Fence Post Foam vs Concrete | STRENGTH TEST

No concrete fence post install !
Fence post foam or concrete. What is better ? In this video i will be putting sika fence post foam against post crete for the ultimate strength test.
2 timber posts will be set in the ground. One with fence post foam and one with a rapid setting concrete.
We will then see which one performs best.
I hope that this video helped you in some way, and if it did, please leave a comment for me in the comments section. I love to hear from people who gained value from any of my videos. I always respond to comments, so would be great to hear from you guys ! 👍
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Time stamps
0:00 Intro
1:22 The test setup
2:13 Setting the concrete
2:37 Mixing and pouring the post foam
4:00 Watching it rise
6:10 The ultimate test !
6:55 Pulling the posts out of the ground
8:39 The verdict
#foamvsconcrete #fencepostfoam #doespostfoamwork

[@brucehokel4618]

I rarely ever weigh in on comments but I have to on this one. I have a large acreage and have foamed in over 150 5” and 6” posts, along with numerous 4” and 6” square posts. Expanding foam works better and expands more if the temperature is above 70 degrees. I do not use , but have used, the SIKA prepackaged foam. I buy the foam I use in 1 gallon containers and mix with a drill, proper mixing is absolutely key!!! I have had to pull several end posts to put gates in and they hold great. Plus when I pulled the posts, I used a saws all with a 18” blade to cut off the foam. The post was completely dry, it had been in the ground 6 years and looked brand new still. I let the foam rise above the ground and use the saws all to make a small cone from post to ground so the water runs away. The foam is a bit more expensive then concrete but a lot less work! Concrete is porous and actually absorbs water like a sponge. Concrete never truly sets for years, the chemical reactions (hydration) is what causes it to cure. Concrete wants to absorb water and causes the wood to rot sooner or later. The weight on the bottom of the post is nice but the wood will eventually rot. Foam seals the wood, it will not rot or absorb moisture, sealing it. Foam “shrinking” is not a thing. The ground around it can shrink due to less moisture but the foam does not. Improper packing of the soil before placing or water saturated soil is the cause, not the foam. It can not shrink, it dries to a very hard substance. Concrete does the same thing, if the ground surrounding it wasn’t untouched soil or compacted properly, something better than a 2x4, it will move when the ground shrinks too. If you make your post hole a slight bell shape at the bottom, the frost locks it down. Ground freezes from the surface down. Doing this helps to stop any heave from a deeper freeze. Also, if you move the curing foam or improperly mix the foam, it can create voids . But it will not if you follow the instructions. If I get the mushroom around the post from the foam, I just add a bit of new foam to seal it and then shave it down when cured. Power and telephone companies have been using foam for years as it is far superior, my father worked for a Rural Electric Company for 35+ years and remembers when they first started using foam. He said it was a game changer. I have used foam for over 10 years on every type of fencing and miles of barbwire, we stretch the wire and have never had a problem. Sorry for the long post, I just read so much bad information and had to chime in.

[@ayungclas]

Thank you for the information from your experience.

[@jhandle4196]

How much of the Earth's ozone layer does it destroy? That's an important consideration no one seems to want to consider.

[@gowanlock]

​@@jhandle4196 concrete is one of the most destructive carbon / environmental damaging substances we build with and we use millions of tonnes a year. A small company using it for fences doesnt make a difference

[@XxsteamerxX]

I have used foam in situations as a tech in telecom. I know how it works. One of the issues I have with using it to set posts is the weight that concrete adds to help with creating a lower center of gravity and a "foundation" for the fence. Especially is this crucial on gate posts. The extra weight of the swinging gates will inevitably cause those posts to lean.

[@jhandle4196]

not to mention that foam is a pollutant that has no business being buried in the ground.

[@loriumc]

Thank you for the video. When I used the foam, I poured it against the fence post and above ground level. That way the foam will coat the post and seal it against water. (It will slide down the post and you won't get that rolling effect that you see in the video.) I also went back a couple of days later with a utility knife (any knife would do) and trimmed the above-ground foam away from the post at an angle.) Finally, I think the bags cost me between $6 and $9. If you are digging a wide hole, consider getting two bags. At my age, it's a lot cheaper than a strained back! Thank you again and no, I don't work for them!

[@FreakyTV_Live]

I appreciate this honest experiment and review.

[@EthosAtheos]

3 years ago I installed a fence using the same foam you tried. My exp. so far is very good. No movement and the fence is holding up through winters well. I used 2 bags per post because I used 3 foot deep holes with gravel beds at the bottom for a drain. I did concrete in some of the posts that were shallower due to ledge. The concreted posts all have 3 half inch rebar glued into the ledge. They don't move at all but took 10 times longer to install. Over all if you need a mail box or some free standing post that doesn't benefit from the concrete's mass, I'd use the foam.

[@pyromethious]

This is what I'm pondering. Our mailbox post has been 'drifting' away from the concrete road because the mail lady likes to drive right (literally) in front of it and off the road. We Had grass and solid land there, but now it's a big sandy ditch and the box has moved probably a foot. IDK if I'll ever have the $$ to Do it, but I'd like to add to the driveway and in that area put in a permanent square post hole that will have some sort of mechanism that allows you to apply pressure to the wooden post itself (that you insert into it). IDK, one of many things in my head that I'd like to do.

[@cynthiakiy1406]

Thank you so much for doing this. Saved me time and money.🇨🇦

[@CCKMedia]

Thank you! I was just about to use this foam to set a 10-foot gate post!

[@federicomaisch8019]

Very illustrative, thank you for sharing

[@dylanm4339]

i went 4 ft or 1.22m deep and used a 1.5 bags/hole, 1 set bag and .5 bag later as filler. make some sort of plastic cone (oil it) for the overflow, this will provide some downward pressure as the foam expands and help resolve the water issues mentioned. Both methods would be a lot stronger filled to the top too

[@georgelowe8583]

Thanks, you make a great point between the two methods.

[@YY-ei1gm]

Very Helpful! Thank you!

[@reasoningtruth]

Up here in wet rainy Oregon, some of us use Pea Gravel for the post. It helps a few ways, like if the post moves even a fraction in the wind the gravel sinks and tightens the post continually never letting the post get loose. (Just keep the pea gravel capped off). Also, the water has a drain away from the post ground level so the water rot in that spot is no longer a problem. Another way it helps is that there is no concrete mixing! Many up here think it's faster and better.

[@JamesMontana]

The whole post hole is filled with pea gravel ? Thats a new one one me and i cant see it working if im honest.

[@gary24752]

@@JamesMontana concrete is the worst thing you can use. I retains moisture between the concrete and the post. The post eventually gets saturated and rots off at the top of the concrete. Foam is used by all the utility companies for their poles that weigh about 1500 pounds so I think your fence posts should be all right. A post that has gravel round it compacted in six inch lifts is not going anywhere and it allows the post bottom to dry out. I would coat the bottom of the post with asphaltic foundation coating or put 30 pound felt around it prior to back filling.

[@DG-kq8zf]

Yep. Pea gravel is self packing. Often used as a base for filling big holes and topping off with concrete.

[@reasoningtruth]

@@DG-kq8zf When the old concrete guys all say pea gravel is the way for post, you just got to listen. Doing the same mistake over and over has got to learn them something. I would think. They sure are firm on the gravel!

[@davidelliott5843]

The subsoil where I live is clay. It retains water so timber posts will never last long. We use H section concrete posts set in concrete but this foam is probably just as good. All methods are only as strong as the surrounding soil.

[@imianco8079]

very helpful! thank you from milwaukee! i am installing a hefty modern mailbox and was wondering and this helped loads lol

[@BatsinaBellFree]

Thank you! You've made our mind up.

[@533lpunit]

Thank you for testing this

[@JamesMontana]

Youre welcome mate 👍

[@rayvanderjagt4314]

I used the foam for my mailbox over a year ago, still rock solid!

[@Kekker1944]

I used this for My mail box post, all I can say is WOW and WOW Very solid and strong

[@EYNugget]

so glad you did this vid!

[@MrBluesluver]

Thanks from Kansas, U.S.A. Great informative video. I'm needing to set a couple gate posts and maybe new corner post. Think I will stick with the old quick-crete.

[@Bokoyo]

Thank you, very helpful

[@GordonWeis]

I used the foam product on two treated 6 ft posts and it worked great and both posts are totally solid. I used a post hole digger and that left a hole just a little larger than the post. The mix in both cased grew just slightly above ground level.

[@this_tj_krawls]

Yeah his holes are far too big for a 4x4 post. 1 bag with a proper dug hole fills to above the hole. Shave excess at a slope to move water away from the post. cover with dirt. Never had one of these fail on a fence or mailbox.

[@AlphaMachina]

He dug these holes way too big for foam. The foam works great when used properly. We did our entire fence with it and it's been rock solid through 3 hurricanes. Hurricane Ida hit us directly with the north-facing wall of the eye and our fence is still solid.

[@donaldso718]

Hey if I wanted to do a 4x4 post for string lights about 8 ft high, would sika be ok in this application? Also how deep and wide should my hole be for 8ft high post above ground? Thanks!

[@dubmob151]

seems like both would have benefited from a couple small lag screws being placed on the post so it wouldn't be pulled out so easily. The posts are too smooth to hold without adding some notches or irregularities to them. Don't think it's going to be manually pulled out with some screws or nails embedded in the post base.

[@dthorne4602]

​@@donaldso718 Yes

[@JW-bw7cc]

THANK YOU FOR THIS!!!

[@sixwestpoint]

Totally Random Watch but absolutely brilliant information, thanks for doing this test and great video.

[@duxdawg]

Good to know. Thanks!

[@OweEyeSea]

Love the mix of units used in the UK. Inches, feet, and kilograms.

[@stefanz6502]

Being American- I cannot comment on UK soil conditions. But here in the north east USA I dug a 36" post hole and used Post Fixit with a 4x4 post like you used. I mounted a substantial retractable hose reel that weighs about 40 Lbs. 3 years later, it has held with no noticeable tilting. You perhaps should have dug a deeper hole than you did. And yes, where I live we do have a high water table, but I make sure I tripe sealed my pressure treated post with deck seal-, paint, and a plastic moisture layer. I hope this helps.

[@brucekimbrell1258]

I.worked at Lowes for a few years and they had 5 gallon bucket with a post and filled with that same foam for a display. it had shrank about a inch over a couple years and was just wobbling around in the bucket ..they finally had to make a new one because it looked so bad!

[@42lookc]

You can't prove a failure better than that.

[@answerswithavideo4864]

In fairness a 5 Gallon bucket won't shape around the foam, the ground and dirt will. If it takes a year for it to shrink an inch the soil will keep up with it and keep it tight theoretically

[@stevenbeall9637]

Wobbling in the bucket, not around the post. The ground isn't a bucket. The ground will continously conform to the changing shape of foam, the bucket won't. That said, I would still use concrete, or just backfill with a very sandy soil which sets really strong and drains better. I live in a sandy soil region and most fence installers around here just do that. Problem with many concrete post installs you see is it rots where water accumulates on top of the concrete and breaks off there, then you have a hole full of concrete you need to dig out just to replace the post. Even putting a slope on the top of it is not as good a draining solution as just having the water pass straight past the post with a good draining sandy soil fill. Honestly, the only posts I would put cement around are the one's that have to be as rock soil as possible, typically the two on either side of the gate, so there's no door sag and even then I'll dig the hole 3' deep minimum.

[@davidgarner7948]

The utility companies around here (TXU) use foam to set utility poles. So whatever they use works well.

[@bryonmorawski5671]

​@@stevenbeall96379

[@Awesomeness12388]

Thank you! I would be really intrigued to see you do the same comparison with quick set concrete and post foam called "boa hold"

[@MazichMusic]

I've set posts both ways. I've had them set for several years now and both methods are rock solid. IDK what you did differently. I think the foam is certaily much easier for someone with a bad back or arthritis.

[@kxjx]

He didn't fill the hole properly and he dug holes that were far too big (diameter). You can see he easily pulled the post out of the concrete with minimal effort. Did basically nothing right. Terrible fencing.

[@surfmunki]

Foam is the way to go. I don’t think he mixed the foam bag properly

[@Unbendable74]

@@kxjx I saw that. The holes are way too wide.

[@Nicolasbotero1]

Foam is plastics. Why would anyone want to fill their soil with that?

[@kxjx]

@@Nicolasbotero1 I wonder how much the foam degrades over the life of the post. Its quite easy to cut the foam back out again; but if the foam is breaking apart/breaking down, or leeching anything nasty into the soil that wouldn't be good. Having said that, something tells me that the postcrete probably also has quite a lot of additives that might not be the nicest. And the carbon footprint of concrete is high (making the concrete, plus transporting all that weight). More good reasons to try to keep the amount of filler material to a minimum.

[@teddyboy252]

Good job mate

[@ImperialRis]

Thanks for the information.

[@tactical-daddy]

Back when I did satellite installations here in the US for customers that didn't want the dish mounted on their roof, we used the foam on a pole installation and then put the dish on the pole/pipe. We have had tornados come through and completely destroy homes and while the satellite dish was gone and the pole maybe bent a bit, the pole remained seated in the ground.

[@donnytalbert5232]

Junk,I've used this a couple times at work ,ok for line post but not for stand alone gate post,

[@johnkapel2128]

If you want the foam to work really well, and it will, you have to know the secret ingredient to add to the mixture. I found that if you mix up the 2 parts and start filling the hole, if you stop after adding 1/4 of the mixture and then sprinkle 5 oz of wheat flour on top, then add more mix and repeat with the flour, until you mix is all used up, you will get a much better quality of a setting. Another thing you could add is 2 1/2 cups of oatmeal.

[@entropydomain]

@@johnkapel2128 organic works best

[@jimdoe3288]

Did you tell any of them that it's actually ground based ?

[@dougb8207]

Your problem surprised me. I used a bag of Wika, and it set very strongly. The post is sturdy. My foam dried yellow color though, so may be different, even though it's also Wika brand. Also, I dug a very narrow diameter hole, maybe 6" to 7" diameter, and the foam overflowed over the top. I cut it off with a reciprocating saw, careful not to cut into the wood. Thanks for the demo.

[@bmfilmnut]

Like you, I was very skeptical of the foam product and it performed exactly as I expected it to perform. Thanks for posting this. Very helpful. That said, I would mix the concrete before pouring it in the hole. What you've done is a dry mix and dry mixes are much weaker than wet mixes.

[@NathanHarrison7]

Great video. Subscribed.

[@Daniels656993]

I installed a treated wooden fence 21 years ago around my back yard. Holes were dug 3 feet down by 10 inches wide and filled up with crushed rock around 4 by 4 posts that were also treated. This year out of the 50 posts, I had to change 3 that were broken 2 feet down in the soil due to various impacts over the years. I was easi.y able to pull out the top portions of the broken posts but had to dig 3 feet down to remove the rest and installed new ones in thier place. No matter how well treated wooden posts are, they will all eventually rot and need to be replaced but the point here is that it took 21 years. That's pretty good in my books and also, rotted or broken wooden posts are much easier to change when back filled with crushed stone than when back filled with cement.

[@mudspringer]

Great vid!

[@fredcomstock1100]

I had the ultimate test of fence posts set in concrete. During Hurricane Katrina in Mississippi, USA, posts broke off just above the concrete. Some posts shifted and others snapped laying about 25' down, sheered where the nails failed. I am a firm believer in concrete, though a pain to replace, but very sturdy. I am also a firm believer is using screws instead of nails as screws do not pull out unless they break.

[@Netbug]

Nice NPC flag.

[@mmike76]

Just drove by our fathers old horse ranch in Springdale Oregon where as teenagers some 50 yrs ago we built fences. Railroad ties at corners and pressure treated 6"X6" posts every 8-10'. 2x6 pressure treated upper and lower rails with galvanized 5' wire mesh. Hand tamped each post with a shovel full of gravel,dirt and always using found rocks when available. Smiled as I drove by. Those were fences. key note we put one electric wire to keep horses from rubbing fences loose. Spend your money on treating the wood.

[@av_oid]

Built a few fences with posts hand-tampered with dirt 30 years ago, replacing fences over 50 years old built the same way. Yes, don’t need concrete or foam, if you just take the time.

[@dantrav1927]

I had a VERY different experience with the foam, no idea what brand but mine was a different color and my post are in super solid 4 years later. I remember I used extra and had foam way above ground lever in the end. Couple days later I used a foam board kind of knife and smother it out level. BUT I would just use concrete next time. Just seems better. lol

[@CliftonMurphyjr]

If you add the foam correctly, its a much better seal against water. When you add the foam liquid you are supposed to make sure you pour it against the post on all four sides so that the post is coated with foam liquid even above grade. Also, lets fill the hole...lol..the foam should come above grade. We use a product by a different name (Fast2K), and its far superior to concrete.

[@toddrunyon]

Your comments are correct. He didn't install as noted in the instructions. I tried the foam this weekend to install a wooden mailbox post and followed the instructions as per the bag. it expanded much more than in this video and completely filled the hole creating a slope away from the post. Would I use it to install wood fence posts that will support a constant weight? I am not sure but it defintitely worked as hoped / expected in my instance.

[@user5.56]

so if he pour the foam in the hole a different way or made the hole smaller around.. your saying the wooden post wouldnt be soaked after 6days..? the post being soaked is Bad problem

[@toddrunyon]

@@user5.56 My GUESS is that he didn't mix the product correctly since it didn't appear to expand like it did when I used the product.

[@habeckkentrn]

@@user5.56 what I noticed, he only poured it on 1 side. If it has to run around the post, it's going to create those voids, especially more so when it starts setting up and hardens

[@NOBODY-oq1xr]

He is using it wrong that's right but in no way the foam is ever better than concrete except for ease of use maybe. The fact that it's missing the weight that comes with concrete alone is a big downside for anything that's bigger than a mailbox post

[@teamjesus6383]

Thank you

[@yarmonymatoid1562]

I've installed many field entrance posts with 16-20' steel gates. I've used concrete and foam more recently. I would never go back to concrete. The foam is easy to work with and if done correctly, it protects the post and is every bit as stable.

[@rimrejects]

What should he have done differently?

[@mrklean0292]

I don't know what you did differently from what I did, but I used an expanding foam product which looked like it came in the same packaging the one you used, but the foam was green. I used it six years ago on a post, and it is still as strong today as it was when I originally poured it in. I just went out after watching this and shook the post and it's still doesn't budge.

[@-sp00ky-]

So glad I found this before I put my new fence in. You've changed my mind about foam and concrete. Thanks for sharing 👍

[@muhammad8970]

The foam is good he didn't apply it correctly.

[@Tekagi]

Don't let this video influence your opinion; he didn't use the foam correctly at all.

[@silentfart5941]

@@Tekagi Feel free to point out what he did wrong ...

[@Tekagi]

@@silentfart5941 In short: he dug the hole way too big to use just one pouch. In detail: for a 4x4 post (3.5 x 3.5 inches) a 36 inch deep hole should be no more than 8 inches in diameter. If you pause the video at 18 seconds you can see a chart in the lower left of the packaging that spells this out clearly. Pause it again at 3:32 and you'll see the hole is at least 10 inches wide. When you use the correct amount of product for the hole and post size, it spills out the top of the hole and does a much better job filling in all the voids so you get a study post. It's still not as rigid as a concrete footing, but much much better than what he shows in the comparison.

[@jordinp2140]

I think it'd be cool to see a strength test for concrete set metal or wood fence post. And in the test you'd do 1 post with one bag of concrete, 1 with 2 bags, and 1 with 3 bags. That way we can see if we're getting the same added strength per bag. I think using a winch with a tension meter might be a good way to test the strength. Just an idea I had. Thanks for the content!

[@JamesMontana]

That sounds like a really good idea for a video. Thanks for the suggestion. I have a couple of other videos coming soon but that will definitely be on my list for the future.

[@jordinp2140]

@@JamesMontana Awesome! I look forward to seeing the video. Thanks for the reply!

[@iAmTheSquidThing]

I'd say you probably do need to test these with a dynamic load though, not just a winch. Wobbling them back and forth by hand may be less repeatable, but it is more like the loads they'd experience in reality.

[@kxjx]

It doesn't matter how many bags you use. What matters is that the hole is the correct depth for the height of the post (2ft for an 8ft post) that the hole is the correct diameter (1.5inches larger than the post), and that the hole is correctly filled (fill tightly and top to bottom). If the ground is good and you dig the hole right you likely won't even need a full bag to properly fill the hole and it will be solid. The reason it doesn't matter is that the ground is doing most of the work stopping the post moving; all the concrete is doing is properly packing out the space between the post and the ground.

[@thisguygardens]

thank you

[@R1D9M8B4]

Thank you for the video

[@JamesMontana]

You're welcome

[@massimobarone4624]

Great video.. thanks for sharing

[@bladactania]

I think for either product, the setup could use some work on the post itself. Some kind of horizontal notches, some spikes/rebar extending out of it and a hole that's not smooth as well.

[@llew-AZ]

Glad I watched this before a foam mistake.

[@LawnRight]

All those grunts 🤣🤣 great comparison though!

[@JamesMontana]

Haha its hard work mate. Thanks though 👍

[@danielzee]

I used the foam on a large project, and it's solid, 4 years later. Works very well. But... I wouldn't use the bag type, I used two seperate containers and poured them together, did a quick mix and then poured it into the whole. Filled the hole all the way to the top.

[@iviaverick52]

the foam is a neat idea, but the crucial part about concrete that helps keep posts stationary is the added weight

[@needmoreprivacy4947]

Great video. I made the mistake of setting some posts with that foam crap and of course they all fell down. Don't waste your time it doesn't work!

[@wobber999]

Righty ho I am buying postcrete, Thanks for this video It made my mind up

[@gw1703]

I think i will stick to using postcrete glad i saw this

[@MarcGyverIt]

I did my garden with 6' 4x4 posts in foam. It works well for the line and corner posts, but not for end posts, especially for a gate. NO GO for a gate.

[@lemmuhj]

I used the Sika(foam stuff) to help straighten out a fence that was leaning from a hurricane. The posts were already in cement, but with some ratchet straps and good old fashioned muscle, we straightened it out the best we could and used the foam to fill in the gaps in the post holes caused from the wind. It worked well!

[@mckenziekeith7434]

I set a bunch of posts directly in the earth. I tamped the earth back in around them as I filled in the holes. That was 10 years ago. They are all still fine. So that is another option. But it depends on soil type and wood type. In my case, the posts were all heart redwood. Also, the holes were pretty deep with as much wood below the surface as above.

[@yougonnaeatthat9889]

People are too lazy to tamp in posts. It's a time tested way but this modern instant gratification world doesn't allow for anything that doesn't have an easy button to avoid as much manual labor as possible. Frost heaving is another issue with a straight walled hole, where as a bell shaped hole prevents that. But again more manual labor required to dig a proper hole. Now the world will be dotted with foam plugs, I'm sure that's good for the environment. 😊

[@mckenziekeith7434]

@@yougonnaeatthat9889 I'm too lazy to carry bags of concrete where I need to put the posts! LOL. I definitely don't like the idea of putting foam in the ground on my own property. Wood and earth are very natural materials. Concrete isn't 100 percent natural I guess but I certainly don't mind it. It is environmentally pretty harmless and inert. But foam? I would feel like I was just burying plastic junk in the dirt!

[@oldtimefarmboy617]

@@mckenziekeith7434 If you can rent the equipment. You can get the post you want to install, cut a point on the end, treat the part going into the ground with used motor oil and let it soak in completely, then pound the post into the ground. You do not have to dig holes, the post will spread and compact the soil around its sides, and the used motor oil will waterproof the wood and prevent it from rotting. Oil is biodegradable and the small amount of metal particulates from the engine are too small to hurt anything and the other contaminants are usually soot from combustion and dirt.

[@bobbear4437]

@@mckenziekeith7434 In the US, some electric companies are using foam on their utility poles!

[@yougonnaeatthat9889]

@@oldtimefarmboy617 driving wooden posts in that manner only weakens the wood structure causing faster deterioration.

[@sanchezhandymen3444]

You can also weather proof the bottom of the post before you burry it, or cover it in concrete. This will add a layer of protection and you can not see it as it is buried. A stain with sealer of just latex paint will do.

[@TruWarVet642nd]

So why not just use concrtete all together,...y'all making too much work for such a simple job

[@user-gd1vr1fx8o]

This foam is like the Emporer's new clothes. Set the post in the ground deep enough and there's no need for foam or concrete. Simply compact the soil during the backfilling process and it'll be solid as a rock. It's a centuries-old method which minimises the problem of water collecting around the post and rotting it. Concreting posts in is a relatively modern concept used mainly to save time during construction.

[@Jizden_Mipanz]

The trick i use with concrete is first mixing it in a bucket to proper consistency, i also add a couple 4 inch long x 5/8 inch lag bolts to the bottom of the post. And also filling the hole 2 inches below grade. That way you dont see the concrete when your done and it still enough to hold up to kids climbing the fence. Its a simple process that will save you headaches later

[@theMekanik]

I’m using it to fill the vent dukts from a Sentral Heat and Air Unit Removal. I went with window units.

[@Subie-Driver]

If you live in a climate zone that has winter…you have to pour the concrete so that the top is at least 8 inches below the surface then fill the rest with dirt. If you don’t do that the frost will grab the concrete and heave it up out if the ground. The dirt on top holds it fast against the frost.

[@kwd-2023]

Yup, exactly the mistake I made.

[@clarkpalace]

I d say there might be situations where this fancy foam idea could b useful. What they are is to b seen!

[@jamesbruce1183]

Dry posts help with adhesion. You could add some lag screws to the post to make it harder to pull out. Pour the foam down the sides of the post starting at ground level so it doesn't leave a void around the post.

[@danielnicholas983]

So a right fiddle to use

[@ssssscorpions]

I always stagger a few screws on the sides of the posts, grabs like dead men.

[@The_Tactical_Wook]

Could you use this as the adhesive between multiple sheets of acrylic and polyethylene then shoot it? Like compress it all first to squeeze out excess and keep it from expanding too much then shave off the excess to the shape of a ballistic plate?

[@JeffRiggins8080]

Just this week I installed two fence posts using the foam. It worked great. The foam expanded so much I had to cut a large chunk of it off above ground. Posts are solid 👍. I used an old school post hole digger and dug 2ft deep holes for 8ft 4x4s.

[@bvbxiong5791]

nice try foam AI.

[@JeffRiggins8080]

@@bvbxiong5791 WTF does that mean?

[@krevor4095]

@@JeffRiggins8080 I think he's accusing you of being a bot? (Seems jokingly, but I'm talking out my back side anyways, so..... lol)

[@JeffRiggins8080]

@@krevor4095 I've been accused of many things, but that's a first 🙂.

[@f.demascio1857]

Ill go tell the 35 posts i set in foam that despite their 2' deep bell shaped holes, they are standing in defiance of your superior knowledge amd they all need to fall down already. Thanks

[@barney992]

could put a metal or treated wood cleat nailed to side of post under ground level to support it . Also stops it lifting out of concrete .

[@brakel8r]

The society of immediate results has brought us to this. these are the same people that believe a bathroom re-do should only cost ya $2500 US

[@travismoore7849]

I wonder if you could put that foam in a mold to make foam panels or bricks?

[@bm7760]

My fence / gateposts are all rotting out at ground level. The house has been there fifteen years or so. Interested in the pea gravel idea mentioned in the comments (quite a lot of rain where I live). Is there anything you could do to the bottom of the post that'd help it grip? What if I put stainless nails or some such into it before dropping it down the hole? I ask this as a home DIY guy. I'm not a tradie. Thanks.

[@turbodog99]

Packed dirt also compresses the sides of the hole

[@dano5663]

Good assessment but the main problem with concrete is that your wooden posts will only last for 6 years because the lime in the concrete will rot the post off where the concrete meets the post on top. You may achieve a little more longevity with angling the mix downwards and away from the post but concrete and wood are not a good in-ground mix. I haven't used expanding foam but since it is used to secure window frames into buildings and provide water seal, it may be a worthy option. Personally I use broken brick and block (good for recycling) with soil and they have been carrying 2 x 5 bar gates, I do however apply several coats of expensive wood treatment. I have posts many years old that don't need replacing! The other thing is that you have a lot of work on digging out and disposing of old concrete, when the posts have gone! Tried that one - never again! For field posts and wire fence I don't use either just a hole and a narrow spade. That works okay.

[@archieanderson2945]

Thanks for the review I know now that I will be using Concrete mix. I noticed you did not mix the concrete Can you please elaborate I have always been i the habit of mixing in a wheelbarrow. thanks for sharing.

[@derekparent752]

I would like you to dig up the concrete for the one post, I am curious to see how well the concrete mixed in the hole without actually mixing it.

[@durkkush8802]

it didn't, that is why he could pull it out by rocking it back and forth.

[@chrisyoung9653]

its ready mixed. just add water

[@durkkush8802]

@@chrisyoung9653 do you really think the bottom, say 4"-6" was mixed properly and hard? I don't and it's from experience.

[@chrisyoung9653]

@@durkkush8802 ive been doing fencing for 12 years man. never had a problem with it yet. i always use lafarge or blue circle and its great.

[@chrisyoung9653]

@@durkkush8802 if the bottom didnt set right you probably didnt use enough water

[@lovemussb1940]

Trouble is expanding foam deteriorates very quickly outside.add sitting in sopping water to and fence posts begin to rot. When putting in cement rub it up the sides of the post to 200 mm above ground level and they will not rot.

[@01sapphireGTS]

Nice test. I'm never even trying the foam.

[@rampartranger7749]

Ouch, we have very high winds on the High Plaines of Colorado, 60 mph winds every single year, sometimes. 70-80 mph gusts

[@specialservicesequipment393]

The power line contractors set the power poles with the expanding foam.

[@JH-lc8xd]

I have never seen the brand you used in this video. My local hardware sells anchor foam that comes in a can like great stuff foam insulation. Its a snap to use. Sets quick, dries rock hard, and excess can be cut away. Its rated for load bearing and non load bearing use.

[@SplittinWigsGaming]

The foam I used had me pour it different and I was also supposed to cover it with first once it got to a certain height so it would adhere to the post and into the ground.

[@chrisfox3637]

This stuff actually works very well when used correctly and keeps the post from rotting. The only downside is it takes at least 1.5 bags per post not one and sometimes two. I also go 2.5-3 ft deep because of the 8ft height. I have over 1000 foot of 8ft tall wooden fence built with this and it’s very solid. You have to fill the entire hole and saw off the over fill after it hardens. Then come back and cover that with dirt. Once everything settles it’s solid as a rock. Before I committed to this product I installed 3 post with it and waited a year before actually building it to make sure it would work on this size of a job. I tried everything I could to push the post over by hand and couldn’t move it at all. I would definitely use this again instead of concrete because concrete keeps the post wet. Redo this video with this way of installation and you’ll change your mind about it

[@flhusa1]

With the foam i would make a weight to sit on top of the foam before its done expanding to force it to expand outwards in stead of up.

[@jameshill8731]

Foam in the ground sounds great for the environment.

[@mustlovedogs272]

Whichever you use, hammering several 4" nails two inches into the post, 2 on each side so 8 total, prior to the concrete pour, makes a hell of a difference.

[@emotionz3]

Used the foam when I build my kids playhouse and the thing has become more and more wobbly over the years. Makes me wonder if the foam is shrinking or water is deteriorating the wood posts below grade. Initially it was very solid, easily as solid as concrete. Kind of disappointed but hey at least it will be easy to remove someday when they outgrow it lol

[@stebbarry9395]

How much difference do you think it would have made if you had filled the foam hole with a second bag or topped it off?

[@Tekagi]

He should have read the handy chart that's plainly visible on the bag. You only need one bag when using a 4x4 post for a 3 foot deep hole that's 8 inches in diameter. If the hole is 10 inches or bigger in diameter, you're supposed to use two. The hole in the video is obviously 10-12 inches in diameter, so he messed up and this video is next to worthless.

[@philipwilkins3812]

Looks ok for a line post. I don’t think I’d trust it for anything that has much stress on it.

[@christiantan1432]

I used SIKA on all the posts for my entire fence!! Had severe weather pass through already and its been solid!! Now come 15-20 years when I need to renew the fence, it should be an easier job pulling the old posts and augering the same spot and refilling it with new sika! 👍🏼😄

[@SEBTECHDIY]

Good point!

[@jeffreymoen1440]

I have used the foam. I set a mailbox post using foam about 4 years ago. Still solid. Not sure what you did wrong but be fair and try again.

[@paulstarnes3112]

Center of gravity, and 100 lbs added to cement post. The soil density is the weak link. In US all power poles are anchored with foam with no issues.

[@bryanmontgomery4050]

Wet hole, plastic bag over post, pour foam between post and bag, it will expand and push the water out of the hole without causing an issue with the foam..

[@michaelcatalanottohandyman]

This only confirms my suspicions of concrete is better.

[@starpartyguy5605]

I built a 6 foot fence with 4x4 posts. I bought orange post sleeves from Home Depot. I have 1 left for when my mailbox gets hit by the next careless snow plow driver (LOL). I drilled an 8 inch hole. Put 25 lbs. of crushed stone in the bottom for drainage. I slipped the post protector over the post. It has an air gap all around the post for drainage. I put one screw in it to hold it while slipping it in. Then I filled with two 90 pound bags of concrete. I used 7 posts. All totaled, that's 1400 pounds of concrete holding down that fence. If it gets hit by a tornado, the house might blow away. But that fence will still be there!

[@HiwasseeRiver]

Reading the comments makes me wonder if there is a soil temperature effect - some US users report good results. I wonder if warmer soil or use in a warmer season impacts the results of the foam. I would definitely do a single foam test before going all in.

[@johnpipping3848]

Normal concrete mix well tamped into the hole. Cheap and reliable.

[@johndodson8464]

Next, test foam boat anchors vs. concrete ones.