# Lag Bolts...



## joecaption (Nov 30, 2011)

Going to need more info.
4 X 4's are no longer expectable in most areas and for sure not just attached to the outside of the post.
And through bolts only.
Must be one small deck if your only using 2 X 6's. That's the size I'd use for a stoop.
Get a permit for this?


----------



## GBrackins (Apr 26, 2012)

what is the purpose of the 2x6's?


----------



## TheCamper (Dec 4, 2009)

If you provide additional information you will likely get back some very good direction. In my experience you may not place a post into concrete. You need to install a poured concrete pier below the frost line and place a "wet anchor" in the pier and then set your post into the wet anchor.


----------



## Robpo (Mar 30, 2014)

smittyd said:


> Hello. What size lag bolts should I use when attaching 2x6's to 4x4 post that I have cemented into the ground? These 2x6's will be around the bottom of the deck I'm building. Thanks...


 Best I can come up with is nail a 2x4" below the 2x6" and use 2, 1/2 through bolts.


----------



## smittyd (May 7, 2007)

GBrackins said:


> what is the purpose of the 2x6's?


4 2x6's will be put around the bottom attached to the 4x4's. Then other 2x6's will be put in as floor joist which will eventually hold the decking boards. I'm going to lag bolt the 4 2x6's to the 4x4's. I just need to know what size lag bolts for strength. This is a 10x10 deck for a hot tub.


----------



## woodworkbykirk (Sep 25, 2011)

as already stated 4x4`s are no longer acceptable for deck posts unless they are solely for a hand rail, if they are used for bearing posts the deck will not pass any inspection


as for 2x6`s for joists on a 10x10 deck , the only way that will fly is if the deck is fully supported by sitting on a concrete pad or something of the like. 2x6`s are no longer accepted as a joist and if your planning on putting a hot tub on the deck theres a very good chance that deck wont last a season. i wont build a deck thats supporting a hot tube with anything less than 2x10


----------



## joecaption (Nov 30, 2011)

Way under sized floor joist and rim joist!!!
Not even close to minimum code!


----------



## ront02769 (Nov 28, 2008)

smittyd said:


> 4 2x6's will be put around the bottom attached to the 4x4's. Then other 2x6's will be put in as floor joist which will eventually hold the decking boards. I'm going to lag bolt the 4 2x6's to the 4x4's. I just need to know what size lag bolts for strength. This is a 10x10 deck for a hot tub.


You are WAY WAY under built for a hot tub!! Go to the website for hot springs hot tubs, poke around and ou will find a deck designer application which is free. Give it a look and IT will ALSO tell you that you are wan under built?....but will also give you specific plans to do it correctly. Ron


----------



## Daniel Holzman (Mar 10, 2009)

To the OPS: I am going to presume that you are building the deck in an area that does not have any codes, or perhaps there are codes but they are not enforced, or maybe your project is exempt from code. Whatever the case, you ask about the required size of lag bolts. So now you run into a curious problem.

The majority of deck builders construct their deck in accordance with the Prescriptive Residential Deck Construction Guide, available here http://www.awc.org/publications/dca/dca6/dca6-09.pdf.

This guide tells you everything you could possibly want to know about constructing a deck, including sizing of all elements, how to put them together, allowable materials etc... But you clearly are not following this guide, for whatever reasons, so nothing in this guide is useful to you. So the question becomes, "Do You Feel Lucky?" Well, do you?

There are many ways to design a project. You can follow code, in which case there is little to think about, and not a whole lot to worry about. Or you can do your own engineering, which is what you need to do. You need to calculate the shear forces on the lag screws and the wood, and determine the required size of the lag screws, and the minimum size of the wood members you are connecting, based on fundamental principles of mechanics. And that is not very simple, and since you are asking on an internet chat forum, I presume you do not know how to do it. This is why most people keep to the code, it has worked out all the gruesome details of sizing lag screws (actually requires through bolts) and everything else.

So my suggestion is to download the guide, read it, and if you don't like it, or think you can do better, go for it. But you are unlikely to find anyone on an internet chat forum who wants to do the mathematics of computing the shear forces on those screws to size them for you. And if you do find someone, be a little careful, since a licensed professional who knows how to do it is prohibited by law (at least in the United States) from practicing engineering over the internet, which leaves unlicensed, non-professionals to do the work for you. Are you feeling lucky?


----------



## Robpo (Mar 30, 2014)

Daniel Holzman said:


> To the OPS: I am going to presume that you are building the deck in an area that does not have any codes, or perhaps there are codes but they are not enforced, or maybe your project is exempt from code. Whatever the case, you ask about the required size of lag bolts. So now you run into a curious problem.
> 
> The majority of deck builders construct their deck in accordance with the Prescriptive Residential Deck Construction Guide, available here http://www.awc.org/publications/dca/dca6/dca6-09.pdf.
> 
> ...


3/8" x 3 1/2 inches


----------



## smittyd (May 7, 2007)

woodworkbykirk said:


> as already stated 4x4`s are no longer acceptable for deck posts unless they are solely for a hand rail, if they are used for bearing posts the deck will not pass any inspection
> 
> 
> as for 2x6`s for joists on a 10x10 deck , the only way that will fly is if the deck is fully supported by sitting on a concrete pad or something of the like. 2x6`s are no longer accepted as a joist and if your planning on putting a hot tub on the deck theres a very good chance that deck wont last a season. i wont build a deck thats supporting a hot tube with anything less than 2x10


Yes, I will be putting pads as support under the 2x6's to help support the hot tub. It will be beefed up in the center area.


----------



## smittyd (May 7, 2007)

smittyd said:


> Yes, I will be putting pads as support under the 2x6's to help support the hot tub. It will be beefed up in the center area.


I live in south Texas. My 2x6's will be only 4 inches off the ground. Again, and will be supported with cement pads.


----------



## ront02769 (Nov 28, 2008)

smittyd said:


> I live in south Texas. My 2x6's will be only 4 inches off the ground. Again, and will be supported with cement pads.


Missing something I guess. If you are going to fully support those two bye sixes by putting them on a cement pad, what do you need lag bolts for?? Pour your slam and set. The frame on it direct. But first do lookup the very detailed construction guide on the hot springs site. Ron


----------



## smittyd (May 7, 2007)

ront02769 said:


> Missing something I guess. If you are going to fully support those two bye sixes by putting them on a cement pad, what do you need lag bolts for?? Pour your slam and set. The frame on it direct. But first do lookup the very detailed construction guide on the hot springs site. Ron


Cement pad was the wrong word. It's cement blocks strategically set under different 2x6's to help support the weight. Thanks...


----------

