What are the best methods to insulate an ICF foundation in the North East below grade?

The common process for waterproofing an ICF wall is to use a waterproofing membrane directly on the ICF and then to apply a dimpled drain board over top to minimize hydrostatic pressure, ensure proper drainage and protect the waterproofing membrane.

Waterproofing membranes are available in peel & stick and liquid varieties. Be certain to use a water-based product that is certified to be compatible with expanded polystyrene (EPS). Solvent based products will dissolve the ICF and must not be used. Most waterproofing membranes will resist hydrostatic pressures up to 28psi – please consult the manufacturer’s specifications for individual products.

There are many peel & stick waterproofing membrane products that are compatible with ICF construction. However, water-based spray-on membranes seem to perform better because they are easier to install properly. The presence of small amounts of dew or moisture on the ICF wall can cause the peel & stick varieties to fail – not so for the spray-on types.

If you message me offline, I will provide names of specific products.

Very well put Bruce.

Posted By BrucePolycrete on 07 Mar 2012 07:37 PM
The common process for waterproofing an ICF wall is to use a waterproofing membrane directly on the ICF and then to apply a dimpled drain board over top to minimize hydrostatic pressure, ensure proper drainage and protect the waterproofing membrane.

Waterproofing membranes are available in peel & stick and liquid varieties. Be certain to use a water-based product that is certified to be compatible with expanded polystyrene (EPS). Solvent based products will dissolve the ICF and must not be used. Most waterproofing membranes will resist hydrostatic pressures up to 28psi – please consult the manufacturer’s specifications for individual products.

There are many peel & stick waterproofing membrane products that are compatible with ICF construction. However, water-based spray-on membranes seem to perform better because they are easier to install properly. The presence of small amounts of dew or moisture on the ICF wall can cause the peel & stick varieties to fail – not so for the spray-on types.

If you message me offline, I will provide names of specific products.

So what I read is that the dimple products are not much more effective than wall paneling and are just protection and not waterproofing. 

Am I interpreting your analysis to mean that neither a dimple product nor a peel & stick, nor a spray on are sufficient when used alone?

Logically it seems like the dimple product should shed water down to the weeping tile and then it drains away.  I don't get why hydrostatic pressure applies to water that should not be there to create any kind of pressure. 

For the product I use, I don't see a requirement for a double protection method.

(What would Alton's comment be on this?)

The waterproofing membrane prevents water infiltration, and the dimple drain board protects the membrane and permits the water to drain away. It's a two-part system.If you choose not to use the complete system, that's obviously your choice. You may not have hydrostatic pressure today, but what happens if conditions change? If you're only using the drain board, you will almost certainly have water infiltrating the ICF. In my view, you might as well do the job right the first time.

Posted By BrucePolycrete on 08 Mar 2012 01:11 AM
The waterproofing membrane prevents water infiltration, and the dimple drain board protects the membrane and permits the water to drain away. It's a two-part system.If you choose not to use the complete system, that's obviously your choice. You may not have hydrostatic pressure today, but what happens if conditions change? If you're only using the drain board, you will almost certainly have water infiltrating the ICF. In my view, you might as well do the job right the first time.

I don't think anybody would disagree with using redundant systems but my point is ... "is it necessary, or simply an added expense with little extra value?"  Why would the solid plastic dimple membrane not be a waterproofing material by itself?

I am still having a problem understanding why you would ever have hydrostatic pressure as long as you have a functioning weeping tile in place.  By the definition I read, hydrostatic pressure is created by a height of water.  Isn't the purpose of weeping tile to continuously drain water, thus what hydrostatic pressure scenario might you be suggesting?

It seems like your recommendation is treading on the "better" concept.  At some point don't redundant systems just become an expense with a diminishing return?  One could also put (as engineers like to specify in my area of expanding clay) granular fill as backfill.  Finding someone who actually does that is rare if it exists at all.

I would appreciate it if you would post a link to any ICF brand who specifies both dimple membrane and peel 'n stick (or spray membrane) in their installation instructions.

I'm always up for an education so please enlighten me as to what I am not understanding. 

At some point don't redundant systems just become an expense with a diminishing return?

Yes, they do, but does that mean you don't need them?

Peel and Sticks are not approved by code here!! Fortunately or unfortunately depending on how you view it most building departments are either not aware of this or don't enforce it.

We use peel and stick whenever we can, it is a product we know works, as well there are spray products that work equally as well. A protection board is used by us as most contractors (GC's) that we work for backfill with the onsite material that came out of the basement during the dig, this material 90% of the time is not acceptable as free draining materials. The use of protection board is just that, protection from large rocks and such that can and will puncture the peel and stick.

I only use dimpled membane and have never had a problem.  When I have a site with water problems I will first apply a liquid waterproofing under the dimpled but those are rare.  The advantage of dimple is it can be applied in all weather situations and even the day of the pour.  Tuesday it was 35 in upstate NY and we waterproofed 176 ft of 9'4" wall in a little over an hour for 3 men.  You can't beat the speed of the install and it cost less that peel n' stick.

You can't beat the speed of the install and it cost less that peel n' stick.

Did you apply horizontally or vertically and how did you seal the seams?

Posted By ICFHybrid on 08 Mar 2012 02:25 AM

At some point don't redundant systems just become an expense with a diminishing return?

Yes, they do, but does that mean you don't need them?

Is there not a technical difference between "need", "good idea", "can't hurt" ...... and "required"?  

If they are "needed", wouldn't they be spelled out in the building code since then they would be "required"?

One would think that the manufacturers would step up and make the double system a requirement for the proper functioning of their systems?

We already have a TV personality who is beating up on contractors by saying things like "a 2x6 is code but why not use a 2x12".  What is never revealed is the cost difference for the "premium" job.

Don't get me wrong here, I try to give my customers the best information and product that I can.  The wall we are up against is not what is best, it is who has the cheapest price.  

 

If they are "needed", wouldn't they be spelled out in the building code since then they would be "required"?

I would say that "need" is highly subjective. If you build to code minimum and your foundation leaks into your basement, then I guess you needed to have done something else.

The rolls are 65.5' long and the heights vary so you roll it out horizontally it's held in place by a 2" plastic washer that you screw into the web about every foot, with the taller dimpled you place a few in the field and corners.The lap joints are caulked with silicone. The only two things that can screw it up , are allowing dirt to fill the dimples when back filling and not putting stone on top of the footing before back filling. When I use it with my mono pour system we take a ice srapper and make grooves in the top of the footing on the outside. This allows the water to flow to the drain lines.

Let's be very careful when we talk about "building to code". "Code" is the lowest acceptable standard.If your kid gets a D in math, he passed. Do you encourage your kids to aspire to all D's? You can bet those homes in Joplin, MO and in Indiana and Kentucky that were annihilated by tornadoes were built to code.

My grandad and my uncle built houses since shortly after the turn of the last century, and one of their favorite sayings was, "It only costs a few cents more to overbuild and you get a much sturdier house." If you want to cheap out, cheap out. Me? I don't want to live in cheap surroundings.Why go to all the trouble of building a concrete home and cheap out on the waterproofing in order to avoid spending a few bucks? Makes no sense.

Funny thing happened during the recent spate of rain. My wife visited three homes for various functions during the same short period of time. All were newly built in the last three years and all were substantially in excess of a half million bucks. In all three homes there was a homeowner covered in mud trying to pump water out from under his home.

I think about how many times I would want to be doing that every five years or so and then I think about how much it would cost to waterproof and ...well, ....

The lap joints are caulked with silicone.

Do you find that the dimples mate up well on the overlaps? With the product I was using, it looked like the temperature of the plastic sheet had been allowed to vary too much during the production run, causing slight warping in places. Over about 6 feet, there was enough variation that the dimples stopped matching up so the seams couldn't be securely lapped.

Posted By BrucePolycrete on 08 Mar 2012 09:16 AM
Let's be very careful when we talk about "building to code". "Code" is the lowest acceptable standard.If your kid gets a D in math, he passed. Do you encourage your kids to aspire to all D's? You can bet those homes in Joplin, MO and in Indiana and Kentucky that were annihilated by tornadoes were built to code.

My grandad and my uncle built houses since shortly after the turn of the last century, and one of their favorite sayings was, "It only costs a few cents more to overbuild and you get a much sturdier house." If you want to cheap out, cheap out. Me? I don't want to live in cheap surroundings.Why go to all the trouble of building a concrete home and cheap out on the waterproofing in order to avoid spending a few bucks? Makes no sense.

I am not arguing against doing anything better than code.  I am also an inventor and scientist so I look for that technical break point where I tell my customer "this works, but if you want to pay more, then this double system is an insurance policy, and you may never know if it was actually necessary".  If I recommend a feature to my customer I would like it to be based in fact and not speculation.  Customers are already fed a bunch of hooey about ICF by people who should know better and I just don't want to be upcharging a job when it is not required. 

However, to extend this double waterproofing concept to other systems in a house would a person then use 2 layers of 6 mil poly instead of one as a vapor barrier, or R 120 in the attic instead of R60, and 12" thick exterior walls be "better"?

So far, what I am hearing is that either dimple membrane or peel 'n stick or spray by themselves is not sufficient. 

All-Sask. If that's your angle, why ask the question here? Check your local building code and there's your answer as to what's "required".

Posted By BrucePolycrete on 08 Mar 2012 09:16 AM
Let's be very careful when we talk about "building to code". "Code" is the lowest acceptable standard.

Your last post doesn't seem to jive with this one. 

I'm looking for facts, that's all.

Posted By BrucePolycrete on 08 Mar 2012 09:39 AM
All-Sask. If that's your angle, why ask the question here? Check your local building code and there's your answer as to what's "required".

Bruce, here's what really baffles me about this thread, and your comments. 

When I checked the PolyCrete installation manual (page 48) mentions a peel 'n stick only.   I was expecting to see dimple membrane over it.

It seems like this is a major flaw in what I am hearing in this thread.  What are your thoughts on your manual?