Post Level – https://geni.us/QLA5
Post WaterProof Sleeve – https://geni.us/iA7uoyJ
Flex Seal- https://geni.us/LZ6pN
Sika Post Expansion Foam – https://geni.us/YI4sLCL
There are a lot of different methods for setting 4×4 and 6×6 posts. I have made many mistakes over the years and combined my lessons learned into this ultimate guide to properly set a post for your fencing, deck, mailbox, or other DIY projects. In addition, I will show you a way to extend out the life of your post by 2X or 3X and avoid the most common point of failure.
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Friends Don’t Let Friends Tape Outlets T-Shirt: https://geni.us/ifioHVc
DISCLAIMER: This video and description contain affiliate links, which means that if you click on one of the product links, I’ll receive a small commission.
how’s it going you guys it’s Scott with everyday home repairs and today I want to show you a classic DIY project and how to properly set a 4×4 post now most homeowners are doing it wrong there’s one specific step if you do not do will lead to early failure it can cut the Project Life in half and lead to rot on your 4×4 post which means you’re just going to have to redo the project a few years down the road there’s also a little bit of debate of how we do the concrete so I’ll show you my method and also at the end once it’s fully set up I will actually remove the post showing you how consistent and solid is the concrete so you can use that information for your own project so let’s jump into it now a quick tip as you select your ground contact pressure treated lumber is avoid where the heart the center of the Rings is on the edge once that dries out it could lead to more twisting and warping compared to ones that are in the center so we’ll start off by digging our hole I just removed the side I want to use that later on and I use a combination of that Spike tamper to loosen up the material and then take it out with a standard post hole digger now as we all know this is quite a bit of work and if you want to get in augur if you have a lot of these that might save you time but what I’m shooting for is the diameter of the hole is three times the width of my post and then for the depth the best practice is how much you’re going to put above grade you should be putting half or 1/3 that distance below grade so for my instance I’m going to be 60 in above upgrade so that means my hole should be 20 to 30 in deep just make sure that you are offsetting if like me you’re going to put some gravel at the bottom I like to put a couple inches down at the bottom and then just use the post to Tamp that down then I check my distance I’m 60 in above grade now from the gravel I’m at about 26 in so I’m right in heart between that 20 to 30 in which is best practice just take in account if you’re doing anything structural you might need to go below your frost line in my area that would be 34 in so I need to go down quite a bit more if this would be some kind of deck build where we’re putting footings in the ground so now I go ahead and use a post level which just frees up your hands and gives you a bubble level in both directions that we’re going to Plum things up and then I’m using 1 by two stakes 3T long with screws already in so I can just attach those quickly to the 4×4 post sync two different Stakes that will hold them and then once I get the stakes in place then I’ll actually start checking my Plum and make sure the bubble is right in the middle before sinking that last screw now you want to check multiple times to make sure you don’t want to just check once and then go down and secure your screw because it might pull that in one direction or the other and then you will not be Plum so check several times as you’re getting everything set and then that will just make the rest of your project that much easier and then once I get everything I do like to step back and just kind of take a look make sure everything looks good prior to going and setting our Concrete in now another option A lot of people are turning to over the last few years are these expandable foam it’s a polyurethane foam like the Great Stuff cans you might have seen it’s two parts so I’m going to break the seal in the middle and then mix that up for about 15 seconds this is extremely convenient just make sure you’re wearing gloves because you do not want to get this stuff on your hands so once you mix it up you just cut off the corner and then within just a few minutes really only takes about 3 to five minutes for it to expand to its final volume and we’ll just demo this in the bucket because this is not what I’m going to be using and I’ll show you why here in just one second we’ll do a quick time lapse and you’ll see how that expands out and I put a tarp down just in case it overflowed but actually just kept that cylinder shape and expand it out to that final volume and now why I don’t use this here is the bucket removed I got this big old cylinder of expandable foam it’s set up for 2 hours that’s what’s called out in the package but comparing to concrete it just there’s no comparison with this one I can just push in and there’s going to be some big voids in it so it’s just not going to give you I can even push the sides in it’s pretty soft so that 4×4 p post can wiggle and loosen up over time and it’s just not going to give you anywhere near as strong of a hold as concrete would maybe for some of your middle post if you’re doing a fence maybe you’re sinking your corner post below frost with concrete and then maybe you’re doing some middle post but let me know down in the comments if you guys have experience and what were the results that you saw but for now let me show you my preferred method now for me I’m going to go with quick CRS fast setting quickr to fill the hole and to secure this post now nice thing about F setting within about 4 hours it’s ready to go it has cured enough for heavy loads where you could build out your fat or start building your structure but this is where the most common failure Point comes in so here’s our ground surface right at this part of the post most people are going to fill a concrete a couple inches below the grade below this surface right here and then back fill with dirt or maybe the sod which we removed what that does it makes a concentration of moisture right here and then that is going to be your most common failure point and it’s going to really reduce the life of what you’re building so what I specifically want to do is use actually Flex Seal on this post now what I want to use Flex Seal for is the rubberized coating at this line right here 4 in above and 4 in below I’m going to coat it with the rubberized coating to help protect and seal this post so if moisture does form at that ground surface which it will it will have another layer of protection extending out the structural life of that 4×4 post there’s also pre-made sleeves you’ll see below the video I’ll give you a link where you can heat those up and it’s kind of like heat shrink it’ll shrink around that post and do the same thing give you a rubberized seal and protective layer for your post against that moisture so I’m going to use that post level reference 4 in above grade to give me a little line here which will guide my blue painters tape I’m just laying the blue painters tape down so I have nice clean Edge between the Flex Seal and the bare pressure treated post once that’s in place then I’ll just go ahead and spray on my coating making sure I’m going below grade 3 to 4 in as well as going up to that line then after 24 hours letting the Flex Seal dry I remove the tape and set two bags of the quickr fast setting cement in the hole if you’re less than 30 in deep you can pour the water right on top and it calls out for one gallon per bag and I always question this does it actually pull all the way down through so for you guys I’m going to let it set up for 4 hours and then remove it to see what the actual results all the way down in the hole are but for you guys you’ll back fill and also put back your side and we’re not worried about that moisture because now we have the Complete Water Seal from the Flex Seal at the top so I’ll just cut that side right around the post put everything back and now our post is completely set in concrete secure and has the water barrier but I want to answer that question quickr says we can just place the water one gallon per bag right on top and does that pull all the way down through so what I’m going to do is remove a little more side and start taking off some of the soil that we just put in and also opening up a little bit more of the soil around the concrete that’s been setting up for over four hours now because I actually want to remove everything together with this Jack to do that I’m going to actually put a little block on there and put two carriage bolts through this piece and then that’s what that farm jack is actually going to set under and help to pull the concrete out of the ground how is this going to work not really sure but I’m willing to give it a go to see how far down did that water soak in how far down did that concrete set up was it the complete hole or only partially down the hole which means we would adjust where we’re putting the water maybe every bag of concrete we’ put water opposed to just all at the end right on top so now we’ll use our 48 in farm jack here I got a couple 2x4s on their long end so they can take a little bit more Force going down but hopefully we’ll be able to work this up again I’m not sure how much concrete will still hold on to the post I’m not sure if the post will pop right out but hopefully this will give us a little bit more of indication of how far down did the concrete actually set up and how far down did the water go well good thing we tested this out because it looks like this is confirming ing my suspicions looks like the water only pulled down about 11 in of that overall 26 in and the concrete mix is bone dry below that so for best results you’re probably going to need to premix in a wheelbarrow and then go ahead and add your concrete mix to the hole making sure that you actually get a solid tube of concrete all the way down to the depth of your hole we always love to get your guys’ feedback remember the links will be below the video and description for anything we used here for reference on your own projects and if you want to check out another classic DIY maintenance item check out this video right here and that is how to seal and keep water out that crack between your garage and your driveway there are a lot of products on the market but they are not going to last for years and years that video will actually show you the professional grade way to do it so thanks for joining me on this video and we’ll catch you on that next one take care
50 Comments
Post Level – https://geni.us/QLA5
Post WaterProof Sleeve – https://geni.us/iA7uoyJ
Flex Seal- https://geni.us/LZ6pN
Sika Post Expansion Foam – https://geni.us/YI4sLCL
Friends Don't Let Friends Tape Outlets T-Shirt: https://geni.us/ifioHVc
DISCLAIMER: This video and description contain affiliate links, which means that if you click on one of the product links, I’ll receive a small commission.
There are several electrical companies that have began using that foam for most electrical poles. The one downside that is worth considering is cost, roughly twice the cost per hole.
Foam belongs on beer root beer or the ocean white with foam God bless America, but not in a fence post hole
Sir This video was far beyond awesome with much more advice and information than I have ever had. But that is good.! because this answers a lot of questions I never had but the information about all possibilities are answered. This video was fantastic. thanks beyond words.
sir…I strongly think you're doing way too much work on just one post. I have done way less then you, and my fence is still holding after 15 years or more
9:00 👍 Down side of dry pour
Forget the flex seal. Just torch burn the whole part of the post thats under ground. Wear a mask since its pressure treated. It will never rot out.
i like the flex seal , good idea,, what i would do is add water first and put part of the bag in then add water and the rest of the bag ,, when you pour the bag you can see the water coming up .. but your way is the best! thank you
Super video!! This info is helping me plan a project so consider me a new sub!! Thank you!!!🙏🏻
Just pour water into the hole before hand simples.
The first recorded uses of tar date back to the Paleolithic period (around 40,000 years ago), even at that time they knew that a waterproof sealant to the base of a fence post will trap water.
You are blocking in the moisture remember wood is hollows and the moisture goes to the l
owest point to drain out
You could just pour one dry bag, place the water, pour the second bag, place the rest of the water. It will all get set then.
Gravel is a complete waste of money.
In one year everything is packed with dirt.
This was a great video that answered several questions I had like:
1) Does QuiKrete fast set cure properly if you only put water on the top
2) A good product to seal the underground portion of the post from moisture
Thank you!
I do have a question. Why not use flex seal on the entire part of the post that gets buried, plus the very bottom where it comes in contact with the pebbles (drainage/leech field)? I ask this because concrete is porous, even after it dries, right? So, to prevent the part of the post that is underground from getting wet (ever), wouldn't we want to seal the whole post both above ground and below?
What you need to do is add water below and above of your drycrete. So you can add water in the hole first, or you can put some drycrete in, add some water, and then pour the rest of the drycrete in and add water on top so that the entire thing gets saturated.
He didnt seal the bottom of the post before he set it ….all that flex was stupid and a waste without hittin the end grain .
The expandable foam is used for setting utility poles sometimes. It will definitely hold a fence post
Thank you for this thorough tutorial!
This is by far, the MOST detailed and through review of a project I have ever seen, since joining YouTube 18 years ago! Thank you so much for doing this! I have to add a post on my property and this video has been incredible! Just subscribed! Thank you again!
I always filled my hike half way eith water than poured the bag in then more water on top. Never pulled it up to check but also never had a problem.
Great video, now ill have to test my method
I’ve been thinking about adding a small 5×20 foot screened in porch jutting out from a sliding glass door in the back yard. It goes out from the house 20 foot. (Approx measurement.) instead of setting 6 6×6 into the ground, digging 6 holes, adding concrete, then place a metal cap on each one that holds a 6×6 pole. Seems it would be easier to repair later and maybe last longer.
Put you water in the hole first then as you add the concrete it will all get wet. I put in about half the water dump in a bag concrete work a couple of times with the spud bar then add the rest of the water then pour in the next bag concrete and work it again with the spud bar. Solves the problem of the water getting to all the concrete and makes sure no air pockets or dry places.
As for the concrete, you can do exactly what he did…but…as you add water, take a steel rod (piece of rebar works great) and work the water into the dry mix till the hole is completely mixed.
No fuss…no muss
Nice Jack. Why wouldn’t you premix it? Why even waste our time. Also you need to start with a pressure treated post, if not you done all this spraying for nothing.
I’ve had to replace old posts that fail from sprinkler water rotting them out. I can remove the old posts and hand scoop out the rotten wood from the old concrete footing, and then put in a new post in the old footing. Next time I’ll add Flex Seal – thanks.
good job poop
I like the Flex Seal. I had put a sleeve but the Flex Seal I think is more reliable. I don't like the dry pour: just mix the stuff and the pour.
Honestly there is no reason you shouldnt mix the concrete with water and then pour
All that prep, but didn’t paint the bottom cut of the post? Don’t worry about the dry mix at the bottom, it will eventually harden after a rain fall.
Couldn't you soak the bottom of the pole in used motor oil and protect it like that?
I painted the bottom of my posts with bitumen, watered the hole then added postcrete in increments along with water and pushed a stick through it to make sure it mixed. Time will tell. The best tip here is to really take your time getting the post true and my experience says you want about a third of your post in the ground so factor that in against the height of fence panels. My panels are 4 foot plus gravel boards so using 6 foot posts meant I don’t have the holes as deep as I would have liked them. Cheers
Your concept of protecting (4” above and below grade) the post is good. However, the ground moisture can still destroy the wood where you don’t protect. I would think that it’s better to protect the post all below and up 4” above ground. In addition, what I usually do is to pour plenty of water in the hole prior to pour in dried concrete; this will ensure the concrete to set appropriately. Another method is to pour water in the hole while pouring the concrete.
Wow what an exception video. Everything so well explained especially pointing out, what Not to do. Thank you.
Thanks. Never knew about flex seal. Now I do. I also shape my concrete to form a high point at the actual post then slope away from post to the out edges. Then I add a good amount of chalk all around the post right where it meets the concrete. This helps direct rain water away from the post or entering any small spaces between the post and concrete. I have been painting the area that you use flex seal with a couple extra coats of wood preservative. Maybe I'll try flex seal instead. Thanks again
You put a lot of trust I. That flexseal. I'd still bring the concrete above ground level
First of all, thank you now I will add my comments from my own personal experience… first of all when you take your post instead of putting the gravel in the bottom use your flex seal on the bottom sides. I usually do about three coats. Also when I start pouring in by fast drying concrete powder, I take a water hose and I wet it every few inches then I dump in more also while I’m doing that and make sure to wear a mask because that dust does go into our lungs so again thank you for doing such a wonderful job. I’m looking forward to more videos from y’all and have a great day and this is.Journey in Gainesville, Florida 🌿🌎🕊️
I'm not sure why anybody wouldn't premix
You don't have to premix the concrete just add water as you go and mix with a stick or pole then it will be mixed from bottom to top. Just make sure to recheck the plumb on your pole as the concrete could move it slight out of plumb.
What a joke .. concrete lol .. FAST 2K Blue EXPANDING FOAM is 1000 times stronger, cheaper, faster and is not corrosive to wood like concrete. Never use concrete ever again. BEST PART of expanding foam … you can carry enough expanding foam for an entire fence project in one grocery bag.
Never use the cheapo expanding foam from home deppot, use the Fast 2 K closed cell (Lowes/Rona) .. it's so tough you can't dent it with a hammer !
great stuff! Thank you!
Why are you giving advice on the foam based on how you can press your hand in it if you have not even tried it for a extended amount of time? That is AWFUL advice. It seemed like you used flimsy bs evidence to base all your other opinions around and that is a really lame method of logic. In the future, actually USE IT for a few years and have ACTUAL information about a practical application rather than a childs reasoning. FYI this stuff is used a lot and for the last decade and thats why its still around. It works and works well. The main reason for not using it is its stupid expensive. Dont mislead your viewers. Also who doesnt premix? Ridiculous.
water first
Yes it was dry below 11” but eventually when it rains it will get wet and harden up like it’s supposed to
The spike digger is called a "SPUD BAR". The concrete will continue to pull moisture out of the soil until it is fully set. I've dried poured concrete around post for years and it has always been fully set through the entire pour.
I just dump half the bag. Add water. Then dump the rest and add remaining water.
wow!!!! thank you for all that extra work re the concrete!!!!!! will need to mix first I see!
I love your thorough explanation and your illustration in pulling the post out of the ground to show the dry mix. New to me was the Flexseal coating you applied. . Impressive information. Thanks, subscribed to your channel!
Here is it 48" for below frost line… you don't need a gym when you need to shovel snow of dig holes for fences! 😉
Edit: As for the Flexseal, you put it all the way on the surface of the wood that will be below ground as concrete will attract moisture naturally.
why couldn't you just mix it in the hole so it will penetrate all the way down?