a fan for years of Decks, Docks, & Gazebos. You're quite a crafty guy & seem to really enjoy what you're doing, especially the making people happy part. I'm not keen on notching posts but I see your point.
I hope you're still around, making things happen.
After showing this video to a structural engineer, & an architect, and speaking to friends and family who've built many decks in their years, I concluded that duct tape is the best choice.
I agree . edited double sticky tape .
And using the right color blends in. 😆🪄
I'm all about the velcro
yes, but triple wrapped! And lets be real, the pros are using tuck tape, for those wet environments!
I'm thinking tie wraps.
After 30 years in business, in Tenn if you notch a post your asking to introduce water into the heart of the post which will then freeze and thaw and make the post split over time. Regardless of whatever type of "waterproofing" you add it let the post come apart faster then carriage bolts or lag bolts. I recently repainted a deck i built 25 years ago using lag bolts, stil good and sturdy and straight. I repaired a 10 year old deck another person built with notched posts that was already showing serious degradation to the posts. Decks were built for years and years without notching posts. Unless building codes demand it, dont do it.
Exactly! Just level it, screw it in place, then bolt it together. 1/2" carriage bolts are not going to fail. Water will get you every time, though, if you don't let it drain.
Even better is to laminate 2 boards together into a solid beam and install directly over the post. No notching. No lag bolts needed. More strength.
@@JM-nh8yp This is the way 👍
Great example. Thanks for sharing!
What would be the best approach for 2 beams that meet at a corner post?
Thanks again.
At the corners or our second-story deck where the two courses of double rim joists meet at a 90 are are set on a single notched 6x6 post, which is notched on both outer edges to hold the two courses of double boundary joists. This L-shaped notch leaves a 3x3 section of the beam on the inside corner of the 6x6 and the joists resting on the notches. All secured with nails and no straps or ties of any kind. I'd like to run some ThruLoks through the joists into the post for additional support but only that 3x3 secion of the beams remains as backing for ThruLoks that would need to pass through it from both sections of joists.
1st time I saw this channel... mind blown by how he went straight to the point, and delivered great information that was well explained without making me feel like I was missing out on life while he talked. Well done!! Subscribed, and look forward to checking out the other vids.
As
Always nice to have a supportive daddy.
Thats why I use solid Iron lumber with wooden screws.
Saxophone Edifier this is one of the most hilarious comments I’ve ever heard , lol & thanks for posting , made my day
I’d hit like a dozen times if I could .. really funny comment man 😀
You win! :-)
Brilliant!
😂nice!
I normally use double sided sticky tape
Ha ha ha!
I just chew lots of bubble gum while building and pluck pieces straight outa my mouth as needed to fasten things🤗
As long as it's 3M, and not some cheap knockoff, you should be good.
@@lonefeather49 by the time the gum dries out, the bugs should be holding hands
I use silent Velcro, just in case I change my mind halfway through the project!
Although I like notching, the shear strength of a grade 2 carriage bolt is 13,500 lbs and grade 5 is almost double at 24,400 lbs. The strength of the bolts is well in excess of the lumbers ability to hold an extreme load. The biggest danger is the lumber could split at the bolts when places under excessive loads.
And when the wood splits, all that sheer strength means nothing.
there's more than one way to skin a fox. .. but the right way is the way that is still holding years after the check has cleared. I'm a big fan of the notch method. you can't argue with this point load strength. However, I did notice a valid argument of cutting the notch 1/2" shallow to accommodate for shrinkage.
thanks for the vid. I probably would have run the lag screws prematurely!
I am assuming I could do the same with a round post made up of 6-8" PT. Am building a base for a sawmill to sit on. Thoughts?
All you easy chair experts here are a hoot, this guy is correct. Other ways will work, but his way provides for the maximum support.
This guy is not correct ! if he said there is a better way that would be correct
try telling that to our local building inspector !!!! He has no trade qualifications but read a book and wrote a test !
I've been a carpenter for 48yrs. All the comments here about the strength of carriage bolts is correct. Unfortunately this guy stressed (pardon the pun) the wrong point, namely that too much load here, and it would be the beam that would give out first. It would split around the load point on the bolt.
yep, I once built a small water tank stand and greatly understimated the load. It was built in this style with large screws suitable for treated pine. Failed around the screws with wood splitting exactly as you describe. Seeing it was all in place i used some heavy duty supports brackets (angle iron) and thru bolts. Been sitting there for 8 years now and still seems happy. Lesson learnt.
I think your comment is the most informative here. It explains the reasoning behind the video's message better than the video lol. I wonder if there is a way to get drainage/airflow with a system like this to prevent long term rot between the 3 peices of lumber?
What he is showing is how they used to attach the beams on decks. If you have been a carpenter for 48 years you already know that. They never notched the post back then and even in the 80's.
You are right.
Can you use the same notch detail for both the first story deck beam and a second story deck beam using the same 6x6 post if it's 2 stories tall?
I am an engineer. I know what shear is. Those bolts are in double shear. They get to add strength. The area of a 1/2" bolt is 0.2 sq inches. The cheapest steel is good for over 100 ksi. So 20,000 pounds per bolt shear, but double shear is 40,000 pounds per bolt. Two bolt s 80,000 pounds. That is 5 big elephants. More elephants of average size.
When he breaks off the screw, he loading a cantilever. That is not shear.
even five 16 penny nails will take over 800LB before they will shear? With that said I do exactly as the video described notch out and then I nail them in place.
Clark Magnuson succinctly put mate 👏👏👏
T
Analog human - would recommend the concrete patio...with that gathering, weight will be last of your cleanup worries...
@Clark Magnuson, I understand where you're coming from, but you left out the possibility of wood failure as the cause of a deck collapsing. Shear value is meaningless and has no effect in that situation. Why take a chance on just a bolt to hold up a support beam?
Bolted joints work by creating friction between the two surfaces, therefore if the bolts are tightened sufficiently all the shear load is taken by the wood. The “wrong way” is fine assuming the bolts never come loose. When they do (most likely by the wood shrinking/relaxing under the compression from the bolts) then the wood will shift and load the bolts in shear. The failure point will then likely become blowing the bolts out the top side of the beams. The “right way” is safety in the long run as it doent matter how tight the bolts are as long as they stop the beam falling off the post.
Also, carriage bolts shouldn’t have washers, they have a square protruding under the head that’s intended to stop them spinning. The washer will reduce or prevent the protrusion engaging with the wood making it likely impossible to tighten fully.
So the question is, do you use a washer on the nut side?
Never count on friction for carrying load.
@@gregoryclifft7398 gotta agree with u timber shrinks across the grain especially wet treated timber as it dries incorporating a shoulder in to the post for the beam to sit upon is definitely the way build heavy load bearing floors
Absolutly yes, you use a washer on the nut side, not the head side.
@@blaster-zy7xx there’s wrong ways and Right ways to build
Hi there, so my deck is done exactly like your example going back to 1995. Thus being 25 years old still in great condition.
6x6 posts while using 2x10 sandwich with gal. Bolts with washers.
But want to make it right.
I believe I can notch the inside of the 6x6 1.5” and put back the 2x10.
Would that be a good enough fix?
Cheers..... Yvon.
When you cut the pressure-treated do you need to re-coated copper Green or some other type of sealer, I’m in California and we just use beams on top of the post with a bracket between.
Normally the bolts won't see much in shear due to the friction the bolts are providing between the two wood pieces. The problem occurs when the bolts loosen up and start taking the load directly. Even so, the typical homeowner's deck doesn't carry huge amounts of weight (except maybe when piled with snow) and one carriage bolt in a deck would never be a single point of failure. That being said, best to build to code.
I would always notch out but for smaller decks would use the carriage bolts and use a 2x4 support underneath the load for additional support. There is a few ways to skin a cat as long as your not breaking code
Use a washer and
lock washer on the nut side of the carriage bolt. A carriage bolt is not designed for a washer on the head side of the bolt.
@Les Brown Really? Shrinkage can work in your favor or against you. Should be factored in.
Torque Washers for Carriage Bolts.
@@daviddou1408 Designed for use with square-neck bolts such as carriage bolts, these washers have teeth that dig into wood and other soft material to prevent rotation.
Just use a hex bolt anyway. Carriage bolts are terrible.
I use wooden bolts in all my deck projects
Cool video! Thank you for posting it! Would you use the same notch in a 4x4 attached to a 2x6? Thank you.
I like the new self taping lag scews that replace the carriage bolts in many applications. So much faster.
Maybe speed is important if you make lots of structures, but for a DIY that does this a couple of times in a lifetime, what's a few extra minutes? I would like to know which one is better? Lag screws or carriage bolts? I would still choose carriage bolts because they "compress" the wood and add friction while the lag screws "pull" the wood to add friction.
If notched method, best to notch both sides for a beam on either side, by putting both together you dont allow air to dry out when they get wet. Have seen many of these needing replaced because the rot between them from always holding moisture
It was pretty much what I was expecting to see for exactly that reason. I'd have thought it would be better to allow free air flow to around as much of the structural timber as is possible. And particularly so where said structure is potentially going to be out of sight or difficult to access in future.
This is absolutely correct.
Having trouble visualizing what you mean? Care to produce a video?
noone n A smaller rabbet on each side rather than one large rabbet on one side of the post.
David Moore many people do not treat the notches with wood preservative and that also leads to early failure
Working on a plan where I ran into this issue.
Would there be any way around notching to instead run a long enough 2x(post width) fastened and glued underneath the beam to help carry the load?
Hey Jason, doesn't the friction from tightening the bolts carry the load, not the shear stress of the carriage bolts? I do appreciate the notched version also.
Yes
That's a good question! But, what happens if the wood shrinks as it dries. No more tension, no more friction. Then the bolt is loaded in shear. Soooo...I would say no! Technically, the joint would be statically indeterminate. Because we don't know how much of the load is carried by friction and how much by shear. Although, we usually assume friction less joints in statics.
@@markflierl1624 .......wood shrinkage compromising a friction grip is a good point and the sort of detail I'd consider these days . As a teenager I built a big tall shed by bolting all the timber together. I thought ten years would be good lifetime for it. Sold the property thirty years later with the illegally built shed still sitting firm..The Australian eucalyptus timber was dry and the environment was high humidity leading most likely to timber swelling slightly.. I had to use bolts and drilling cos it's impossible to hammer nails into the dry timber. The timber shown in this video doesn't look like serious construction timber to my eyes.
@@markflierl1624 I bet you have never seen one Shear off before that's because that theory is just nonsense
@@markflierl1624 Firstly,some of the wood pinched between the bolt and nut is crushed so cannot shrink any further.
Secondly there is nothing to stop you re-tightening the bolts after say 2 years.
Thirdly never rely on fixings alone because then you are one timber /fixing defect away from structural failure. Even a 1/2" notch will impart incredible additional strength to the structure.
Once I saw him use washers under the heads of the bolts I knew instantly he was an internet expert.
I don't know ,did you see how cracked the post was?
@@johnphillips2396 you still don’t use washers on head side of carriage bolts
In theory the washer is smart since you don't need a real bite on the wood and it will create less splitting pressure. It just need to hold it in place right?
@@johnphillips2396 just an example
@@colbornfarms4849 i agree. But at the same time there is no harm by it being part of this particular system.."might" actually have benefits of holding it in place with a bigger head surface
thank you, 20 years ago we bud my deck, and the post beam is installed exactly as you presented the wrong way. There are Six 4/4 scattered beams, I am noticing some crack in the beams. Should I place few more 6/6 next to the other beams? How can I reinforce it? I can not effort to ripped all down. Thanks
If a post (vertical) is cracking, don't worry about it. If a beam (horizontal) is cracking, sister another board making a laminated beam
I enrolled in deck college. I'll let you know when we get to that chapter! 😂
I don't get the imagining a screw is a carriage bolt trick. Do tell
If I wanted to build a lean to roof on my deck what is the best way to
set the posts on the deck or with concrete forms on the ground.
After reading a few dozen of the comments....I'm heading off to the metal yard to get steel posts.
You mean mental yard 😂
Buy yourself a book on carpentry from a country that knows what they are talking about e.g. anywhere in Europe :-)
Those two 1/2 Carriage bolts have more shear strength than that post can structurally hold.
It's not actually in shear. The bolt provides clamping force which creates friction resistance. This is how a lug nut/stud works. They are only in tension. Anyone who's had a lug nut come loose knows the wheel comes flying off very quickly after that. That said wood is not like metal, it will wear in and that clamping force will decrease. The problem then isn't sheer force it's pull out force. Think of how little that carriage bolt head is. The entire force is being placed on that. That's why all thread with washers on both sides is better. Even then the way he shows is good insurance. It's only better to use hangers and not cut out a bunch of wood. He's effectively creating stress concentrations and putting shearing force on wood grain. That's a bad idea.
@@Workerbee94 Correct.. The downward pressure alone would prevent the bolt from being removed.
I have decks over 30 years old done 'the wrong way'. and nothing wrong with them at all..
Wow. Yes, the carriage bolts are stronger than the wood will ever be. Yes the method shown is better. Yes, the 'wrong' way will last for many decades. Yes, the bolts are in shear though there are tensile forces also acting on it.
That said, the 'right' way will not sag relative to the post, and will not cause a lump in your floor. The 'wrong' ways point of failure will either be the horizontal grains in the wood splitting or the lumber deteriorating.
@@mjones2431
Something can be said for spreading out the load over a larger area on the supporting post. Green lumber can shrink placing the load on the bolt which is only a fraction of the area resting the weight on the top. Much depends on the load it is expected to carry.
Would you try to waterproof the exposed part of that wooden column with a piece of flashing or maybe just a waterproof liquid
I wonder if this guy tried to snap off a carriage bolt first with his hammer, and then said screw it, let me get a screw?
Hahaha, I laughed good!
Yeah. A 3/8 bolt would take a shit ton to shear. I guess if you are putting a hot tub or have a deck 30foot off the ground, notch it. If the only load on the joist is the deck boards and people, 2 3/8 bolts will out last the wood.
😂😂😂😂😂😂😂😂😂
The carriage bolts could be fine in that configuration, as long as one respects the ratings of the bolt. But then again, I think resting the beam on the post is better because over time, if the carriage bolt rusts and weakens, the safety won't be compromised as quickly.
It's simply code to not hang beams off of bolts. The safe shear strength of those bolts is over 1,000 lbs each but then that assumes that the wood never fails with the point load. It will rarely be a problem, and for a deck a few feet off the ground, who cares but the inspector......but you'll care plenty if someone has the authority to say you have to redo everything properly.
What are you talking about ... "no shear strength"?
Those two 5/8" carriage bolts have a MINIMUM shear strength of 73, 300 lbs ... 36 TONS, which far exceeds the shear strength of the lumber!
Now, I cut shoulders in my post, but I do it for the right reasons.
[Most inspectors will fail an unshouldered joint not knowing why.]
It's the wood that fractures, not the bolt. I've seen it. Another problem is splitting the beams around the post. The 2 beams gain strength by sandwiching them together!! Its ridiculous to divide the beams apart. You lose the whole purpose of the beam!!
@@JM-nh8yp I never sister treated lumber together espically beams. They will rot twice as fast when sandwiched together.
@@markherman4023I hear what youre saying but thats due more to improper technique. If they're dried and flashed properly they dont get rotten in between and they are stronger together than they are seperate.
What's the sheer strength of the board when it splits across its grain. The joint is shouldered because its stacked on framing, this is the same reason we dont build ballon framed houses anymore. The bolt may be strong but the wood is not.
Wait! What was that u were using to finish cutting the shoulder cut?
Someone already mentioned this, but I would think the problem with the first configuration is that the beam will crack horizontally long the grain and in line with the bolts way before the bolts shear. I like your solution just fine.
the fact that you can snap a screw off with your hammer is not an argument.
He was demonstrating what he meant by shear strength.
The fact that you can post an anonymous comment is not a counter argument
But it is a demonstration of the exact problem.
The codes aren't an argument either. But they are enforceable.
Hi there... I have a deck (24’ l x 12’ w & 8’ h supported on 4 - 6x6 ) exactly as your example. It’s in great shape even though it’s was build in 1993. No signs of rot to justify replacing parts. Any fix or improvement suggestions? Cheers..... Y.
home depot has cheap nail plates. They are twisted to fit the beam and rail, and have held my deck fine for 25 years. I would go with them
Now, I'm just a 30 year in the trade electrician with my state contractor's licence C10 with 16 years as a commercial industrial journeyman in the IBEW.
I don't know a lot about framing except that I have to bore holes through it and notch it sometimes.
But, doesn't using a carriage bolt and putting a washer on the head end defeat part of the purpose of the design of the carriage bolt? Meaning the square portion under the head of the bolt is there to counter sink into the wood to keep it from spinning and to help it bite when tightened?
I may be wrong but, that was always my thought.
Spot on.
Add a lock washer?
@@jmjn916 ---- a lock washer keeps the nut from loosening and backing itself off the bolt that's a lock washer's function. Same with a locking nut with the acorn shape and the nylon plastic inside on the threads. Both keep the nut from backing off. The main point of a carriage bolt is to have the tamperproof head with the square on the underside of the head to sink into the wood when tightening the nut on the carriage bolt.
ok, am a 30 + yr experienced carpenter/builder on an island ,in a resort town with a boat building industry and of alot upper end homes where quality, code are a must, we are in a hurricane zone. Many VERY GOOD wood workers, shipwrights, joiners, carpenters, cabinet makers here.
Cudos to you, very few carpentry videos on TH-cam impress me...
BUT FINALLY some one doing it right.....
great job
On the subject of right and wrong.
Wrong = “there is many ways”
Right = “there are many ways”
I hope you find this helpful.
Here's another one:
"The only way to ....." - always wrong.
Oh Mark you said it perfectly, alas, from all the posts, you need to go off on a 15 paragraph tangent, then they'll listen
😉
And say you have degrees and diplomas and diplomatic immunity, dont say engineer tho, seems they're not well thought of
🤣😂🤣😂🤣
4 years of causing arguments ………… and still going strong!!
HAHA
now 5 years
😂😂😂😂😂
I am using 16 foot 6x6s to support a deck, then add a shed roof over the deck. The 6x6s will be put on Armstrong brackets bolted to concrete pillars. Should I notch out to support the perimeter joist? Will notching the 6x6 remove strength to support the roof above?
Do you typically not use lock washers in addition the regular galvanized washers?
And what would you do with a 4x4? I assume only notching half is better than not at all?
Glue and nail the joists together, then place the beam on top of the post and put 45 degree 4x4 braces. Fasten with strong ties. No bolts or notches needed.
Funny, all the decks I've seen like this, I've had to repair due to water damage or dry rot in the area you cut out. Great place for water to settle in.
I thought that too. Nice place for water to sit and saturate the center of the post
@Brian Van Horne would just end up rotting your beam prematurely. Just use a post saddle on top of a post and sit your beam on top, besides a double beam doesnt pass code here, has to be a triple and either would using deck screws either
I cover the tops of my posts with a sticky membrane like Ice And Water Shield and stain all my cuts.
@@childebrand1 I use redzone and blue skin in certain situations. The best way to keep things dry is just space them out and let air do the work
This is what I only ever used to use concrete stumps. The bearer sits on top threaded through the steel out of the stump itself. I’d still rather see a deck built with the bearer notched in that putting the whole load weight on the shear strength of the coach bolts
Yikes ....I did it the incorrect way in 1994 ,but on 4x4’s @ 6’ centre’s ,length and width but my deck is the only one in the neighborhood that is still all original and is in great shape still.
Should I or could I strengthen this up somehow?
I’m just curious, as to where he found washers, that fit on the head side, of a carriage bolt??
While I don't necessairly agree with his method, they do make washer with square holes for carriage bolts, they have points on them that grip into the wood so it will not spin on you if you need to take the off
It's just a large washer hole... What's the mystery?
Four carriage bolts definitely have some shear strength,especially when held in the wood.
The more bolts you use , the more holes you drill which weakens the wood .
@@stevegagnon9451: Two bolts staggered is optimum and notching is always a bad idea.
I think the concern would be the bearing capacity of the wood, not the shear strength of the bolts.
@@MrMindock well there’s no bearing strength if the ledger plates are bolted to the post
Good info. How would you lower the front edge of a deck that has raised at the front due to maybe the footings raising over time. This has caused the deck to be lower at my cottage and higher on the outside edge.
footings should have been dug to below frost level in ground to prevent this
Well i built my deck the wrong way 24 years ago and still standing strong!🤣🤣🤣
Daniel Primeau I build more than one deck, in earthquake country, and they are all still standing, 15 years later.
I've seen a lot of people argue for notching. I just don't buy it. I understand the argument that carriage bolts are designed for shear strength, but they never seem to address the fact that there are usually two carriage bolts at each post and they are really thick. It would take a tremendous force to shear both of them simultaneously. Also, they are under constant tension - they're basically squeezing the post which means you would have to overcome that friction as well. Not to mention how the joists are connected to all the other framing members including the decking material. Just seems like bs to me.
Well I guess that is you "living life on the edge" - mmm I hope you have a good will and/or lots of insurance!! LOL LOL LOL 🤣😁😜😂
As did I 25 years ago. Still standing. Had a large group over recently. No problem.
@@derikyeager7250You are correct. The odds of 2 carriage bolts shearing are remote if you are using large bolts. Rot and termites are the big hazards.
Quite a revelation that the shear strength of steel goes to zero when used in carriage bolts. A lot of structures around the world are going to collapse.
;)
Any structure that relies on the shear strength of any fastener deserves to collapse. Please provide the blue prints the the structure you say relies on the shear strength of any fastener.
@@logicalspartan carriage bolts don't rely purely on shear strength however. It's a combined factor between the compressive strength, shear strength, and the nails you always also add.
The video is literally saying 1/2 carriage bolts have no shear strength, and that's grossly incorrect.
The bolts are not acceptable by building code and inspectors will flag that. Regardless if they can hold the weight.
@@logicalspartan As a structural engineer, I've designed quite a few structures with only bolt shear. The steel manual gives two ways to design with bolts: using bolt shear and using friction. They even go so far as to show a difference between bolt threads in the shear plane or the bolt shank in the shear plane. The Aluminum Association manual doesn't even show friction connections, because aluminum doesn't work that way. And yes, quite a few people design entire structures out of aluminum.
Very good. Wonder how many build this way ?
A carriage bolt will be intact in 10,000 years when someone says “there was probably a structure here”
Didn't you know , that's what they used to keep the "Great Pyramid" together , right ?
Nope, a brandnew travel bus will be only a stain in the ground after 10.000 years and so will your bolt.
You obviously don’t know the lifespan of galv or the nature of rust ffs 🤦♂️
You can get stainless carriage bolts. So let’s drop the rust issue. The carriage bolt has 33,000 psi shear strength. Using the correct amount and size of bolts. Provides plenty of strength. The wood will rot first and for pressure treated cutting to make the nest is opening it to rot sooner
Note I’m getting ready to replace a 32 year old deck. It is the cut edge rot that is necessitating the replacement.
while I agree that either way is probably jusy fine for regular loads, if you load a deck with a hot tub, you definitely have to notch your beams into the posts like the video. Same if you were to have a large number of people.
There is a big problem with that construction that most contractors miss. Wood shrinks along the depth and width dimensions but not really along the length dimension. By having the top of the post flush with the top edge of the beam the post end will end up above the beam edge (after the wood shrinks) and a bulge or crack will appear in the decking laid across the area. To do it correctly the top of the post should be about 1/2" lower than the beam edge to allow for shrink.
agreed, also if water gets between the sandwiched 2x's it will create moisture that can not dry out, so an air gap would be sufficient
Don H
Can you let it shrink first?
Wood, especially wood used outdoors, grows and shrinks seasonally (expands and contracts). Over time it does become more and more stable but it will still "move". To prevent expansion and contraction, from being an issue, I recommend that you always set the beams/joists higher than the top of the posts.
Thanks for adding that. Most don't realize being a Carpenter (one that gives a shit) is a very technical trade, not just swinging hammers.
sure, if you got a month, but then it will swell again first rain. What Jason Lake ALSO did wrong is not keeping the post top down from the top of beans about 3/8". If beams shrink post will push deck plank up and that will be a real bitch to correct, and really piss off an owner. MAYBE lumber shown is treated not to shrink but should still hold post down @@vinceking7878
When notching, should deck flashing tape be used for moisture?
I've been trying to make a loft bed frame and I very rarely see this principle of putting the beams on top of the posts being followed in youtube videos. I don't know if this is required for things like beds that won't hold so much weight, but it seems like a sound principle to follow regardless.
"Carriage bolts have no shear strength! Let me demonstrate that by using something completely different than a carriage bolt!"
And by applying bending moment rather than shear stress...
did you miss the part where the beam now sits on solid wood, opposed to relying on the bolt completely? lol..
@@chrisburns5691 correct! NOW the bolts only job is to hold the ledgers on to the post, NOT take the load of the deck, the post is taking all the load.
Didn’t you ever learn what an analogy was in school? Whilst it wasn’t a perfect example it did demonstrate his point.
@@bh9275 They do have shear strength though, so it was an inaccurate statement.
What abt a 6x6 post in the corner where two 2x10’sx12 ‘ will be meeting. I get shaving the one side for load bearing but if i shave the other side of the 6x6 so the corner is flush, will that in your opinion lessen the 6x6’s strength and purpose ?
I built my deck 20 years ago using the "wrong" way. It's still absolutely rock solid.
Yep I did the same. This is probably a better way, but the other way isn’t wrong
@@guywalker5205 yes it is you just got away with the wrong way
Doesn't meet code though. That's the reason builders such as myself have to go fix so many wrong diy Jobs.
@@guywalker5205 No, it IS wrong.
Its an engineering and Code (lawsuitability) failure.
A lot of people luck out and don't get bit, its from the majority of others failures that proved it was a failure which is why it became 'bad practice'.
This makes sense if you've got elephants on your deck, and is a better way to support a beam, but your demonstration of shear on that screw is desperately misleading. You've shown a bending moment, not shear.
He is right though, carriage bolts alone do not meet code, and isn't done by anyone doing this work professionally.
No elephants just the dead load that increases with the size of the deck and a live load of people. Also depending on were u live the deck might need to also support several feet of wet snow in the winter.
The previous owners of my house built a deck and used the method you've indicated NOT to use. What way would you recommend for a remedy?
When you notch the post as the person did you reduce the ability of the post to withstand racking by half. By using the bolts you increase the ability of the post to withstand racking. The shear strength of a 1/2 galvanized carriage bolt is in the realm of 8000lbs. So x2 you looking at 16000lbs per post. The Electric utility industry uses 2 5/8 galv machine bolts to hang a 5000lb regulator and it will withstand cat2 hurricane force winds.
Fucking A
Sounds great until you use wood in the real world.
That would be a garbage grade bolt...grade 5 bolt would be over 9000lbs force in shear...at the thread root. Higher on the shank portion.
@@johngoodell2775 What the hell does that even mean??
@@Gippetos Grade 5, 1/2" hot dip galv carridge bolt proof load is 7800lbs
"No shear strength on carriage bolts".
WHAT?! Of course there is. They are rated for shear loads! That's why many areas specifically allow, in their code, attaching beams to posts in the way you say is inappropriate. Just because sitting the beam on a shelf in the post is stronger doesn't mean that carriage bolts aren't *strong enough*, and that is the purpose of codes: is it good enough or is it not?
+patty109109 Correct. Bolts have shear strength. In an application like this, I'd also be worried about the bearing strength of the wood, where the bolts would tear out if loaded too heavily and if the bolts themselves do not fail, like what happens with rotten wood. But if the beam sits on the post, that removes the wood's bearing strength from the equation as well.
_"if the bolts themselves do not fail, like what happens with rotten wood."_
A deck made out of rotten wood is unsafe, full stop. Doesn't matter HOW you construct it! Exposed wood will tend to weather, warp, crack and rot over its lifetime, and periodic inspection and maintenance is mandatory. *A deck is NOT "set and forget," and there is no need for the carriage bolts to be, either.*
John Dough if you're worried about the strength of the wood, use better wood, or a thicker beam, or place the bolts a bit lower on the beam, or use a timber-jointing plate as used for nailed roof trusses. Better not to cut into the timber and expose untreated wood and create surfaces to collect damp and standing water.
William Chamberlain Every time you cut a piece of treated wood you expose "untreated" wood. By your logic we shouldn't cut anything.
Skinny Moose you can and are supposed to treat the surface you cut...
how do you determine the length of your carriage bolts? In this example, the material is 5 1/2 " - so what length bolt do you specify?
As far as the skill saw issue, SKIL was the first company to make a widely used citcular saw AND in the US the name SKIL became a generic name for this type of saw. My dad called them skil saws and I still do.
let me know when you’re grilling out on your deck and you sheer those carriage bolts off there, skip! 😆
Or building inspector comes to check out new deck, sees it was built wrong, and orders it torn down..
@@chrisburns5691 To be fair, it probably depends on application. Those carriage bolts looked to be about 1/2" and combined would have significant strength. This is the wood equivalent of a rivet. Now if you have a large deck that needs to support thousands of pounds, not the best way. Small deck designed to hold 4-8 people, probably just fine. Also, I don't like notching the 6x6 on the side. Now the load is only put on one half of the post. Furthermore, there are better attachment options out there.
@@SpaceMonkey2385 i agree that they would be strong enough, my point is that they wouldn't pass code. My preferred method when I've built decks in the past is to rest beams on top of posts, and attach with appropriate hardware. Notching is better than just the carriage bolts, as the point load is transferred directly to the solid bearing of the 6x6. Still I prefer resting the beam on top, when I've built decks in the past.
As a carpenter I've learned what will pass an inspection and what wouldn't. Supporting a beam off carriage bolts alone would not pass an inspection, at least around here.
@@chrisburns5691 🤣😂😂 it passes code everywhere I’ve ever been. The other way is fine depending on application. Some engineers want it done that way when you set porch posts.
@@DonnyBoy286 interesting, doesn't meet code anywhere ive worked, and definitely not common practice. Typically set beams on posts. Would never fly for a 2nd story structure.
I've been debating notching a 4x4 post vs not for a playground. I've only seen not notching unless it's a 6x6. Can I get some expert tips?
Notching is not allowed by code in the IRC (which most of the U.S. uses). To connect beams to posts, you should use brackets that are specifically designed for the purpose. About $5 at your local hardware store for galvanized (a lot more expensive for stainless, but stainless is necessary in coastal areas).
Simplier to set the beam on TOP of the post and use either a tie metal plate or nail/screw/bolt a 2x6 on either side of the post to build a pocket. 30 years later with treated lumber my deck is still standing !!
I have just calculated the shear strength of a 12mm (1/2") carriage bolt is between 56 and 72 tonnes.
That is assuming the moving surfaced do not deform
I would be happy to use a 50% value for my structural validations.
And there were TWO carriage bolts !!
You need a lesson in structural mechanics my friend.
Regardless, it's the code in my area, so someone else agrees with him.
It’s the bearing stress in the wood, not the shear strength of the bolt that makes a bolt only joint weak.
His example was not the same.
That's way better than using flex tape I'm glad I saw this! But seriously That totally makes sense I never would have thought of it. Great video!!!
I've always used oversized posts and notched them to support the cross sections. Never had a problem
Numb nuts, what's going to shear the carriage bolts, an M-1 tank?
Anton Bouchette
The pressure of weight on the wood can push down on the bolts and split the wood. If you use a lot it will spread the load.
I was just thinking about this issue and this video popped up on my phone. I will try it out and see. Always used carriage bolts and cantilever method. Maybe I can now drive my car up on the deck with my pet elephant. Seriously. Nice having options.
While your method my be code and perhaps a stronger way of construction. I've seen many many decks and never not one single time has the failure of the deck been due to the carriage bolt sheering.Its always rotting wood,splitting wood, or some other reason but never has it been due to failure of the carriage bolt.
I thought most bolts are around 10 to 20000lbs of tensile strength so how could you ever have that much weight in that small area
@@jasonbrown7258 exactly
But when the wood gets older the pressure on the holes around the bolts may brake and cut through the beam. The method he showed is much more durable but for a different reason.
@@Sauromannen yeah definitely prefer his method. But he was saying basically that the bolt couldn't handle the sheer strength, which ain't really accurate. As you said the timber would probably fail first.
Your correct, it's not that the "carriage bolt" doesn't have sufficient strength to resist shear loads... it's the wood that will fail. Such a statement in court would get you laughed out... such a statement in the work place will get you kicked out.
I just built my deck and I attached the beams to posts with finishing nails. They were on sale and fit nicely into our budget.
Should have used carpet tacks...for strength!
I like your style. Around here we call that "DYOT" - Do your own thing.
@@inthewoods5471 One should do, I do not want to contribute to a higher carbon footprint!
Did you build my deck as well?
You must have been the guy that built my deck. He figured that no ledger board flashing was cheaper for him than buying it at Home Depot.
which way would the notched side of the post face the house or the back or the deck?
Didn't know there were that many professional carpenters watching "how to" videos on TH-cam.
We like to watch amateur bunglings. People like this came from Mexico and called themselves carpenters. Ruined my wages from the 80s. Journeyman carpenter from First year apprentice in 74. Till i retired 10 years ago. Superintendent for 5 of those years in the early 80s. These people have had no real training.
@@jerrynewberry2823 your so right. Very few companies train anyone nowadays. No time. Not enough profit. Overhead is to high. Yet a 500,000$ house only cost under 200,000 to build. Wheres all that profit going?
It is our civic duty to call out purveyors of BS :-)
A nice big washer on the head side of the bolt, this guy is a REAL professional. Scary
i've never seen a washer used on the head side of a carriage bolt. isn't the little square part supposed to grip into the wood to keep it from turning when being tightened?
while i agree, this method demonstrated here, is the better way...i've never seen the "go thru bolt" method fail.
Thats because the shear strength of carriage bolts are incredibly high.. The wood around the bolt would start failing before the bolt does. You could always go around under the deck and shore up some wood under the joist and tie it into the post if there is any sagging etc or wood failure.
Neither have I. Except for failing a code inspection, if the inspector bothers to look.
It would take a lot more measurements to notch the posts when building on uneven ground.
@@RSoles-hz9nc The trouble I have seen with through-bolts is that they invariably loosen up causing the post and joist to drift out of square, not to mention that where I live inspectors would fail them every time. The ones I see are usually on homeowner or brother-in-law decks that were never permitted.
Are you making sure your layout is square, and do you use a plumb line to determine pier location before locating and measuring the posts? That is how I do it and although it is not perfect (what is?) it always gets me to within about half an inch or so for the post location which is close enough for the pier, then I measure the location for the notches after determining exactly where the rim joists will be located. I also use scrap lumber to do a mock-up especially for larger decks and that helps. I'm not trying to insult your intelligence, just trying to be helpful.
@Mr TriL it depends on the conditions, type of wood used, and how the deck is finished.
You could be using your speed square as a guide for your skill saw when cutting across your beam.
until you are competent enough to cut to a line :-)
I sure didn’t trust any bolt when I built my deck. I dig this video. Perfect way to do it.
But you trust nails for your house?
I guess my truck axle is going to fail now that i've watched this. better put it on wood blocks quickly!!!
It’s the internet, everybody’s an expert. 😉
Best comment so far!
Matt P. The guy in the video sure isn't.
@@MrDavidBFoster you don't need to be a expert to know common sence
KEYBOARD COMMANDOS.. LMAO
Everybody except everybody ELSE....
I'm going to be building a porch into my trailer and it's going over a concrete pad and I can dig holes to set the post because of city sewer line and gas lines, but I thought I saw where there bases I can secure to the concrete to set and hold my post into place and was wondering what they are called and what would be the best kind to get and how to put the secure screws in the proper way for maximum safety.
"These things have no shear strength"
*proceeds to demonstrate BENDING stress, not shear.
No moment in shear. He showed
bending
I wonder if he first tried to break one of those carriage bolts. Can you imagine how much force that would take? The wood would fail far before the bolt shears
Sooo true!
Richard Miller that’s all you can ask if any fastener is being stronger than the material.
@@RichardMiller-tq6ut around 5000lbs shear strength on 3/8" carriage bolts. So with 2, you're looking at 7500lbs-10,000lbs of weight you can put on that beam before it might snap. So unless you're planning to drive a big truck over your deck, it's probably fine.
Straight to the point and no dragging it out to 15 minutes. Thank You !!!
Question....what do w e do with post and beam timber framing? No bolts, no nails, mostly just tight fitting wood connections with wooden pegs. Now, the old barn still standing built by farmers, not one of them an engineer. Snow comes...3 ft deep on the roof, then it rains and the snow holds the addition water weight ...for a while. Maybe even 20 or so blizzards later, with 4 or 5 with following rain. Will the barn still be standing ? I bet it will. They are still standing and still in use. BUT...our steel boat storage shed
, in Lake George NY collapsed in about ‘79 or ‘80. The storm dumped 3 ft of snow on the almost flat roof, then it rained.
Several 30 plus length cruisers were inside. A number of boats were Totaled. The solution....put a snow blower on the roof and blow the snow before the rain. If you can’t, build another boat storage building. OR maybe get a bunch of Amish to build you a big boat barn. Timber framed of course . I am agraduate Civil Engineer and served on the national building code for elevators in my career. Our goal as having standards establishes for public safety was to do the best we could to protect the public without breaking the financial back of the owners and contractors while insuring long service. It is possible to build a deck that would still be intact after the tornados, blizzards and fires passed. Nobody would buy one. It would be ugly. Hire the farmers to build your decks. Problem solved.
Bless you all.
JoeB
I built mine 12 years ago the wrong way, with just wood screws and it hasn't moved an inch... then again I don't need a deck strong enough to park a car on either.
Lone cruZader I only use this method on 2nd story decks ..
Not park a car
Drop a car from thirty feet!
Try to take a couple of those wood screws out and see how much metal you actually have left. You’re on borrowed time. I guarantee it.
We do 3 ply beam right on top of the post. a lot stronger than the old way
Four years ago I saw an extension with joists bolted onto the sides of the stumps. Not sure if it is still standing.
Span of a double 2x6 beam is limited to about 6', so each post would have about 36 square feet of deck it's supporting. Deck loading is typically estimated at between 50 lbs and 100 lbs / square foot (higher in some locales). Deck load on each post would then be between 1,800 - 3,600 lbs. Load capacity of the 6x6 post is 20,000 lbs. Standard deck footing on clay soil is load capable of about 5,000 lbs per square foot. Most guys put a 12" circular concrete footing under each post, or about 0.8 square feet. So the footing would be rated at 4,000 lbs. Shear strength of even cheap 1/2" carriage bolts exceeds 10,000 lbs, and there are two in the beam, for a minimum capacity of 20,000 lbs, typically closer to 40,000 lbs. Results: the concrete footing in clay soil exceeds capacity estimates of the deck by just +10%. The 6x6 post exceeds capacity needs by +300%. The carriage bolts have a safety margin of between +300% and +700%. The doubled 2x6 beam is right at capacity in this "design," and is the weakest point. Expert advice would be to increase the beam to doubled 2x8. Notching the posts adds some strength, but only to parts that are already the strongest part of the deck in this video.
🍻🍻🍻🍻🍻
I would not cut the treated beam, I would run the cross beam on the top of the vertical beam and use a metal plate or bracket to hold it in place.
Thats actually how I thought you where suppose to do it. Have only done 3 decks in my life and we did them all that way.
exactly right. Use the post as it is intended, put the beam on top of it.
That's right Jack, that's another way and probably the better one.
By code, that's the only way we can build a deck in the Chicago area. Standoff bracket at the footing and metal post to beam connection at the top.
What about all four corners of a deck? This method seems practical for a single beam, but the deck I’m build, for example, is detached from any structure and will also be supporting a hip roof.
I was going to make my own box beams and go all the way around and just use carriage bolts to secure them but now I’m second guessing. My posts are 6x6...run joists 2x10....deck will be 12x12. Any suggestions?
Where you building. ?
nice job .... cant bare to to see a Milwaukee called Skilsaw hahahaha