Cinderblock pool walls?

[cwalker1960]

Seems many are looking for ways to save money building their own pool. Building the walls with concrete block certainly is an option. As mentioned further back filling the block is a must to ensure that the block don't move and cause cracks in the plaster. 1 # 3 or # 4 rebar per block cavity will be sufficient before filling the block with concrete. A regular 3000 psi block fill concrete mix will be fine for filling. Another choice to save money is to hire the subcontractors yourself. Many pool companies use sub contractors to spray the shotcrete for the pool shell. The subs aren't the ones overcharging, it's the pool companies/contractors. By using shotcrete you have unlimited options for shape, steps, benches, swimouts and ledges. By time you figure the cost in block, laying them, the concrete to fill them, and all the labor involved, you may find that hiring a shotcrete subcontractor affordable. It will cerrtainly make your job a lot easier. For more information check outhttp://howtobuildaningroundpool.com/

[patrickspools]

I work on liner pools made from cinder block all the time. They are not even filled with anything. These pools are ancient and have no problems. I even just chisselled a hole out through one for a light.....no problem. I also have a customer that dusted over his and it did not crack for about 10 years. I don't know if his blocks were filled....knowing him they probably were

[kenected]

Hey I am not alone! I just started my cinder block pool that will have a Jacuzzi, 3 water falls, and a grotto. The way I am building mine is this: I dug the hole and squared it off at the bottom and wall connection. Then I dug a 12" x 12" footing for the walls. I used a lateral 1/2" rebar with 1/2" vertical rebar in the footing. Verticals are in every cell of the cinder block. I poured a continuous footing setting first course into footing level with step ups as needed for design. Then every other block I ran rebar across the bottom of the pool up into the side walls. I then stacked 3 courses of block and ran horizontal rebar 1/2" wire tying it to the verticals (rebar). That is as far as I have gotten so far, still working on walls. Will keep you posted!

[Kwanders]

I am planing to build a Lap pool...8' by 15'. I want to build it about 5' deep. 2' underground and 3' above ground using 8" by 8" by 16" Questions... If I place durawall at each course above ground. Will my wall be strong enough to stand up againest presure of the water.... And can I tile the cinder block?

[cwalker1960]

Not filling the block is fine if you plan on putting in a vinyl liner. This is not acceptable if the pool is to be plastered. Plaster doesn't give, it cracks.
As for pouring a footer , laying the block walls then pouring the floor,, if you're planning on plastering this pool , it wouldn't be the way I would go about it. Footers can settle , then you have a leak around the perimeter of the pool. With the footer dug as you have described , tie all the steel in the floor and pour the footer and floor at one time ,, then lay the block. We pour floors on big commercial pools all the time ,, I'm talking 70' by 150' by 17' deep. and this is how we do it. I have seen pools with the floor poured later and they leak period.
For the one wanting the pool "x" feet out of the ground. i can't remember your dimensions , but water pressure ca be quite substantial. Straight walls don't have any support built in. it would most assuredly be worth your time to get an engineer to look it over before proceeding.
And I have said this before on this forum . People , get an estimate from a shotcrete company before you spend all this time and energy. You may very well find out that it is cheaper and much faster in the long run to hire this part out.
This information is not coming from someone trying to take your money . i seriously doubt that I would be the one shooting the pool for you anyhow unless you happen to live in SC. just trust me on this , I'm trying to help. For more help visit how to buildan ingroundpool

[cwalker1960]

Okay the 8' x 15' out the ground 3 ' If you pour the block full, I'm sure you'll be fine . If you really want to be sure put bond reinforcement wire in every few courses.
And it's none of my business, to each his own, but why are building a 15' long lap pool? practice turnarounds? Don't kick off too hard. On the other hand though , you could install a badu jet and get in some decent swimming.
About the shotcrete/gunite thing. i know all of you have already found out that a gunite pool costs a gazillion dollars. pool contractors typically mark their pools up 50 to 100 %. that means a pool they gave you a price of $30,000.00 for cost them 15 to 20 thousand to build.WOW!! what a markup. There really is a reason behind this madness.
As a business they have to realize that there is a potential for something to go extremely wrong. So essentially they are getting enough money to build every pool twice.
The shotdcete guys aren't the ones getting rich here , and if you take a few moments to do the numbers i do believe you will find it worth your time to sub this part out. Not to mention the fact that by using shotcrete instead of block you can have your pool any shape your heart desires and benches where ever and steps any shape or size. I'ts truly amazing.
You're not going to use much more steel, probably not a whole lot more concrete, it's done in one day , yep floor walls benches steps spa , everything , over with ,, Yes the shotcrete material is a little more expensive than deck mix ,, but you still have to fill those block and that's pump mix , oops , and you probably want to hire a pump any how to pump the block walls full unless you're planning on using bag mix , which will work out to be considerably higher than pump mix. probably could have hired that pump.
Block isn't old school because we are trying to take your money , it's old school because there are better faster more practical ways to do the job. . for more help and information

[shrek12]

hi do the block walls need to have some sort of waterproofing done to them before plastering them.
thanks

solid concrete bottom and filled block walls

I think this is the key. Unfilled cinderblock will result in cracking over time and may not provide the absolute durability/ rigidity a pool requires.

[txkiwi]

I'm also about to start a DIY concrete block pool (solid poured). Vinyl liners seem to be the way to go vs. plastered finish. My last question before moving on this is what structural engineering is required for getting a building permit? (7-8 courses on blocks). I see I can by standard structurals for shotcrete pools, but does anyone have similar engineering details for cinder block pools?

[niaco1]

I have the same problem, did you find out how to fix

40 Year Old Pool,
We moved into a house where the previous owners did just as your dad did. Ours is still in great shape too!

Last year we had a hole in the liner (and didnt know it then). We thought there was a leak in the main drain, thanks to a local pool company. We removed our liner with no chance of putting it back in. When we removed the liner, we have found that there are two or three blocks that have moved away from the wall.

Have you ever had to "push" a block or two back in place? They are out approx 1-1/2 inches. How can you fix this?

Also, what do you use to "paint the pool"? Im getting tired of the expensive liners every five years or so. Have to buy one this year since we destroyed ours last year.

Thanks!!

[Jax]

I don't see too much sucess in home build stories, but I will keep checking back. I plan on building a large hot tub with formed and reinforced concrete. Looks doable to me. And this site looks like it can offer plenty of suggestions on care and maitaince as maybe some suggestions on building too.

[kenected]

cwalker thanks for the recommendation on my cinder block pool. I would say that you are right to pour floor & wall footing at same time. I just am finishing the plumbing now and am ready to start the pour. I also will be setting my starter course into the footing to prevent cracking at that area. I started with 1/2" rebar but was told to use 3/8". I also was told that the shotcrete guys use only 3/8" with a 1' x 1' grid pattern. Any thoughts on this?
Thank You

[Xclusive]

I started with 1/2" rebar but was told to use 3/8". I also was told that the shotcrete guys use only 3/8" with a 1' x 1' grid pattern. Any thoughts on this?
Thank You

Sorry for chiming in but your project looks interesting I figured I could answer this question. The main reason 3/8" is used is because it's strong enough but yet it can be easily bent and shaped at the same time. But i see no issue with you using 1/2" if you can manage to achieve the shape you want for your project. As far as the grid pattern I would definately stick to 1'x1' since it gives you the correct density for strenght.

cwalker correct me if i'm wrong!

[41 year old pool]

Update: pool is now 41 years old , this year it required a minor repair down to the block level (apparent cause was a gap in the poured concrete that did not completely fill one block - so be careful you get the blocks completely filled) but other than that just normal spring opening procedure as outlined above.

Attached pictures are from 2009.

pool1.jpg (148.78 KiB) Viewed 28451 times

pool3.jpg (129.7 KiB) Viewed 28432 times

I have never seen any problems with popped blocks or cracking in the plaster as mentioned in some other posts. This seems to be a reliable and durable method of pool construction, 41 years and counting.

The following is not a problem with the pool itself but with the surrounding deck - if you look closely you will see that the flagstone deck has settled around the pool, this would be avoided by ensuring complete separation of the deck built on the pool wall from the surrounding deck area + use a proper depth of tamped stone-dust as a base for the surrounding deck.

Also should have mentioned previously - if you live in a high water table area be sure to include a pressure relief valve in the drain hole - this will allow any water present under the pool to flow in when pool is empty, avoiding possible buckling of the floor. As an aside - the floor of this pool is still in in great shape.

Apologies for lengthy posts - I hope they have helped you with your decisions / plans.

[cwalker1960]

# 3 or 3/8 rebar is pretty much the standard for residential pools , Occasionally 1/2 " is used on some of the larger commercial pools . 12" grids are fine , if the pool is over 6' in the deep end we put transition bars down the shallow break to about half way up the wall in the deep end to create 6" x 12" grids.. Just a little insurance that the break or the deep end floor doesn't crack.

As for the other members question, no waterproofing is required prior to plastering, The plaster is the waterproofing. Bond coating is recommended if there is any question as to whether or not the plaster will bond properly.

and lastly , I wasn't trying to talk down concrete block pools , If you're up for the work it is doable method to build a pool and properly constructed, should last for many years. I just don't see the huge savings in it myself.

[legendarybear]

i am also attemptimg to do an inground pool with blocks this summer. it is surely a reliable way to construct a pool. i am still in the research steps myself, but i have some things to think about. one being your plumbing and electrical. drilling through filled blocks and rebar is a nightmare, so it is crucial i think to get all your plumbing and fixtures in before you fill the blocks. another thing is your backfill process. to relieve stress on your walls it may be a good idea to have your pool ready for water prior to backfilling the dirt. this gives you an opportunity to test all your plumbing and electrical before it is covered up. also you are able to fill the pool as you fill in the dirt allowing an even pressure to both sides of your walls. this will relieve stress on the walls. as i go further in my project i will update my progress. best of luck in your projects

I was wonderiing if you finished this project and how did it turn out. Would like to see some pictures if possible. I am fixing to take on this challenge and would love to know what not to do. Thanks for taking your time to reply