Posted By slenzen

First of all, ICFs probably will never have the torsional and shear stability needed for pool walls; there is just too much weight and too much hydraulic pressure for ICF's to be effective. (For example, the average pool weighs 28 times more than a housing structure of similar dimensions!)

They are reasonably effective when used as "building" building materials, but are (in my opinion) unsuitable for pool construction when they are the only structural element in the pool wall.

I would try to find a structural engineer with a hydraulics background and see what he says.

???   The ICF is only the formwork, inside which is the steel and concrete which provides the strength. Your comment implies that the ICF IS the structural element, or am I missing something?

Why not use traditional, removable concrete forms? Drop some EPS into the exterior side of the form if you want some insulation. This leaves you without the problem of a soft surface on the interior side.

There are methods available to protect the foam on the inside, with the EPS on the outside only you are not achieving the full benefits of ICF such as ease of heating the pool, extending your pool season and reducing your energy costs of running the pool.

My pool is 50 years old, it's concrete and costs over $ 1,000.00 for 4-5 months of use, an ICF pool can get 5-6 months use and I am told the cost to heat is under $ 200.00 for the season. I'm in Canada. I opened my pool May 15th, the heater ran pretty consistent for 3 days, heating the water was easy, it was heating the surrounding ground that took so long and cost so much, I figured that alone was $ 60.00. I believe our natural ground temperature 4' below grade is 48f.

with the EPS on the outside only you are not achieving the full benefits of ICF such as ease of heating the pool, extending your pool season and reducing your energy costs of running the pool.

Insulation is good, but inside, outside or both makes basically no difference. Heating up a little bit of concrete is inconsequential compared to all that water (see specific heat).

Those figures are way off on the benefits of insulation (< 35%, not 80%, even after other improvements). A pool cover that prevents evaporation is the primary saver. See here: http://noanderson.com/services/swimming-pool-energy-temperature-calculator/#

The object of the ICF is to maintain the water temperature in the pool without adverse effects from the surrounding ground. EPS on the outside is going to help keep that temperature stable out there and not draw it into the concrete allowing it to pass thru and into the water, the EPS on the water side is going to do the same. Based on the website you provided I should be paying $ 4,143.00 a year (actually 5 months) to heat my pool. I did have to use Rochester NY for a comparison as the closet city to me.

The object of the ICF is to maintain the water temperature in the pool without adverse effects from the surrounding ground.

Chris, 90% of the heat loss from an in-ground pool is out of the top, not through the sides. Someone is pulling someone's leg if you think that ICF can reduce a $1,000 operating cost to $200. This has been discussed before on this site if you want to search for it.

Yes most heat loss is thru the top, however, reflective heat from the ICF into the water reduces the amount of energy required to re-heat the water. It all works as part of the system

however, reflective heat from the ICF into the water reduces the amount of energy required to re-heat the water

Reflective heat? The point is that if you are losing 10% or less of the heat out the pool sides, you aren't going to cut your heat loss by 4/5 with anything you do there.

Your only looking at one piece of the puzzle. Look at the whole pool as a system not just one component. It is the same as house, ICF is only one part of the puzzle

Posted By ICFHybrid on 01 Jul 2013 09:04 AM

Chris, 90% of the heat loss from an in-ground pool is out of the top, not through the sides.

Ground temps are 48 and air temps above 60 24 hours a day and above 80 a part of the day. If you totally foam the water side and float a blanket on the air side I doubt 90% is to the air.

Posted By ICFHybrid on 01 Jul 2013 09:04 AM

The object of the ICF is to maintain the water temperature in the pool without adverse effects from the surrounding ground.

Chris, 90% of the heat loss from an in-ground pool is out of the top, not through the sides. Someone is pulling someone's leg if you think that ICF can reduce a $1,000 operating cost to $200. This has been discussed before on this site if you want to search for it.

I think that is why people use those cover things... Another piece of the puzzle....

I doubt 90% is to the air.

Are you aware of what happens, in terms of energy (heat), gain and loss when water evaporates?  When you "float a blanket", I presume you mean you are reducing that evaporation loss.

I just yesterday got my July/August edition of ICF Builder magazine which highlights ICF for swimming pools. The single edition can be had for $5 at their website. http://www.icfmag.com/order/index.php?main_page=index&cPath=16

Just a guess, but it might be hard to get an unbiased comparison of ICF vs poured wall+foam from anyone who sells ICFs.

It is tough when people are so passionate about ICF. But here is the deal. ICF is just plain and simple easier, it takes 3 steps of forming, insulating, and wrecking forms, down to just one step. FORMING. (with a little wrecking of braces). With the cost of ICF blocks getting lower and lumber getting higher, ICF is looking better all the time. This is coming from a guy who has done both, the only thing that ever makes me nervous about ICF is making sure the concrete is COMPLETELY consolidated within the forms. You must make sure your contractor is vibrating the heck out of the concrete. ICF is great, and formed wall + insulation is great too, but why not just simplify the process and do both of those things at once? that's my attempt at non biased take on ICF vs Formed wall + insulation. hope that helped.

Ryan,

I think the fear of a blowout makes some ICF installers so hesitant about vibrating concrete.  But without proper vibrating concrete in any type of wall, there can be no assurance that the wall is solid.  Too much air left in the concrete can lead to leaks.

Can't help but add my 2 cents to the vibrating conversation: Banging on the outside of the ICF wall with a 2x4 is not vibrating. Nor is running an orbital sander over the wall. Bashing a bladeless Sawzall on the wall is also not vibrating concrete. It's just banging on a wall. Use a normal concrete wall vibrator with a 1 inch head and do the job right. If your ICF will not stand up to that, use one that will.

It takes very little vibration to make a big difference if your mix is right. For me, one litre per meter of super plasticizer and a quick down and up of every other cell does the job. This amount of vibration with a 1" head will not cause a blowout on almost any of the forms on the market today.

If you have a blowout take the time to figure out why it happened and learn from it.

As I recall, the spec is something like 3 inches/second (quite slow) and < every 12" if you use a good 3/4 to 1" head vibrator. I suspect that very few people follow this.

http://amvic-pacific.com/Downloads/Tech%20Sheet%20-%20Vibrating%20Concrete.pdf

Posted By jonr on 03 Jul 2013 02:25 PM
As I recall, the spec is something like 3 inches/second (quite slow) and < every 12" if you use a good 3/4 to 1" head vibrator. I suspect that very few people follow this.

http://amvic-pacific.com/Downloads/Tech%20Sheet%20-%20Vibrating%20Concrete.pdf

From the referenced article
"High-powered vibrators and high slump concrete have larger fields of action"
Using super plasticizer raises the slump of the concrete without adding water allowing for a much larger sphere of influence from the vibrator head, which means you can move the vibrator faster and space it further apart with better results.