Concrete block DIY Storm Shelter 12x20 foot 

My friend. I am proud of you. The man has to do for his family, what he has to do and you did it very well. God bless you.

You say you aren't an engineer, so you didn't build it like an engineer though you built it like a boss :) Good job.

Imagine my surprise when I found out it would cost $10 to get more info. I don’t think so when there are several mistakes he made in the build. First if some one lives in earthquake areas, the rebar needs to be bent to go up into the wall, tying it in to the wall. You also need to have “L” shaped rebar from the wait into the top. And it wouldn’t hurt to put rebar vertically through the wall blocks themselves to hold the walls together. Sure it adds money, but keeping the walls together would save lives. Another even bigger mistake is not using sand in the concrete if you mix it yourself. Sand is what holds the cement mix together. I haven’t read all the former comments, but it seeks other people thought it was wrong for you to charge $14. After all, you could literally be saving life’s with the info.

My experience: In CT I built a house with walls 8" thick and reinforced with rebar ONLY at the corners The walls sat on massive footings, the grade dropped 8' away from the house and the downspouts were led through 6" solid schedule 40 pipe to "the light". The foundation had weeper drains with perforated 4" schedule 40 pipe set on clean gravel, covered with silt cloth followed by 2' of pea stone and then back filled. House #2 in OH was built with block, otherwise the same. The foundations were waterproofed on the outside and painted with two coats of Ultra DryLok on the inside followed by 2 coats of highly reflective white paint on the inside. Worked very well, except OH, when we got the storm of the century - 8" in one week followed by 7" in less than 60 minutes! I went from one very dry basement to 2' of water in 17 minutes! The water came in the basement windows so fast that it moved a 5 gal. bucket of horseshoes and stakes 76'. House #3 in OH is built of poured concrete 8" thick, reinforced with rebar and has a brick pattern on both sides (steel forms). The outside was sprayed with one of those new rubberized compounds, covered with a fiberglass mesh, sprayed again and then insulated with rigid 4" Styrofoam on the outside only. By law, OH requires sump pumps. I have two with the second water powered. The basement stays warm and dry all year.

80 bucks a yard for concrete is 1983 pricing

I live in California. The way you built this shelter is a death trap. Any lateral movement and it will collapse. You need rebar every 32" bent up out of the slab and into the blocks with vertical rebar continuing up and bent into the roof concrete. Horizontal rebar every other row wired to the verticals making a rebar box encased inside the concrete . The block would have to be 100% fill with a pea gravel mix. and don't tell me it can't happen in the Midwest, there was a 5.0 last week in Kansas. The largest earthquake ever recorded was in the boot area of Missouri. Your type of structure is why buildings collapse in Mexico and elsewhere.

To handle the extra concrete that will be left over, make some forms for sidewalks, planters, etc. where you can use the surplus. You can make the sidewalk forms like a box which will give you a smooth bottom and a top. Be sure to place rebar in it to keep it from breaking. You can make them at different lengths and use them as paving stones later.

For someone who never did mason work before, you really did your homework and a great job. I am thinking of a small shelter myself. I do not need the size you have but you gave me great tips.

Oh, and rebar should be sticking out of the foundation to anchor the walls . fill the cavity of the block where the rebar runs up the walls. allow enough rebar to anchor the roof slab too. Just saying...

A 2X4 will fly right through a concrete block. If you fill the blocks with mortar first it will be safer. The best thing to do is to pour the walls of solid reinforced concrete.

Best way is all cast in place, reinforced structural concrete. In my past consulting business I detailed formwork drawings for many small town tornado shelters in Arkansas. Most were high school gymnasium sized structures with design engineered specs and drawings that would have multiple usage beneficial value. Those structures were totally above grade. Block masonry is more cost efficient but should be designed and constructed only by qualified professionals. Tornadoes vary in their wind velocity and safe shelters should always be built per applicable codes and specs! Shoring the elevated cip roof slab and the decentering ie extremely critical in releasing the properly cured slab to assume it's own load. If decentering process is not done correctly the whole roof slab could possibly and catastrophically collapse!! This is always critical on elevated floor slabs and cip slab and beam bridge structures. Use of a licensed structural engineer will also spec the rebar and the mix design specs for the whole project. An architect can also help you.

Fiber glass fibers (less than 1" long?) are the bomb. I put them into the mortar mix used to coat a cement block wall, both sides, one coat and 9 years later there is not a crack anywhere. You can't find one looking carefully. The cost of the whole 200' of 4 1/2 foot high wall was half a $18 box.

This is EXACTLY what I have envisioned for me and just started my research. Thank you. THANK YOU. You saved me so much work and have given me great encouragement.

Great video I'm in the process of starting my shelter and I've done all the research you've mentioned. Yet still learned alot thank you 😊

I'm not an expert builder but I am expert in getting people to watch part of a video and paying to watch the rest.

Save money building your shelter by buying up all the torn open bags of sand, peat gravel, cement, etc at your local building supply if you have a dry place to store it. Just mix all that crap together and pour it into forms with some rebar. Just make sure the roof is well supported and don't skimp on cement then as you need a roof that can stand the test of time.I'd suggest an arched roof as they are fairly simple to do, and safer. The torn open bags are usually about 70% off, just have a good method of getting it home and into storage intact, and check back every week. They end up throwing most of it out as nobody wants to bother with it.

You're not an expert, you had no experience prior to building this, but you want us to pay for your video? This is all information you learned just from online research, which anyone can do for free. I don't mind watching it on your website so you get the ad revenue... $14 bucks to learn from an amateur though?

That was a nice gift from your fellow Church member. $300 for an 8 hour day including a backhoe. WOW!!!! You must be good friends.

You realize that if you just post the whole video on here instead of charging $14, you'd probably made more via Google AdSense or whatever right?

This popped up in my YT feed following the recent December 2021 storms. Thanks!

I've found some problems in this video. 1. First of all, if you live in a place like Moore Oklahoma we get a lot of floods, and building it in dirt makes it even worse and makes the storm shelter easy to pop out. 2.Do more research about tornadoes, you gotta know rather or not strong tornadoes hit that area often, even if it doesn't than you still gotta be safe from a tornado because after a few years of the tornadoes hitting the storm shelter it's going to pluck out of the ground and killed a women who was in her storm shelter during the Bridge Creek tornado this year because of floods. 3.If you're going to make a storm shelter, make a car port if you don't have a garage, that helped me during the May 6th 2015 outbreak where there was flash flood emergencies issued a lot.

8 minutes I'll never get back!

$14 for the video and plans is very reasonable in my opinion. The amount of research and time designing, and learning from mistakes is easily worth that. Knowing what not to do is sometimes as important as knowing what to do!

Plenty of haters here for some reason but for 3k, not bad. Thanks for the info

Everything you talk about for concrete and block specs I learned about over 35 yrs ago in my Brick Layers course , with building a storm shelter like that , and pouring concrete , you also need to have proper forms (oiled type forms are only used ) and proper type of reinforcing steel . Ordinary rebar is not acceptable , must be coated or use Stainless Steel wire mats (4x8) or wire mess that has a coating not to allow rust to start, unfortunately less expensive products are available and used due to trying do it on the cheap. With over 38 years in construction industry from being Certified Bricklayer and Stone Mason , Certified as well for Blue Prints to Class 3 Tandem driver with 17 Ton cable Crane credentials , several flaws as well in your construction . Never build on side of a bank , Hydrostatic Pressure on 3 sides will cause Subsidence or moving of the structure for storm shelter , must be backfilled on all 4 sides and tamped the earth every 2 feet as well with Class A Gravels , redish clay or clay type soils for back fill allow for freeze thaw cycles , even with mildest winter climates, frost can occur at the most unforscene times , climates change without notice . Using Aggregate mixed type soils and tamped also allows for drainage away from structure and you also never used any drainage conduit around the structure , mould will occur even in block type structures without notice and the air will become stagnant and toxic . As I say I'm certified now 36 years and have built several these type structures of the same . Research is only small part , lits if wrong info as well on the internet . As for Engineers , well I'll leave it at that , they all have thier own versions of how it should be done , most could not mix cement in a wheel barrow. I might ad as well Today I work for a Brick and Block Manufacture , and filling the cores you must also vibrate the Concreate in order for proper Airation of it for proper and full PSI set up , not doing so can cause premature failure if the block due to inner hydrostatic pressures during cure time , I've seen several walls fail for lack of proper Airation of pouring Cement into cores and try to blame the block products , when in fact short cuts were taken

I thought this was really a DIY video, not a nine minute commercial for a video you're selling. Thumbs down!

Wonderful presentation. Thanks. 👍🏽👍🏽👍🏽❤️❤️❤️

I can’t believe this but I’m considering heading over to your website and paying.

You built a shelter-shaped object. I could tell you at least five mistakes you made, but will require payment of $14 first.

He must not. Break it into parts. Everyone wins. Love your comment. I would never give him 14 bucks but I would watch and re-watch them to learn more. Good call

I don't mean to "troll" your video...but why pay for the full length when this information is available for free with a little bit of a Google or RU-vid search.

I witnessed a buch of mistakes, 1 the block was dry when you were laying it, 2 the ground was not tamped 3, the slump of the concrete looked off.

That is some thin form board!! And not compacting your soil and then not using gravel under the concrete for drainage is a major no-no.

Re-bar shouldn't be attached at 90 degrees, 180 degrees only. That's why the shape, it interlocks when encapsulated by concrete but held tightly together with wire, it can't slip. For a corner, bend a piece about 3' long to 90 degrees, and put one in each corner. Attach straight pieces to it. The re-bar shouldn't be rusty. Near salt air it's usually painted for that reason. Each gage # is 1/8" so a #4 is 4/8" inches or 1/2". # 5 is 5/8th etc.. I didn't know about the water and weight thing. We would have a short path, some patio stones formed or anything, to accept any excess concrete from our estimate.

Well Done!! A 20 ft Diameter dome would accomplish the same goal and actually give you space for 30 people. I believe that structurally it would offer more protection in the event of high winds also. BEST

You could buy this guy's (who has no experience) video or you could just go to FEMA's website and download plans for a storm shelter (devised and tested by experts) for free.

If it's above ground it would have to be anchored pretty deep and I think every hole in the cinder blocks should have anchored rebar going from the slab all the way up to the roof and filled with concrete.

I learned everything I need to know by reading the comments! :)

So you tell us not to go with your advice but you're selling it 😂😂

Lot of very good information and you talked instead of playing weird music thank you and I didn't know the water in concrete stayed there that never occurred to me thank you for this video

Wow Dave, these u-tubers can be brutal, well done research and hope all works out well for you and your family!

as far as water proofing I'm going to use Ame's Blue Max, and for the bottom of the slab I will put down Black Visqueen . You just Roll The Blue Max on with a paint roller and you have water tight walls and roof!

The amount of detail shared regarding the options assessed, decisions made, components selected and rational thereof, as just outstanding - great info and many thanks for sharing!

I still learned from this video so thank you.

Big neg for you, I wish I would have read the comments before watching your video.

the one thing you missed was tie of corners and tie of base to the blocks... and then there is the water soak issue on cinderblock.. and no rebar in the blocks... as well as roof tie to the walls.. things move and shift on these projects over time... also dome the top up a bit in the center for more strength... one of the cool things I have seen was the use of spray bed liner material to coat the inside of the blocks.. pain to deal with... but would be super nice if it would work for the outside of the slab and walls as well as the roof outside... some have tried membrane under the slabs... it works but mice and rodents can make a mess out of it!! hard to vent these if they sub grade level... you did well building in a bank... good for storms... make sure you have a good door that opens in that can never be blocked with trash from a storm.... this style is better for tornado shelter!!

Informative and concise. Thank you for taking the time to make this video and sharing it.

Well done, good sir, WELL DONE.!.!.! And you say that you aren't an engineer.. BAH, you sure researched it like one.!.!.!.! Gratz on the build.!.!.!

In Warfare “A good plan, violently executed now, is better than a perfect plan next week.” ~Gen. George S. Patton.~

Oh, and we must be the only places (Oregon and Wash. St.) That pay close to $3.00 per concrete block! Everything here is higher priced.

I think I'd take my $14.00 and buy a bus ticket to someplace where didn't have tornadoes.

So 8 years later are you still trying to sell it or do you want to let us watch it on your site with adds?

You should have been up front on what this video was and what it wasn't. It wasn't a video about a storm shelter, it was a video about selling a video.

WOW! your talking my language. this is the best video I have seen for what I was looking for & looking to do. THANK YOU! It saved me lots of research time!

some of the ppl commenting need to take a breather. i don't know if he is missing any critical design points because he is not a "pro" but depending on the price, the info cd could be a useful introduction at least to the concepts involved. sometimes the "pros" are not that good at explaining what you want to understand when you build one of these or have one built, and you benefit from the perspective of a another "layperson" who went through the process. the info cd can be a starting point just for education, or if you choose you can follow the design, but it's nothing to lash out about.

At first glance it looks like you put it too low below the bottom of hillside. The hillside is the best place for it and never straight down into level ground...but the bottom of the concrete floor pour should be at least 1 foot higher than the level ground at the bottom of the hill, with a bed of crushed stone and perf pipe underneath. I did not view your entire video on your site but I hope you put a lot of crushed stone and perforated pipes around the back and side walls of this. The hillside is the best place for this as you have a place to gravity the water, but the #1 thing about building this...especially with concrete block, is drainage.

Ive heard the best way to keep a storm shelter or bunk clean is to use it as a clubhouse/hangout space. Spiders and bugs are found and removed before there are to many and you get to use it the rest of the time for fun.

Wow…very ambitious and impressive…10 Yrs later, how well has it held up? As it is now March 2022…thank-you.

Leftover concrete can be poured as a pathway.

I am not an engineer... Or an expert ! Therefore when my family drowns in the structure I built... IT'S NOT MY FAULT ! Or gets impaled by flying objects ! Or gets sucked out ! Or ? Or ? Or ? HOW EVER LOOKS GREAT ! AND NOW I WANT ONE TOO ! THANKS FOR THE IDEAS & VISUALS !

This video started out great, but pissed me of because it only showed a piece of the Storm Shelter build and when you go to his website to watch the rest of the video, he wants you to pay for it!

Should have put rebar in the slab pointing upwards so your walls would have more support.

@David: You have done an awesome job sir. Cheers

It's a great video. well done. I would like to see more....but I won't pay for it. at any rate....I appreciate this one.

A great help for a project like this would be by using Mortar Joint Spacers. The Spacers enable the DIY'er to lay Block like a PRO!

This is awesome thanks for sharing the process and you experience level before you started

At the base of the structure or part of the footings there need to be about a 2' horizontal concrete extension all around. This provides an anchor for the buried structure from floating and lifting during high water table events. Trust me when I tell you that your shelter will pop up out of the ground if given the chance!

Wow. Great job on the video, very informative 👍🏼👍🏼

your not a pro , but you want me to buy your video ?

The only possible issue I can see with your design is I believe FEMA and Texas Tech recommends that with concrete block construction you fill the cavities with concrete and possibly reinforce with rebar. Did you do anything like that?

I think its pretty sorry of you to charge people on your website for the full video. Knowledge of something like this should be something you would want to share with people for no other reason than it might save their life and the lives of their family and neighbors in the event of an emergency. Knowledge is power and should be free to all that seek it. Any good deed that at its core is tainted by the lust for money is no longer a good deed.

Have you considered volcanic ash, lime, water, and agragate as opposed to portland cement? Its closer to roman concrete, hardens more as it ages, and is naturally waterproof.

Title should read "Advertisement/Teaser for DIY Storm Shelter 12x20ft."

Nice work Bruh. Well laid out and user friendly. I'm sure you'll recoup the cost of your shelter plus a some extra.

I have worked for a concrete company for 10 years so I feel it necessary to advise that 3/4" plywood is not a good option for the form on the slab. Use a 2x8 or Form-A-Drain for a form and go to your local building materials store and buy steel stakes a $2.99 a piece. Finally, place your stakes 3-4ft. apart and drive your stakes so that it does not stick up past the top of the form board as you will use the top of the form to set your strike board so that you can even out the concrete.

This is a sales pitch for plans. So do what you like with that.

Let this be a lesson to all. People hate a money grab.

It never ceases to amaze me how Americans are always trying to work out how to make a buck! Having said that, this guy is 'saving' you the time and effort of having to work out all the details, by providing all the information he spent a LOT of time gathering, into a single package you can download for $$$. If you don't consider YOUR time is worth anything ... don't buy it!!

using regular rakes in concrete can leave week spots ..it pull the rocks separates it from the mix ..very nice structure ...

Hollow cement bricks. Should have poured them full of concrete. In Arizona. Monsoon seasons blow's over brick walls all the time

You forgot to pitch the floor and add a sump with a sump pump for condensation removal . You should have put a french drain to take table water away from the box

So you just made a video on how to create a death trap.

Block companies must have seen this video. Blocks are now 2.25 ea in Tn.

This is the first time ever where someone was going to charge $14 to watch the rest of the video.

Nice shelter Dave.

Good video. I like laying concrete it becomes addictive. ;) How you go about things reminds me of how I approach my projects.

I have done a lot of concrete work and this design would never have even passed plan review in my community. perimeter drains are mandated, with gravel backfill above but outside of block wall must also be waterproofed I like spraying with asphaltum and covering with visqueen before backfilling. In a retaining wall at least two rebar go in the footer below the frost line and a vertical rebar goes up thru the blocks and that cell must be filled with mortar no more than 12 feet apart. The roof needs more steel than you included in your plan and I did not see an engineers certification. Did you have a building permit? What about plumbing and electricity? Is space certified for living space? why not use a arch or dome for greater strength in the roof. Or use prefab "Hoot-eyes" for the roof they are available eight feet wide and 30 feet long and only need supported on the ends. Pour the floor separately and last after the plumbing goes in. I will remember you in my prayers as the next tornado may be your last . You leave out too much I suspect this would only be permitted as a farm equipment shed, not for human habitation...

You can't always get what you want But if you try sometime you just might find You get what you need

He did the right thing by using a vertical door that opens IN. Anything else can be a tomb when you cant get out afterward.

In response to Botkin's response (since you're asking, not him): I've seen vids on how to reenforce the sides and ceiling with I-beams, plus if you don't have a foot of dirt on the top, the weight shouldn't be a huge problem. The outside can be painted with tar, put a foot or so of gravel on the floor of your hole, and fill the sides in with gravel. This is also free info, for everyone but Botkin - don't read this unless you pay me $9 first.

You may want to provide drainage from behind each wall much as you would a retaining wall.

Nicely made video.

I think there are quite few mistakes like: The gravel bed is not thick enough, not compacted. Those blocks, I believe, are meant to be filled with concrete, not cemented together like bricks, they don't have enough surface for that. There are more things. But overall, I'd say "good job" for someone doing his first concrete build. Maybe it's a kind of a build, where it's OK to do some mistakes. It will still withstand a storm or F4 tornado, I guess.

You could have gotten a box culvert. Minimal preparation needed - just dig a hole, some basic preparation, and then you just have it delivered and put in place

you are teaching us how to build a regular house in middle east

Thank you for the information.

at the time i constructed my full basement the decision was to get full pour of concrete for my walls. at that specific time pour was cheaper than block. We know now that my 4 trucks had the wrong mix it had pea gravel river-rock. with all that rebar and the way it was constructed it stood against a f4 tornado that left my town with 11 dead.

Great grow room thanks!

Thank goodness I have a full size concrete basement.

haha imagine this my grandparents had a 16x25 built back in the 80's i think, they literally did'nt have to pay for the hole to be dug and all the forms set up the crazy ass neighbor down the street hes like "i'll do it for free all you have to do is supply me with beer" hah my grandma still bitches about it today having a drunk guy digging a hole in her back yard with heavy machinery. btw the shelter is still in perfect condition today has a 350lb steel door we had to get hydraulic shocks and if debris was to fall on it the hydraulic powered door will come right open.